This is the large floor model with the radio and phono player.
The radio is playing very well.
I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
Thank you all for any help on this,
Mitch
First you have to determine from the schematic if this cell is unbiased i.e has no current running thru it from an external source i.e. radio.
There are three kinds of photocells to worry about.
1. CDS cell - resistive type needing bias
2. Tube type cell - also biased with HV
3. Photoelectric or battery type cell producing its own bias.
I would think that we have #3 here. If so , a radio shack sun battery cell that would fit into the old cells container should work. I have sent modulated light beams to these cells and connected them to an amplifier HI-Z input and they worked.
As for the original cell, take it out and put it in the sun - see if you get any volts with a DMM.
My 2 cents
Lou
:Hello everyone,
:
:This is the large floor model with the radio and phono player.
:
:The radio is playing very well.
:
:I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
:
:Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
:
:The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
:
:With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
:
:Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
:
:Thank you all for any help on this,
:
:Mitch
:
:
:
:
:This is the large floor model with the radio and phono player.
:
:The radio is playing very well.
:
:I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
:
:Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
:
:The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
:
:With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
:
:Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
:
:Thank you all for any help on this,
:
:Mitch
:
:
:
I suggest reading this thread on ARF:
Philco Beam of Light Photo Cell
It is quite informative and offers a suggestion for a replacement cell that is purported to work well.
Richard
Chuck has Philco information on his site:
http://philcorepairbench.com/phono.htm
Norm
::Hello everyone,
::
::This is the large floor model with the radio and phono player.
::
::The radio is playing very well.
::
::I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
::
::Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
::
::The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
::
::With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
::
::Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
::
::Thank you all for any help on this,
::
::Mitch
::
::
::
:
:I suggest reading this thread on ARF:
:
:Philco Beam of Light Photo Cell
:
:It is quite informative and offers a suggestion for a replacement cell that is purported to work well.
:
:Richard
:
:
: Chuck has Philco information on his site:
:
:http://philcorepairbench.com/phono.htm
:
:Norm
:
:::Hello everyone,
:::
:::This is the large floor model with the radio and phono player.
:::
:::The radio is playing very well.
:::
:::I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
:::
:::Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
:::
:::The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
:::
:::With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
:::
:::Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
:::
:::Thank you all for any help on this,
:::
:::Mitch
:::
:::
:::
::
::I suggest reading this thread on ARF:
::
::Philco Beam of Light Photo Cell
::
::It is quite informative and offers a suggestion for a replacement cell that is purported to work well.
::
::Richard
::
:
:
Hello to all,
The radio circuits for the tone arm are working, i was able to adjust the lamp to 3 volts. The stylus and mirror have been cleaned and there is no short fron the assenbly to the metal frame support.
It looks to me that the needle picks up the frequency of the record and transends it to the mirror which transmits it to the photocell. Then the signal goes through the small transformer (stepped up)and to the grid of the 7C6 (designator A).
I have found a new photoresistor (photocell) at Radio Shack that will fit in place of the old Photo Electric Cell.
This will only produce a change in resistance (light frequency) as the light from the mirror impacts it and should change the grid resistance.
Is this how this should work?
Also, I read somewhere that this was a photovoltaic cell, I do not think so because the first photovoltaic was not introduced until 1954.
All help and comments welcome.
Thank you,
Mitch
If you are NEW school trained, additionally, you should be able to dig up ANY one of your metal cased small signal transistor, like a 2N2905 in its larger TO-5 cases or a 2N2222 in its smaller TO-18 case. What you then do is cut off its top end, to open and then expose its internal semi wafer. Option two: The early worm DESERVES the bird. |
::Hi
::
:: Chuck has Philco information on his site:
::
::http://philcorepairbench.com/phono.htm
::
::Norm
::
::::Hello everyone,
::::
::::This is the large floor model with the radio and phono player.
::::
::::The radio is playing very well.
::::
::::I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
::::
::::Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
::::
::::The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
::::
::::With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
::::
::::Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
::::
::::Thank you all for any help on this,
::::
::::Mitch
::::
::::
::::
:::
:::I suggest reading this thread on ARF:
:::
:::Philco Beam of Light Photo Cell
:::
:::It is quite informative and offers a suggestion for a replacement cell that is purported to work well.
:::
:::Richard
:::
::
::
:Hello to all,
:
:The radio circuits for the tone arm are working, i was able to adjust the lamp to 3 volts. The stylus and mirror have been cleaned and there is no short fron the assenbly to the metal frame support.
:
:It looks to me that the needle picks up the frequency of the record and transends it to the mirror which transmits it to the photocell. Then the signal goes through the small transformer (stepped up)and to the grid of the 7C6 (designator A).
:
:I have found a new photoresistor (photocell) at Radio Shack that will fit in place of the old Photo Electric Cell.
:
:This will only produce a change in resistance (light frequency) as the light from the mirror impacts it and should change the grid resistance.
:
:Is this how this should work?
:
:Also, I read somewhere that this was a photovoltaic cell, I do not think so because the first photovoltaic was not introduced until 1954.
:
:All help and comments welcome.
:
:Thank you,
:
:Mitch
:
JUST FYI ALL
The first phtotvoltaic cell was created in 1883!!! ( According to Wikipedia).
I have seen them in many old devices and I have used them to receive music over a light beam. Seems like a good match to this project. Radio Shack has them.
Lou
:
:
:
:
:
:
:
:
:
:
:
:
:
:Sir Mitch . . . . .
:
:
:Methinks that you has done and wents and gots yourself the WRONGS type of deee-vice .
:Particularly if you confirm a serpentine path of its frontal element.
