Zenith 6J322 resistor value

7/10/2008 2:48:17 PMJohn Hof

Hi. I'm working on a Zenith 6J322 and need to know the value of the resistor that is in series with the two dial lamps. Its just left of the dial lamps in the middle of the schematic. On the schematic on this site, I can't read the resistor number. Could someone with hard copy of the Ryder's manual do me a big favor and look that up? Its on page 9-19. I really would appreciate it,
John.

7/10/2008 3:44:41 PMDoug Criner

John, here is the schematic: http://www.nostalgiaair.org/PagesByModel/139/M0025139.pdf

I don't have an original Ryders, but you can calculate the required reisistor size.

The ballast resistor and the two dial lamps are across the 6.3-V filament supply. Identify the dial lamp type, and look up their voltage and current rating here, under "References."

The resistor needs to drop the difference between 6.3V and double the individual lamp voltage. Select resistor wattage based on I^2R, but double it for safety.

You could use 3.2-V lamps instead of what's there. Another approach would be to substitute 6.3-V lamps, but put them in parallel. Either way, no resistor needed.

:Hi. I'm working on a Zenith 6J322 and need to know the value of the resistor that is in series with the two dial lamps. Its just left of the dial lamps in the middle of the schematic. On the schematic on this site, I can't read the resistor number. Could someone with hard copy of the Ryder's manual do me a big favor and look that up? Its on page 9-19. I really would appreciate it,
:John.

7/10/2008 6:33:54 PMeasyrider8

A 15 ohm 5 watt should work fine.

Dave

:John, here is the schematic: http://www.nostalgiaair.org/PagesByModel/139/M0025139.pdf
:
:I don't have an original Ryders, but you can calculate the required reisistor size.
:
:The ballast resistor and the two dial lamps are across the 6.3-V filament supply. Identify the dial lamp type, and look up their voltage and current rating here, under "References."
:
:The resistor needs to drop the difference between 6.3V and double the individual lamp voltage. Select resistor wattage based on I^2R, but double it for safety.
:
:You could use 3.2-V lamps instead of what's there. Another approach would be to substitute 6.3-V lamps, but put them in parallel. Either way, no resistor needed.
:
:
::Hi. I'm working on a Zenith 6J322 and need to know the value of the resistor that is in series with the two dial lamps. Its just left of the dial lamps in the middle of the schematic. On the schematic on this site, I can't read the resistor number. Could someone with hard copy of the Ryder's manual do me a big favor and look that up? Its on page 9-19. I really would appreciate it,
::John.

7/11/2008 10:41:44 AMNorm Leal

The resistor is there to give lamps longer life. It will drop a little voltage and reduce turn on surge. Dave's suggestion of 15 ohms will work but drop lots of voltage. Lamps will be dim If the original lamps draw .25 amps 15 ohms will drop 3.75 volts.

Could eliminate the resistor or use a very small value. An ohm or two would be enough. Then you wouldn't need 5 watts either.

Norm

:A 15 ohm 5 watt should work fine.
:
:Dave
:
:
:
::John, here is the schematic: http://www.nostalgiaair.org/PagesByModel/139/M0025139.pdf
::
::I don't have an original Ryders, but you can calculate the required reisistor size.
::
::The ballast resistor and the two dial lamps are across the 6.3-V filament supply. Identify the dial lamp type, and look up their voltage and current rating here, under "References."
::
::The resistor needs to drop the difference between 6.3V and double the individual lamp voltage. Select resistor wattage based on I^2R, but double it for safety.
::
::You could use 3.2-V lamps instead of what's there. Another approach would be to substitute 6.3-V lamps, but put them in parallel. Either way, no resistor needed.
::
::
:::Hi. I'm working on a Zenith 6J322 and need to know the value of the resistor that is in series with the two dial lamps. Its just left of the dial lamps in the middle of the schematic. On the schematic on this site, I can't read the resistor number. Could someone with hard copy of the Ryder's manual do me a big favor and look that up? Its on page 9-19. I really would appreciate it,
:::John.