:
:
:Radical Shack offers a * * * * POT load of those cadmium sulfide . . .photo-RESISTIVE . . .e.g. variable resistance units.
:
:
:But with the only GENERATING units that I remember seeing in the past, were mamoth 2x2 in square Bee eyed (multiple frontal focusing lenses) modules that actually created many milliamperes of current output at a very low voltage.
:On a quick read of the test procedure where you put a voltmeter across the original Philco cell and expect
:a DEVELOPED output voltage level as per referencing below:
:
:
:
:
:
:
:
:
:
:PLUS that units design then mandates that the cells output is then expected to dump into a low impedance transformer primary for further stepping up..
:
:
:I can give you two experimentations to try.
:
:
:Option one:
:
:
:
:If you are NEW school trained, additionally, you should be able to dig up ANY one of your metal cased small signal transistor, like a 2N2905 in its larger TO-5 cases or a 2N2222 in its smaller TO-18 case.
:
:
:
:
:
:
:
:What you then do is cut off its top end, to open and then expose its internal semi wafer.
:
:
:Take DVM in hand and monitor between its base lead and then alternatively, have the other
:monitoring lead to either the collector or emitter to see which way gives the most voltage output.
:
:
:You are doing this while exposing the open top to a nearby table lamps light sourcing, so that you can vary the light level by distance positioning.
:
:
:If it puts out up to or ABOVE the expected meager voltages of the chart above, try using that for being your photocell.
:
:
:
:Option two:
:
:
:Is to try using the photocell bypassing the audio transformer.
:
:
:E.G . . .You would have your just bought photocell connected in to the 1st grid of that 7C6, but with one lead of the the transformer secondary DISCONNECTED.
:
:
:Initially try the other lead of the photocell going to ground, in that manner you can evaluate if that manner of photo resistive shifting the 1st grid bias of that circuit will provide enough voltage swing to create a high enough audio level.
:
:
:The other variance is to take that just mentioned lead, off ground and instead, feed a variable + low voltage to it to see if that varying + voltage swing working against the fixed self grid biasing created by the 7C6's cathode resistor.
:
:
:You would need to be using shielded wiring for the length of connections coming into that 7C6 1st grid.
:
:
:If that is working all right in that manner, it should surpass the frequency response limitations , by not having to pass through an audio transformer, as was being used.
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:73's de Edd
:
:
:
:
:
:
:The early worm DESERVES the bird.
:
:
:
:
:
:
:
:
:
:
:
:
:
:::Hi
:::
::: Chuck has Philco information on his site:
:::
:::http://philcorepairbench.com/phono.htm
:::
:::Norm
:::
:::::Hello everyone,
:::::
:::::This is the large floor model with the radio and phono player.
:::::
:::::The radio is playing very well.
:::::
:::::I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
:::::
:::::Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
:::::
:::::The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
:::::
:::::With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
:::::
:::::Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
:::::
:::::Thank you all for any help on this,
:::::
:::::Mitch
:::::
:::::
:::::
::::
::::I suggest reading this thread on ARF:
::::
::::Philco Beam of Light Photo Cell
::::
::::It is quite informative and offers a suggestion for a replacement cell that is purported to work well.
::::
::::Richard
::::
:::
:::
::Hello to all,
::
::The radio circuits for the tone arm are working, i was able to adjust the lamp to 3 volts. The stylus and mirror have been cleaned and there is no short fron the assenbly to the metal frame support.
::
::It looks to me that the needle picks up the frequency of the record and transends it to the mirror which transmits it to the photocell. Then the signal goes through the small transformer (stepped up)and to the grid of the 7C6 (designator A).
::
::I have found a new photoresistor (photocell) at Radio Shack that will fit in place of the old Photo Electric Cell.
::
::This will only produce a change in resistance (light frequency) as the light from the mirror impacts it and should change the grid resistance.
::
::Is this how this should work?
::
::Also, I read somewhere that this was a photovoltaic cell, I do not think so because the first photovoltaic was not introduced until 1954.
::
::All help and comments welcome.
::
::Thank you,
::
::Mitch
::
:
:
:
: : : : : : : : : : : :Sir Mitch . . . . . : : :Methinks that you has done and wents and gots yourself the WRONGS type of deee-vice . :Particularly if you confirm a serpentine path of its frontal element. : : :Radical Shack offers a * * * * POT load of those cadmium sulfide . . .photo-RESISTIVE . . .e.g. variable resistance units. : : :But with the only GENERATING units that I remember seeing in the past, were mamoth 2x2 in square Bee eyed (multiple frontal focusing lenses) modules that actually created many milliamperes of current output at a very low voltage. :On a quick read of the test procedure where you put a voltmeter across the original Philco cell and expect :a DEVELOPED output voltage level as per referencing below: : : : : : : : : : :PLUS that units design then mandates that the cells output is then expected to dump into a low impedance transformer primary for further stepping up.. : : :I can give you two experimentations to try. : : :Option one: : : : :If you are NEW school trained, additionally, you should be able to dig up ANY one of your metal cased small signal transistor, like a 2N2905 in its larger TO-5 cases or a 2N2222 in its smaller TO-18 case. : : : : : : : :What you then do is cut off its top end, to open and then expose its internal semi wafer. : : :Take DVM in hand and monitor between its base lead and then alternatively, have the other :monitoring lead to either the collector or emitter to see which way gives the most voltage output. : : :You are doing this while exposing the open top to a nearby table lamps light sourcing, so that you can vary the light level by distance positioning. : : :If it puts out up to or ABOVE the expected meager voltages of the chart above, try using that for being your photocell. : : : :Option two: : : :Is to try using the photocell bypassing the audio transformer. : : :E.G . . .You would have your just bought photocell connected in to the 1st grid of that 7C6, but with one lead of the the transformer secondary DISCONNECTED. : : :Initially try the other lead of the photocell going to ground, in that manner you can evaluate if that manner of photo resistive shifting the 1st grid bias of that circuit will provide enough voltage swing to create a high enough audio level. : : :The other variance is to take that just mentioned lead, off ground and instead, feed a variable + low voltage to it to see if that varying + voltage swing working against the fixed self grid biasing created by the 7C6's cathode resistor. : : :You would need to be using shielded wiring for the length of connections coming into that 7C6 1st grid. : : :If that is working all right in that manner, it should surpass the frequency response limitations , by not having to pass through an audio transformer, as was being used. : : : : : : : : : : : : : : :73's de Edd : : : : : : :The early worm DESERVES the bird. : : : : : : : : : |
:
:
:
:
:::Hi
:::
::: Chuck has Philco information on his site:
:::
:::http://philcorepairbench.com/phono.htm
:::
:::Norm
:::
:::::Hello everyone,
:::::
:::::This is the large floor model with the radio and phono player.
:::::
:::::The radio is playing very well.
:::::
:::::I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
:::::
:::::Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
:::::
:::::The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
:::::
:::::With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
:::::
:::::Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
:::::
:::::Thank you all for any help on this,
:::::
:::::Mitch
:::::
:::::
:::::
::::
::::I suggest reading this thread on ARF:
::::
::::Philco Beam of Light Photo Cell
::::
::::It is quite informative and offers a suggestion for a replacement cell that is purported to work well.
::::
::::Richard
::::
:::
:::
::Hello to all,
::
::The radio circuits for the tone arm are working, i was able to adjust the lamp to 3 volts. The stylus and mirror have been cleaned and there is no short fron the assenbly to the metal frame support.
::
::It looks to me that the needle picks up the frequency of the record and transends it to the mirror which transmits it to the photocell. Then the signal goes through the small transformer (stepped up)and to the grid of the 7C6 (designator A).
::
::I have found a new photoresistor (photocell) at Radio Shack that will fit in place of the old Photo Electric Cell.
::
::This will only produce a change in resistance (light frequency) as the light from the mirror impacts it and should change the grid resistance.
::
::Is this how this should work?
::
::Also, I read somewhere that this was a photovoltaic cell, I do not think so because the first photovoltaic was not introduced until 1954.
::
::All help and comments welcome.
::
::Thank you,
::
::Mitch
::
:
:
All of the readers on this post need only to see Edd's graph.
I know I need at least 40 mili volts.
Thank you again Edd, I will keep the post to success.
Mitch
FIO . . .the use of emitter to base is not as productive in output. Give the PRIMARY DC resistance readings on the BLUE -BROWN wires and then the SECONDARY winding that is probably the easiest accessible by measuring between the 1st grid of the 7C6 and ground.
|
::
::
::
::
::
::
::
::
::
::
::
::
::
::Sir Mitch . . . . .
::
::
::Methinks that you has done and wents and gots yourself the WRONGS type of deee-vice .
::Particularly if you confirm a serpentine path of its frontal element.
::
::
::Radical Shack offers a * * * * POT load of those cadmium sulfide . . .photo-RESISTIVE . . .e.g. variable resistance units.
::
::
::But with the only GENERATING units that I remember seeing in the past, were mamoth 2x2 in square Bee eyed (multiple frontal focusing lenses) modules that actually created many milliamperes of current output at a very low voltage.
::On a quick read of the test procedure where you put a voltmeter across the original Philco cell and expect
::a DEVELOPED output voltage level as per referencing below:
::
::
::
::
::
::
::
::
::
::PLUS that units design then mandates that the cells output is then expected to dump into a low impedance transformer primary for further stepping up..
::
::
::I can give you two experimentations to try.
::
::
::Option one:
::
::
::
::If you are NEW school trained, additionally, you should be able to dig up ANY one of your metal cased small signal transistor, like a 2N2905 in its larger TO-5 cases or a 2N2222 in its smaller TO-18 case.
::
::
::
::
::
::
::
::What you then do is cut off its top end, to open and then expose its internal semi wafer.
::
::
::Take DVM in hand and monitor between its base lead and then alternatively, have the other
::monitoring lead to either the collector or emitter to see which way gives the most voltage output.
::
::
::You are doing this while exposing the open top to a nearby table lamps light sourcing, so that you can vary the light level by distance positioning.
::
::
::If it puts out up to or ABOVE the expected meager voltages of the chart above, try using that for being your photocell.
::
::
::
::Option two:
::
::
::Is to try using the photocell bypassing the audio transformer.
::
::
::E.G . . .You would have your just bought photocell connected in to the 1st grid of that 7C6, but with one lead of the the transformer secondary DISCONNECTED.
::
::
::Initially try the other lead of the photocell going to ground, in that manner you can evaluate if that manner of photo resistive shifting the 1st grid bias of that circuit will provide enough voltage swing to create a high enough audio level.
::
::
::The other variance is to take that just mentioned lead, off ground and instead, feed a variable + low voltage to it to see if that varying + voltage swing working against the fixed self grid biasing created by the 7C6's cathode resistor.
::
::
::You would need to be using shielded wiring for the length of connections coming into that 7C6 1st grid.
::
::
::If that is working all right in that manner, it should surpass the frequency response limitations , by not having to pass through an audio transformer, as was being used.
::
::
::
::
::
::
::
::
::
::
::
::
::
::
::73's de Edd
::
::
::
::
::
::
::The early worm DESERVES the bird.