7/11/2008 10:43:50 AMNorm Leal

If lamps are #48 or #49 then a larger resistor would be needed. These are for battery radios and only rated 2 volts @ 60 ma.

Norm

:Hi
:
: The resistor is there to give lamps longer life. It will drop a little voltage and reduce turn on surge. Dave's suggestion of 15 ohms will work but drop lots of voltage. Lamps will be dim If the original lamps draw .25 amps 15 ohms will drop 3.75 volts.
:
: Could eliminate the resistor or use a very small value. An ohm or two would be enough. Then you wouldn't need 5 watts either.
:
:Norm
:
::A 15 ohm 5 watt should work fine.
::
::Dave
::
::
::
:::John, here is the schematic: http://www.nostalgiaair.org/PagesByModel/139/M0025139.pdf
:::
:::I don't have an original Ryders, but you can calculate the required reisistor size.
:::
:::The ballast resistor and the two dial lamps are across the 6.3-V filament supply. Identify the dial lamp type, and look up their voltage and current rating here, under "References."
:::
:::The resistor needs to drop the difference between 6.3V and double the individual lamp voltage. Select resistor wattage based on I^2R, but double it for safety.
:::
:::You could use 3.2-V lamps instead of what's there. Another approach would be to substitute 6.3-V lamps, but put them in parallel. Either way, no resistor needed.
:::
:::
::::Hi. I'm working on a Zenith 6J322 and need to know the value of the resistor that is in series with the two dial lamps. Its just left of the dial lamps in the middle of the schematic. On the schematic on this site, I can't read the resistor number. Could someone with hard copy of the Ryder's manual do me a big favor and look that up? Its on page 9-19. I really would appreciate it,
::::John.

7/11/2008 3:08:21 PMJohn Hof

Thanks so much for the help guys. The bulbs are 2.9V, .17A (#291). The only resistor on the schematic that comes close to your numbers is R15--a 13 ohm wirewound. I had a 15 ohm 5 watt resistor, so I tried it. The filament voltage is 7.5V and the voltage across just the bulbs is 5V, so the resistor is dropping about 2.5V. My new concern is that this filament voltage is pretty high. When I remove one of the bulbs, the voltage goes up to 7.8V. Any ideas what I should do? Again, thank you very much.
John

:If lamps are #48 or #49 then a larger resistor would be needed. These are for battery radios and only rated 2 volts @ 60 ma.
:
:Norm
:
::Hi
::
:: The resistor is there to give lamps longer life. It will drop a little voltage and reduce turn on surge. Dave's suggestion of 15 ohms will work but drop lots of voltage. Lamps will be dim If the original lamps draw .25 amps 15 ohms will drop 3.75 volts.
::
:: Could eliminate the resistor or use a very small value. An ohm or two would be enough. Then you wouldn't need 5 watts either.
::
::Norm
::
:::A 15 ohm 5 watt should work fine.
:::
:::Dave
:::
:::
:::
::::John, here is the schematic: http://www.nostalgiaair.org/PagesByModel/139/M0025139.pdf
::::
::::I don't have an original Ryders, but you can calculate the required reisistor size.
::::
::::The ballast resistor and the two dial lamps are across the 6.3-V filament supply. Identify the dial lamp type, and look up their voltage and current rating here, under "References."
::::
::::The resistor needs to drop the difference between 6.3V and double the individual lamp voltage. Select resistor wattage based on I^2R, but double it for safety.
::::
::::You could use 3.2-V lamps instead of what's there. Another approach would be to substitute 6.3-V lamps, but put them in parallel. Either way, no resistor needed.
::::
::::
:::::Hi. I'm working on a Zenith 6J322 and need to know the value of the resistor that is in series with the two dial lamps. Its just left of the dial lamps in the middle of the schematic. On the schematic on this site, I can't read the resistor number. Could someone with hard copy of the Ryder's manual do me a big favor and look that up? Its on page 9-19. I really would appreciate it,
:::::John.

7/11/2008 3:47:12 PMNorm Leal

Hi John

Don't worry about filament voltage being high with a lamp removed. With the lamp removed you will see full voltage. The resistor won't drop anything without a load.

Norm

:Thanks so much for the help guys. The bulbs are 2.9V, .17A (#291). The only resistor on the schematic that comes close to your numbers is R15--a 13 ohm wirewound. I had a 15 ohm 5 watt resistor, so I tried it. The filament voltage is 7.5V and the voltage across just the bulbs is 5V, so the resistor is dropping about 2.5V. My new concern is that this filament voltage is pretty high. When I remove one of the bulbs, the voltage goes up to 7.8V. Any ideas what I should do? Again, thank you very much.
:John
:
::If lamps are #48 or #49 then a larger resistor would be needed. These are for battery radios and only rated 2 volts @ 60 ma.
::
::Norm
::
:::Hi
:::
::: The resistor is there to give lamps longer life. It will drop a little voltage and reduce turn on surge. Dave's suggestion of 15 ohms will work but drop lots of voltage. Lamps will be dim If the original lamps draw .25 amps 15 ohms will drop 3.75 volts.
:::
::: Could eliminate the resistor or use a very small value. An ohm or two would be enough. Then you wouldn't need 5 watts either.
:::
:::Norm
:::
::::A 15 ohm 5 watt should work fine.
::::
::::Dave
::::
::::
::::
:::::John, here is the schematic: http://www.nostalgiaair.org/PagesByModel/139/M0025139.pdf
:::::
:::::I don't have an original Ryders, but you can calculate the required reisistor size.
:::::
:::::The ballast resistor and the two dial lamps are across the 6.3-V filament supply. Identify the dial lamp type, and look up their voltage and current rating here, under "References."
:::::
:::::The resistor needs to drop the difference between 6.3V and double the individual lamp voltage. Select resistor wattage based on I^2R, but double it for safety.
:::::
:::::You could use 3.2-V lamps instead of what's there. Another approach would be to substitute 6.3-V lamps, but put them in parallel. Either way, no resistor needed.
:::::
:::::
::::::Hi. I'm working on a Zenith 6J322 and need to know the value of the resistor that is in series with the two dial lamps. Its just left of the dial lamps in the middle of the schematic. On the schematic on this site, I can't read the resistor number. Could someone with hard copy of the Ryder's manual do me a big favor and look that up? Its on page 9-19. I really would appreciate it,
::::::John.

7/11/2008 4:26:31 PMEdd

From your info. . . . .sounds like NOTHING needs to be done.

Now, in considering that one DC monitoring probe was to ground and the other one was at the junction of the 15 ohm dropping resistor and the high end of the series strung lamps. When either lamp is removed / fails from the circuit, there is no longer a load imposed upon that resistor so, with no loading, it just lets the full supply level be read out at that point then...excluding the miniscule loading imposed by your metering, which may be in the order of +1,000,000 th of what the lamps loading was.

If you were to consider a mechanical analogy, it would be like getting up to road cruising speed in your car and then holding the accelerator fixed at its setting, but then shifting the transmission into neutral...engine speed is going to sh-o-o-o-o-t up without that loading. The same way with that resistor with its end loading not then being present.

Any-whoo, your prior metering of the complete resistor -series- lamp loop just confirmed ~2.5 V being across each of the lamps..which is a bit of a breather from their having the full spec of 2.9 V across each of them. . . . with there now being an expected lifespan of 'lebenteen years from them .

73's de Edd

7/11/2008 5:10:41 PMDoug Criner(63902:63897)