::
::
::
::
::
::
::
::
::
::
::
::
::
::::Hi
::::
:::: Chuck has Philco information on his site:
::::
::::http://philcorepairbench.com/phono.htm
::::
::::Norm
::::
::::::Hello everyone,
::::::
::::::This is the large floor model with the radio and phono player.
::::::
::::::The radio is playing very well.
::::::
::::::I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
::::::
::::::Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
::::::
::::::The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
::::::
::::::With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
::::::
::::::Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
::::::
::::::Thank you all for any help on this,
::::::
::::::Mitch
::::::
::::::
::::::
:::::
:::::I suggest reading this thread on ARF:
:::::
:::::Philco Beam of Light Photo Cell
:::::
:::::It is quite informative and offers a suggestion for a replacement cell that is purported to work well.
:::::
:::::Richard
:::::
::::
::::
:::Hello to all,
:::
:::The radio circuits for the tone arm are working, i was able to adjust the lamp to 3 volts. The stylus and mirror have been cleaned and there is no short fron the assenbly to the metal frame support.
:::
:::It looks to me that the needle picks up the frequency of the record and transends it to the mirror which transmits it to the photocell. Then the signal goes through the small transformer (stepped up)and to the grid of the 7C6 (designator A).
:::
:::I have found a new photoresistor (photocell) at Radio Shack that will fit in place of the old Photo Electric Cell.
:::
:::This will only produce a change in resistance (light frequency) as the light from the mirror impacts it and should change the grid resistance.
:::
:::Is this how this should work?
:::
:::Also, I read somewhere that this was a photovoltaic cell, I do not think so because the first photovoltaic was not introduced until 1954.
:::
:::All help and comments welcome.
:::
:::Thank you,
:::
:::Mitch
:::
::
::
:All of the readers on this post need only to see Edd's graph.
:
:I know I need at least 40 mili volts.
:
:Thank you again Edd, I will keep the post to success.
:
:Mitch
:
:
:
: : : : : : :Edd was here . . . . : : : : : : : :Sir Mitch. . . . . : : :I was at a site where I couldn’t make any more finely detailed confirmations while composing that last info that I gave you, specifically the utilization of a silicon transistor for its PHOTOVOLTAIC generating capabilities. : : :We know well, its additional photo RESISTIVE capabilities. : : :AND it seems that only you and I are understanding the absolute necessity aspect of there being a photovoltaic “voltage” GENERATING and that’s being HEAVY ON the GENERATING aspect. : : :Now upon opening the top TO-18 case of inventory item count # 765 of my 2N2222's, I lost the first one due to the high speed resonations of a Dremel driven cut off wheel. Both beam leads popped off from their ball beam bonds. :A slower speed bench grinder got the second attempted unit open, and WOW is that semi die SMALL . . . . time had let me forget. :I am now confirming that the transistors base connection is being the POSITIVE polarity of your generated voltage with the collector being the NEGATIVE connection. : :FIO . . .the use of emitter to base is not as productive in output. : : :With the incoming photons having to line up at dress left dress in order to hit the small silicon semi die and getting out only ~ 60MV with BRIGHT light, time to try new things, figuring that the big brother PNP 2N2905 should only justify a 4 times larger die . . . it then being a full fly speck size ! : : :I found a bag of TO-66 power units and popped one of their tops and found a HEFTY size die being used, as per the illustration below: : : : : :  : : :Figuring that I needed some degree of load on that voltage output I utilized my Triplett 630 NA for presenting any analytical measurements. : : :Initially I clicked to voltage measurement and read 450 millivolts and that is with the loading down factor of 6,000 ohms by the meter in that scale used. : : :Next, in the clicking to current mode, so that the developed voltage output is then dumping into a current range multiplier short of 200 ohms, I am then reading .4 milliamperes. : : :So this unit is now having such a spread out, potential photon bombardment area on its die, such that some power is now being generated. : : :with this larger unit. But not to large, as your photo of the light beam “slot” landing on the photocells old yallered cover seems to be of about the right width. : : :That being with it initially aligned 1/2 off the photocell and swing over to covering more of it on bass / volume excursions of the groove deflecting the mirror. :The 2222 was giving a minimal 60MV while the new candidate is outputting 450 Millivolts max or even ~ 100mv a foot away from the light source. : : :I’m ‘bout ready to take this prepared unit and mail it to you but I would like you to make two resistance readings for me in relation to that transformer that the photocell dumps into. : : Give the PRIMARY DC resistance readings on the BLUE -BROWN wires and then the SECONDARY winding that is probably the easiest accessible by measuring between the 1st grid of the 7C6 and ground. : : :And BTW if anyone else had looked at the units schema, they would see the PHOTOVOLTAIC cell connecting right directly into a primary of a transformer. As it is designed, there is no source of voltage for a PHOTORESISTIVE cell to series conduct with. : : :Waiting for the resistances so that I can “ load “ down the cell in the same manner . . . and see how it outputs . : : : : : : : : :73's de Edd : : : : : :The first testicular guard, the "Cup," was used in Hockey in 1874 and the first helmet was used in 1974. :Now, that means it ONLY took 100 years for men to realize that their brain is ALSO important. : : : : : : : : : |
:
:
:
:
:
:
:::
:::
::: ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: :::Sir Mitch . . . . . ::: ::: :::Methinks that you has done and wents and gots yourself the WRONGS type of deee-vice . :::Particularly if you confirm a serpentine path of its frontal element. ::: ::: :::Radical Shack offers a * * * * POT load of those cadmium sulfide . . .photo-RESISTIVE . . .e.g. variable resistance units. ::: ::: :::But with the only GENERATING units that I remember seeing in the past, were mamoth 2x2 in square Bee eyed (multiple frontal focusing lenses) modules that actually created many milliamperes of current output at a very low voltage. :::On a quick read of the test procedure where you put a voltmeter across the original Philco cell and expect :::a DEVELOPED output voltage level as per referencing below: ::: ::: ::: ::: ::: ::: ::: ::: ::: :::PLUS that units design then mandates that the cells output is then expected to dump into a low impedance transformer primary for further stepping up.. ::: ::: :::I can give you two experimentations to try. ::: ::: :::Option one: ::: ::: ::: :::If you are NEW school trained, additionally, you should be able to dig up ANY one of your metal cased small signal transistor, like a 2N2905 in its larger TO-5 cases or a 2N2222 in its smaller TO-18 case. ::: ::: ::: ::: ::: ::: ::: :::What you then do is cut off its top end, to open and then expose its internal semi wafer. ::: ::: :::Take DVM in hand and monitor between its base lead and then alternatively, have the other :::monitoring lead to either the collector or emitter to see which way gives the most voltage output. ::: ::: :::You are doing this while exposing the open top to a nearby table lamps light sourcing, so that you can vary the light level by distance positioning. ::: ::: :::If it puts out up to or ABOVE the expected meager voltages of the chart above, try using that for being your photocell. ::: ::: ::: :::Option two: ::: ::: :::Is to try using the photocell bypassing the audio transformer. ::: ::: :::E.G . . .You would have your just bought photocell connected in to the 1st grid of that 7C6, but with one lead of the the transformer secondary DISCONNECTED. ::: ::: :::Initially try the other lead of the photocell going to ground, in that manner you can evaluate if that manner of photo resistive shifting the 1st grid bias of that circuit will provide enough voltage swing to create a high enough audio level. ::: ::: :::The other variance is to take that just mentioned lead, off ground and instead, feed a variable + low voltage to it to see if that varying + voltage swing working against the fixed self grid biasing created by the 7C6's cathode resistor. ::: ::: :::You would need to be using shielded wiring for the length of connections coming into that 7C6 1st grid. ::: ::: :::If that is working all right in that manner, it should surpass the frequency response limitations , by not having to pass through an audio transformer, as was being used. ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: :::73's de Edd ::: ::: ::: ::: ::: ::: :::The early worm DESERVES the bird. ::: ::: ::: ::: ::: ::: ::: ::: ::: |
:::
:::
:::
:::
:::::Hi
:::::
::::: Chuck has Philco information on his site:
:::::
:::::http://philcorepairbench.com/phono.htm
:::::
:::::Norm
:::::
:::::::Hello everyone,
:::::::
:::::::This is the large floor model with the radio and phono player.
:::::::
:::::::The radio is playing very well.
:::::::
:::::::I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
:::::::
:::::::Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
:::::::
:::::::The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
:::::::
:::::::With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
:::::::
:::::::Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
:::::::
:::::::Thank you all for any help on this,
:::::::
:::::::Mitch
:::::::
:::::::
:::::::
::::::
::::::I suggest reading this thread on ARF:
::::::
::::::Philco Beam of Light Photo Cell
::::::
::::::It is quite informative and offers a suggestion for a replacement cell that is purported to work well.
::::::
::::::Richard
::::::
:::::
:::::
::::Hello to all,
::::
::::The radio circuits for the tone arm are working, i was able to adjust the lamp to 3 volts. The stylus and mirror have been cleaned and there is no short fron the assenbly to the metal frame support.
::::
::::It looks to me that the needle picks up the frequency of the record and transends it to the mirror which transmits it to the photocell. Then the signal goes through the small transformer (stepped up)and to the grid of the 7C6 (designator A).
::::
::::I have found a new photoresistor (photocell) at Radio Shack that will fit in place of the old Photo Electric Cell.
::::
::::This will only produce a change in resistance (light frequency) as the light from the mirror impacts it and should change the grid resistance.
::::
::::Is this how this should work?
::::
::::Also, I read somewhere that this was a photovoltaic cell, I do not think so because the first photovoltaic was not introduced until 1954.
::::
::::All help and comments welcome.
::::
::::Thank you,
::::
::::Mitch
::::
:::
:::
::All of the readers on this post need only to see Edd's graph.
::
::I know I need at least 40 mili volts.
::
::Thank you again Edd, I will keep the post to success.
::
::Mitch
::
:
:
Hello Edd and all,
The primary is 108 ohms and the secondary is 1.6K ohms. The transformer is mounted between the radio and the phono so it was easy to measure.
I am sending you an email with my address, i should have it from the past.
I appreciate the help on this.
Mitch
::
::
:: :: :: :: :: :: ::Edd was here . . . . :: :: :: :: :: :: :: ::Sir Mitch. . . . . :: :: ::I was at a site where I couldn’t make any more finely detailed confirmations while composing that last info that I gave you, specifically the utilization of a silicon transistor for its PHOTOVOLTAIC generating capabilities. :: :: ::We know well, its additional photo RESISTIVE capabilities. :: :: ::AND it seems that only you and I are understanding the absolute necessity aspect of there being a photovoltaic “voltage” GENERATING and that’s being HEAVY ON the GENERATING aspect. :: :: ::Now upon opening the top TO-18 case of inventory item count # 765 of my 2N2222's, I lost the first one due to the high speed resonations of a Dremel driven cut off wheel. Both beam leads popped off from their ball beam bonds. ::A slower speed bench grinder got the second attempted unit open, and WOW is that semi die SMALL . . . . time had let me forget. ::I am now confirming that the transistors base connection is being the POSITIVE polarity of your generated voltage with the collector being the NEGATIVE connection. :: ::FIO . . .the use of emitter to base is not as productive in output. :: :: ::With the incoming photons having to line up at dress left dress in order to hit the small silicon semi die and getting out only ~ 60MV with BRIGHT light, time to try new things, figuring that the big brother PNP 2N2905 should only justify a 4 times larger die . . . it then being a full fly speck size ! :: :: ::I found a bag of TO-66 power units and popped one of their tops and found a HEFTY size die being used, as per the illustration below: :: :: :: :: :: :: :: ::Figuring that I needed some degree of load on that voltage output I utilized my Triplett 630 NA for presenting any analytical measurements. :: :: ::Initially I clicked to voltage measurement and read 450 millivolts and that is with the loading down factor of 6,000 ohms by the meter in that scale used. :: :: ::Next, in the clicking to current mode, so that the developed voltage output is then dumping into a current range multiplier short of 200 ohms, I am then reading .4 milliamperes. :: :: ::So this unit is now having such a spread out, potential photon bombardment area on its die, such that some power is now being generated. :: :: ::with this larger unit. But not to large, as your photo of the light beam “slot” landing on the photocells old yallered cover seems to be of about the right width. :: :: ::That being with it initially aligned 1/2 off the photocell and swing over to covering more of it on bass / volume excursions of the groove deflecting the mirror. ::The 2222 was giving a minimal 60MV while the new candidate is outputting 450 Millivolts max or even ~ 100mv a foot away from the light source. :: :: ::I’m ‘bout ready to take this prepared unit and mail it to you but I would like you to make two resistance readings for me in relation to that transformer that the photocell dumps into. :: :: Give the PRIMARY DC resistance readings on the BLUE -BROWN wires and then the SECONDARY winding that is probably the easiest accessible by measuring between the 1st grid of the 7C6 and ground. :: :: ::And BTW if anyone else had looked at the units schema, they would see the PHOTOVOLTAIC cell connecting right directly into a primary of a transformer. As it is designed, there is no source of voltage for a PHOTORESISTIVE cell to series conduct with. :: :: ::Waiting for the resistances so that I can “ load “ down the cell in the same manner . . . and see how it outputs . :: :: :: :: :: :: :: :: ::73's de Edd :: :: :: :: :: ::The first testicular guard, the "Cup," was used in Hockey in 1874 and the first helmet was used in 1974. ::Now, that means it ONLY took 100 years for men to realize that their brain is ALSO important. :: :: :: :: :: :: :: :: :: |
::
::
::
::
::
::
::::
::::
:::: :::: :::: :::: :::: :::: :::: :::: :::: :::: :::: ::::Sir Mitch . . . . . :::: :::: ::::Methinks that you has done and wents and gots yourself the WRONGS type of deee-vice . ::::Particularly if you confirm a serpentine path of its frontal element. :::: :::: ::::Radical Shack offers a * * * * POT load of those cadmium sulfide . . .photo-RESISTIVE . . .e.g. variable resistance units. :::: :::: ::::But with the only GENERATING units that I remember seeing in the past, were mamoth 2x2 in square Bee eyed (multiple frontal focusing lenses) modules that actually created many milliamperes of current output at a very low voltage. ::::On a quick read of the test procedure where you put a voltmeter across the original Philco cell and expect ::::a DEVELOPED output voltage level as per referencing below: :::: :::: :::: :::: :::: :::: :::: :::: :::: ::::PLUS that units design then mandates that the cells output is then expected to dump into a low impedance transformer primary for further stepping up.. :::: :::: ::::I can give you two experimentations to try. :::: :::: ::::Option one: :::: :::: :::: ::::If you are NEW school trained, additionally, you should be able to dig up ANY one of your metal cased small signal transistor, like a 2N2905 in its larger TO-5 cases or a 2N2222 in its smaller TO-18 case. :::: :::: :::: :::: :::: :::: :::: ::::What you then do is cut off its top end, to open and then expose its internal semi wafer. :::: :::: ::::Take DVM in hand and monitor between its base lead and then alternatively, have the other ::::monitoring lead to either the collector or emitter to see which way gives the most voltage output. :::: :::: ::::You are doing this while exposing the open top to a nearby table lamps light sourcing, so that you can vary the light level by distance positioning. :::: :::: ::::If it puts out up to or ABOVE the expected meager voltages of the chart above, try using that for being your photocell. :::: :::: :::: ::::Option two: :::: :::: ::::Is to try using the photocell bypassing the audio transformer. :::: :::: ::::E.G . . .You would have your just bought photocell connected in to the 1st grid of that 7C6, but with one lead of the the transformer secondary DISCONNECTED. :::: :::: ::::Initially try the other lead of the photocell going to ground, in that manner you can evaluate if that manner of photo resistive shifting the 1st grid bias of that circuit will provide enough voltage swing to create a high enough audio level. :::: :::: ::::The other variance is to take that just mentioned lead, off ground and instead, feed a variable + low voltage to it to see if that varying + voltage swing working against the fixed self grid biasing created by the 7C6's cathode resistor. :::: :::: ::::You would need to be using shielded wiring for the length of connections coming into that 7C6 1st grid. :::: :::: ::::If that is working all right in that manner, it should surpass the frequency response limitations , by not having to pass through an audio transformer, as was being used. :::: :::: :::: :::: :::: :::: :::: :::: :::: :::: :::: :::: :::: :::: ::::73's de Edd :::: :::: :::: :::: :::: :::: ::::The early worm DESERVES the bird. :::: :::: :::: :::: :::: :::: :::: :::: :::: |
::::
::::
::::
::::
::::::Hi
::::::
:::::: Chuck has Philco information on his site:
::::::
::::::http://philcorepairbench.com/phono.htm
::::::
::::::Norm
::::::
::::::::Hello everyone,
::::::::
::::::::This is the large floor model with the radio and phono player.
::::::::
::::::::The radio is playing very well.
::::::::
::::::::I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
::::::::
::::::::Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
::::::::
::::::::The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
::::::::
::::::::With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
::::::::
::::::::Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
::::::::
::::::::Thank you all for any help on this,
::::::::
::::::::Mitch
::::::::
::::::::
::::::::
:::::::
:::::::I suggest reading this thread on ARF:
:::::::
:::::::Philco Beam of Light Photo Cell
:::::::
:::::::It is quite informative and offers a suggestion for a replacement cell that is purported to work well.
:::::::
:::::::Richard
:::::::
::::::
::::::
:::::Hello to all,
:::::
:::::The radio circuits for the tone arm are working, i was able to adjust the lamp to 3 volts. The stylus and mirror have been cleaned and there is no short fron the assenbly to the metal frame support.
:::::
:::::It looks to me that the needle picks up the frequency of the record and transends it to the mirror which transmits it to the photocell. Then the signal goes through the small transformer (stepped up)and to the grid of the 7C6 (designator A).
:::::
:::::I have found a new photoresistor (photocell) at Radio Shack that will fit in place of the old Photo Electric Cell.
:::::
:::::This will only produce a change in resistance (light frequency) as the light from the mirror impacts it and should change the grid resistance.
:::::
:::::Is this how this should work?
:::::
:::::Also, I read somewhere that this was a photovoltaic cell, I do not think so because the first photovoltaic was not introduced until 1954.
:::::
:::::All help and comments welcome.
:::::
:::::Thank you,
:::::
:::::Mitch
:::::
::::
::::
:::All of the readers on this post need only to see Edd's graph.
:::
:::I know I need at least 40 mili volts.
:::
:::Thank you again Edd, I will keep the post to success.
:::
:::Mitch
:::
::
::
:Hello Edd and all,
:
:The primary is 108 ohms and the secondary is 1.6K ohms. The transformer is mounted between the radio and the phono so it was easy to measure.
:
:I am sending you an email with my address, i should have it from the past.
:
:I appreciate the help on this.
:
:Mitch
:
:
:
I recently rebuilt my tone arm with a "replacement" photo cell and I do have replacement bulbs that work also. I have 2 rebuilt complete tone arms if you are interested in purchasing. I have my 41-608 working perfectly after rebuilding.
:
:
: : : : : : :Edd was here . . . . : : : : : : : :Sir Mitch. . . . . : : :I was at a site where I couldn’t make any more finely detailed confirmations while composing that last info that I gave you, specifically the utilization of a silicon transistor for its PHOTOVOLTAIC generating capabilities. : : :We know well, its additional photo RESISTIVE capabilities. : : :AND it seems that only you and I are understanding the absolute necessity aspect of there being a photovoltaic “voltage” GENERATING and that’s being HEAVY ON the GENERATING aspect. : : :Now upon opening the top TO-18 case of inventory item count # 765 of my 2N2222's, I lost the first one due to the high speed resonations of a Dremel driven cut off wheel. Both beam leads popped off from their ball beam bonds. :A slower speed bench grinder got the second attempted unit open, and WOW is that semi die SMALL . . . . time had let me forget. :I am now confirming that the transistors base connection is being the POSITIVE polarity of your generated voltage with the collector being the NEGATIVE connection. : :FIO . . .the use of emitter to base is not as productive in output. : : :With the incoming photons having to line up at dress left dress in order to hit the small silicon semi die and getting out only ~ 60MV with BRIGHT light, time to try new things, figuring that the big brother PNP 2N2905 should only justify a 4 times larger die . . . it then being a full fly speck size ! : : :I found a bag of TO-66 power units and popped one of their tops and found a HEFTY size die being used, as per the illustration below: : : : : : : : :Figuring that I needed some degree of load on that voltage output I utilized my Triplett 630 NA for presenting any analytical measurements. : : :Initially I clicked to voltage measurement and read 450 millivolts and that is with the loading down factor of 6,000 ohms by the meter in that scale used. : : :Next, in the clicking to current mode, so that the developed voltage output is then dumping into a current range multiplier short of 200 ohms, I am then reading .4 milliamperes. : : :So this unit is now having such a spread out, potential photon bombardment area on its die, such that some power is now being generated. : : :with this larger unit. But not to large, as your photo of the light beam “slot” landing on the photocells old yallered cover seems to be of about the right width. : : :That being with it initially aligned 1/2 off the photocell and swing over to covering more of it on bass / volume excursions of the groove deflecting the mirror. :The 2222 was giving a minimal 60MV while the new candidate is outputting 450 Millivolts max or even ~ 100mv a foot away from the light source. : : :I’m ‘bout ready to take this prepared unit and mail it to you but I would like you to make two resistance readings for me in relation to that transformer that the photocell dumps into. : : Give the PRIMARY DC resistance readings on the BLUE -BROWN wires and then the SECONDARY winding that is probably the easiest accessible by measuring between the 1st grid of the 7C6 and ground. : : :And BTW if anyone else had looked at the units schema, they would see the PHOTOVOLTAIC cell connecting right directly into a primary of a transformer. As it is designed, there is no source of voltage for a PHOTORESISTIVE cell to series conduct with. : : :Waiting for the resistances so that I can “ load “ down the cell in the same manner . . . and see how it outputs . : : : : : : : : :73's de Edd : : : : : :The first testicular guard, the "Cup," was used in Hockey in 1874 and the first helmet was used in 1974. :Now, that means it ONLY took 100 years for men to realize that their brain is ALSO important. : : : : : : : : : |
:
:
:
:
:
:
:::
:::
::: ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: :::Sir Mitch . . . . . ::: ::: :::Methinks that you has done and wents and gots yourself the WRONGS type of deee-vice . :::Particularly if you confirm a serpentine path of its frontal element. ::: ::: :::Radical Shack offers a * * * * POT load of those cadmium sulfide . . .photo-RESISTIVE . . .e.g. variable resistance units. ::: ::: :::But with the only GENERATING units that I remember seeing in the past, were mamoth 2x2 in square Bee eyed (multiple frontal focusing lenses) modules that actually created many milliamperes of current output at a very low voltage. :::On a quick read of the test procedure where you put a voltmeter across the original Philco cell and expect :::a DEVELOPED output voltage level as per referencing below: ::: ::: ::: ::: ::: ::: ::: ::: ::: :::PLUS that units design then mandates that the cells output is then expected to dump into a low impedance transformer primary for further stepping up.. ::: ::: :::I can give you two experimentations to try. ::: ::: :::Option one: ::: ::: ::: :::If you are NEW school trained, additionally, you should be able to dig up ANY one of your metal cased small signal transistor, like a 2N2905 in its larger TO-5 cases or a 2N2222 in its smaller TO-18 case. ::: ::: ::: ::: ::: ::: ::: :::What you then do is cut off its top end, to open and then expose its internal semi wafer. ::: ::: :::Take DVM in hand and monitor between its base lead and then alternatively, have the other :::monitoring lead to either the collector or emitter to see which way gives the most voltage output. ::: ::: :::You are doing this while exposing the open top to a nearby table lamps light sourcing, so that you can vary the light level by distance positioning. ::: ::: :::If it puts out up to or ABOVE the expected meager voltages of the chart above, try using that for being your photocell. ::: ::: ::: :::Option two: ::: ::: :::Is to try using the photocell bypassing the audio transformer. ::: ::: :::E.G . . .You would have your just bought photocell connected in to the 1st grid of that 7C6, but with one lead of the the transformer secondary DISCONNECTED. ::: ::: :::Initially try the other lead of the photocell going to ground, in that manner you can evaluate if that manner of photo resistive shifting the 1st grid bias of that circuit will provide enough voltage swing to create a high enough audio level. ::: ::: :::The other variance is to take that just mentioned lead, off ground and instead, feed a variable + low voltage to it to see if that varying + voltage swing working against the fixed self grid biasing created by the 7C6's cathode resistor. ::: ::: :::You would need to be using shielded wiring for the length of connections coming into that 7C6 1st grid. ::: ::: :::If that is working all right in that manner, it should surpass the frequency response limitations , by not having to pass through an audio transformer, as was being used. ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: ::: :::73's de Edd ::: ::: ::: ::: ::: ::: :::The early worm DESERVES the bird. ::: ::: ::: ::: ::: ::: ::: ::: ::: |
:::
:::
:::
:::
:::::Hi
:::::
::::: Chuck has Philco information on his site:
:::::
:::::http://philcorepairbench.com/phono.htm
:::::
:::::Norm
:::::
:::::::Hello everyone,
:::::::
:::::::This is the large floor model with the radio and phono player.
:::::::
:::::::The radio is playing very well.
:::::::
:::::::I am now working to restore the phono. The attached photo shows the tone arm assembly of the beam of light detector for the pick up of the record.
:::::::
:::::::Notice that the lamp #97 is lit, this is the beam that strikes the mirror of the pick up assembly. This then directs the light beam to the electric photo cell. Pretty simple,so it seems.
:::::::
:::::::The light as you can see from the photo is striking the photo cell, when i touch the needle of the pick up mirror there is no speaker response. If i shine a bright light into the photo cell ther is still no response from the speaker.
:::::::
:::::::With any light on the photo cell there is a 0.0 volt measurement. I think that the photo cell is bad.
:::::::
:::::::Now i need advice as to what to replace it with or any other tests i can make to determine if it is really bad?
:::::::
:::::::Thank you all for any help on this,
:::::::
:::::::Mitch
:::::::
:::::::
:::::::
::::::
::::::I suggest reading this thread on ARF:
::::::
::::::Philco Beam of Light Photo Cell
::::::
::::::It is quite informative and offers a suggestion for a replacement cell that is purported to work well.
::::::
::::::Richard
::::::
:::::
:::::
::::Hello to all,
::::
::::The radio circuits for the tone arm are working, i was able to adjust the lamp to 3 volts. The stylus and mirror have been cleaned and there is no short fron the assenbly to the metal frame support.
::::
::::It looks to me that the needle picks up the frequency of the record and transends it to the mirror which transmits it to the photocell. Then the signal goes through the small transformer (stepped up)and to the grid of the 7C6 (designator A).
::::
::::I have found a new photoresistor (photocell) at Radio Shack that will fit in place of the old Photo Electric Cell.
::::
::::This will only produce a change in resistance (light frequency) as the light from the mirror impacts it and should change the grid resistance.
::::
::::Is this how this should work?
::::
::::Also, I read somewhere that this was a photovoltaic cell, I do not think so because the first photovoltaic was not introduced until 1954.
::::
::::All help and comments welcome.
::::
::::Thank you,
::::
::::Mitch
::::
:::
:::
::All of the readers on this post need only to see Edd's graph.
::
::I know I need at least 40 mili volts.
::
::Thank you again Edd, I will keep the post to success.
::
::Mitch
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:
:
Hello Edd,
My impression was that you would be sending me a component for the tone are, lest i misunderstood i shall follow your posts and try to make one.
Let me know?
Mitch
http://www.west-techservices.com/beam.htm