When John says the heater voltage is 7.5V - is that with all the tubes lighted? If so, then that will shorten the life of the tubes, which are rated 6.3V.
Doug
:Thanks so much for the help guys. The bulbs are 2.9V, .17A (#291). The only resistor on the schematic that comes close to your numbers is R15--a 13 ohm wirewound. I had a 15 ohm 5 watt resistor, so I tried it. The filament voltage is 7.5V and the voltage across just the bulbs is 5V, so the resistor is dropping about 2.5V. My new concern is that this filament voltage is pretty high. When I remove one of the bulbs, the voltage goes up to 7.8V. Any ideas what I should do? Again, thank you very much.
:John
:
::If lamps are #48 or #49 then a larger resistor would be needed. These are for battery radios and only rated 2 volts @ 60 ma.
::
::Norm
::
:::Hi
:::
::: The resistor is there to give lamps longer life. It will drop a little voltage and reduce turn on surge. Dave's suggestion of 15 ohms will work but drop lots of voltage. Lamps will be dim If the original lamps draw .25 amps 15 ohms will drop 3.75 volts.
:::
::: Could eliminate the resistor or use a very small value. An ohm or two would be enough. Then you wouldn't need 5 watts either.
:::
:::Norm
:::
::::A 15 ohm 5 watt should work fine.
::::
::::Dave
::::
::::
::::
:::::John, here is the schematic: http://www.nostalgiaair.org/PagesByModel/139/M0025139.pdf
:::::
:::::I don't have an original Ryders, but you can calculate the required reisistor size.
:::::
:::::The ballast resistor and the two dial lamps are across the 6.3-V filament supply. Identify the dial lamp type, and look up their voltage and current rating here, under "References."
:::::
:::::The resistor needs to drop the difference between 6.3V and double the individual lamp voltage. Select resistor wattage based on I^2R, but double it for safety.
:::::
:::::You could use 3.2-V lamps instead of what's there. Another approach would be to substitute 6.3-V lamps, but put them in parallel. Either way, no resistor needed.
:::::
:::::
::::::Hi. I'm working on a Zenith 6J322 and need to know the value of the resistor that is in series with the two dial lamps. Its just left of the dial lamps in the middle of the schematic. On the schematic on this site, I can't read the resistor number. Could someone with hard copy of the Ryder's manual do me a big favor and look that up? Its on page 9-19. I really would appreciate it,
::::::John.

7/11/2008 5:53:51 PMJohnhof(63905:63902)

Sorry if I wasn't clear--I'm measuring 7.5 volts with all tubes and lamps lit (measured at pins 2 and 7 of an output tube if that helps make it clear). I realize that the best way to drop this would be a step-down transformer, but is it also an option to put a resistor in series with the filaments? If so, any guess on the value? Thanks again,
John
:When John says the heater voltage is 7.5V - is that with all the tubes lighted? If so, then that will shorten the life of the tubes, which are rated 6.3V.
:Doug
:
::Thanks so much for the help guys. The bulbs are 2.9V, .17A (#291). The only resistor on the schematic that comes close to your numbers is R15--a 13 ohm wirewound. I had a 15 ohm 5 watt resistor, so I tried it. The filament voltage is 7.5V and the voltage across just the bulbs is 5V, so the resistor is dropping about 2.5V. My new concern is that this filament voltage is pretty high. When I remove one of the bulbs, the voltage goes up to 7.8V. Any ideas what I should do? Again, thank you very much.
::John
::
:::If lamps are #48 or #49 then a larger resistor would be needed. These are for battery radios and only rated 2 volts @ 60 ma.
:::
:::Norm
:::
::::Hi
::::
:::: The resistor is there to give lamps longer life. It will drop a little voltage and reduce turn on surge. Dave's suggestion of 15 ohms will work but drop lots of voltage. Lamps will be dim If the original lamps draw .25 amps 15 ohms will drop 3.75 volts.
::::
:::: Could eliminate the resistor or use a very small value. An ohm or two would be enough. Then you wouldn't need 5 watts either.
::::
::::Norm
::::
:::::A 15 ohm 5 watt should work fine.
:::::
:::::Dave
:::::
:::::
:::::
::::::John, here is the schematic: http://www.nostalgiaair.org/PagesByModel/139/M0025139.pdf
::::::
::::::I don't have an original Ryders, but you can calculate the required reisistor size.
::::::
::::::The ballast resistor and the two dial lamps are across the 6.3-V filament supply. Identify the dial lamp type, and look up their voltage and current rating here, under "References."
::::::
::::::The resistor needs to drop the difference between 6.3V and double the individual lamp voltage. Select resistor wattage based on I^2R, but double it for safety.
::::::
::::::You could use 3.2-V lamps instead of what's there. Another approach would be to substitute 6.3-V lamps, but put them in parallel. Either way, no resistor needed.
::::::
::::::
:::::::Hi. I'm working on a Zenith 6J322 and need to know the value of the resistor that is in series with the two dial lamps. Its just left of the dial lamps in the middle of the schematic. On the schematic on this site, I can't read the resistor number. Could someone with hard copy of the Ryder's manual do me a big favor and look that up? Its on page 9-19. I really would appreciate it,
:::::::John.

7/11/2008 7:52:27 PMEdd(63908:63905)

Hmmm. . . ahhh so. . . .So the whole filament supply is up that much. In that case, how about the AC line voltage that you are putting into it since that was probably coming at a lower level in olden times, specifically the spec on the schematic is referencing 110 VAC input.

Hmmmm now.... if you were now inputting 126VAC..ya da ya da ....

Also in consulting the voltage chart for the unit I see a max high level of 112 VDC main B+ on the output tubes along with a lower 108 level. If you meter these voltages ...are they up in a like proportional value as that filament supply voltage is ? .

73's de Edd

7/11/2008 9:01:53 PMDoug Criner(63910:63908)

First, I would add a CL-90 inrush limiter to the AC line supply. That will cut the line voltage by a couple of volts and save wear and tear on the tubes at startup.
But, 7.5V is too high for your 6.3-V heaters. How sure are you of your meter's calibration?
You should be more worried about your tubes than your dial lamps.
Doug

7/12/2008 1:35:43 PMJohn Hof(63919:63910)

Good point Edd- the voltage on the plate of the output tube(s) is 129V (should be 108). I think this answers my question about what to do--I need to put a step down transformer on the line input to drop it by about 20% which will address both the B+ and the filament over-voltage. The inrush doesn't look bad at all, nice slow move up to the warm voltage (the 6ZY5 rectifier does not have a directly heated K). And yes, the dial lamp issue is resolved at this point. Thanks a bunch guys, you've been a great help,
John
:First, I would add a CL-90 inrush limiter to the AC line supply. That will cut the line voltage by a couple of volts and save wear and tear on the tubes at startup.
:
:But, 7.5V is too high for your 6.3-V heaters. How sure are you of your meter's calibration?
:
:You should be more worried about your tubes than your dial lamps.
:Doug

7/12/2008 7:10:10 PMDoug Criner(63932:63919)

Finding a suitable step-down xfmr (1.2:1) may be difficult? This might be a good application for a buck-boost xfmr setup.
Doug
:Good point Edd- the voltage on the plate of the output tube(s) is 129V (should be 108). I think this answers my question about what to do--I need to put a step down transformer on the line input to drop it by about 20% which will address both the B+ and the filament over-voltage.

7/12/2008 11:30:18 PMJohn Hof(63942:63932)

Yeah, if I remember correctly, the input goes to the primary like usual, then you crosswire one side of the primary to the other side of the secondary and the output is the other sides of the primary and the secondary not crosswired. By my calculations, I would need a filament transformer with a 115v primary and about a 19v secondary to get the 1:1.2 drop I'm looking for. Does that all sound right? What kind of amperage rating would I need for this transformer? Oh, by the way, I never addressed your question about my measurements. I have a Fluke 177 DMM and I would think that it's accurate. Hey, thanks so much for the help,
John
:Finding a suitable step-down xfmr (1.2:1) may be difficult? This might be a good application for a buck-boost xfmr setup.
:Doug
:
::Good point Edd- the voltage on the plate of the output tube(s) is 129V (should be 108). I think this answers my question about what to do--I need to put a step down transformer on the line input to drop it by about 20% which will address both the B+ and the filament over-voltage.

7/13/2008 2:51:20 PMDoug Criner(63951:63942)

Another approach would be to put a dropping resistor or, better yet, an unpolarized cap in series with the filament supply. You don't really need to worry too much about the high B+.
Doug
:Yeah, if I remember correctly, the input goes to the primary like usual, then you crosswire one side of the primary to the other side of the secondary and the output is the other sides of the primary and the secondary not crosswired. By my calculations, I would need a filament transformer with a 115v primary and about a 19v secondary to get the 1:1.2 drop I'm looking for. Does that all sound right? What kind of amperage rating would I need for this transformer? Oh, by the way, I never addressed your question about my measurements. I have a Fluke 177 DMM and I would think that it's accurate. Hey, thanks so much for the help,
:John
:
::Finding a suitable step-down xfmr (1.2:1) may be difficult? This might be a good application for a buck-boost xfmr setup.
::Doug
::
:::Good point Edd- the voltage on the plate of the output tube(s) is 129V (should be 108). I think this answers my question about what to do--I need to put a step down transformer on the line input to drop it by about 20% which will address both the B+ and the filament over-voltage.

7/13/2008 3:09:31 PMJohn Hof(63952:63951)

So, how would I calulate the values for that resistor or cap? thanks again,
John
:Another approach would be to put a dropping resistor or, better yet, an unpolarized cap in series with the filament supply. You don't really need to worry too much about the high B+.
:Doug
:
::Yeah, if I remember correctly, the input goes to the primary like usual, then you crosswire one side of the primary to the other side of the secondary and the output is the other sides of the primary and the secondary not crosswired. By my calculations, I would need a filament transformer with a 115v primary and about a 19v secondary to get the 1:1.2 drop I'm looking for. Does that all sound right? What kind of amperage rating would I need for this transformer? Oh, by the way, I never addressed your question about my measurements. I have a Fluke 177 DMM and I would think that it's accurate. Hey, thanks so much for the help,
::John
::
:::Finding a suitable step-down xfmr (1.2:1) may be difficult? This might be a good application for a buck-boost xfmr setup.
:::Doug
:::
::::Good point Edd- the voltage on the plate of the output tube(s) is 129V (should be 108). I think this answers my question about what to do--I need to put a step down transformer on the line input to drop it by about 20% which will address both the B+ and the filament over-voltage.

7/13/2008 4:39:59 PMDoug Criner(63956:63952)

With reference to a tube manual or on-line tube data, figure the total current supplied by the filament winding (including the dial lamps).
For a dropping resistor, size R=V/I, where V is the voltage drop you are looking for. Min wattage = 2xVxI. The resistor will get hot, so need to mount it on top of the chassis?
A dropping cap won't get hot. But to figure the size, need to use trigonometry - since the volage across the cap is 90 deg out of phase with the voltage across the tubes/lamps. There is a website somewhere that does the math for you, but I've lost track of it. Maybe somebody here can direct you to it?
Otherwise, draw the voltage trangle, and compute the cap's voltage drop using trig. Compute capacitance from the equation V= I/(2 x pi x 60 x C). It will probably be a few microfarads.
Doug
:So, how would I calulate the values for that resistor or cap? thanks again,
:John
:
::Another approach would be to put a dropping resistor or, better yet, an unpolarized cap in series with the filament supply. You don't really need to worry too much about the high B+.
::Doug
::

7/13/2008 7:05:45 PMJohn Hof(63959:63956)

That's just what I need Doug, thank you very much. You have been more than helpful.
John
:With reference to a tube manual or on-line tube data, figure the total current supplied by the filament winding (including the dial lamps).
:
:For a dropping resistor, size R=V/I, where V is the voltage drop you are looking for. Min wattage = 2xVxI. The resistor will get hot, so need to mount it on top of the chassis?
:
:A dropping cap won't get hot. But to figure the size, need to use trigonometry - since the volage across the cap is 90 deg out of phase with the voltage across the tubes/lamps. There is a website somewhere that does the math for you, but I've lost track of it. Maybe somebody here can direct you to it?
:
:Otherwise, draw the voltage trangle, and compute the cap's voltage drop using trig. Compute capacitance from the equation V= I/(2 x pi x 60 x C). It will probably be a few microfarads.
:Doug
:
::So, how would I calulate the values for that resistor or cap? thanks again,
::John
::
:::Another approach would be to put a dropping resistor or, better yet, an unpolarized cap in series with the filament supply. You don't really need to worry too much about the high B+.
:::Doug
:::
: