No voltage in D point of the scheme I tested the choke (part 27) was open. Someone know where I can find another or how many coils and of what diameter of thread in it?

Hi Steafno

Check this site for Philco part indentification:

http://www.philcorepairbench.com/

You are lucky the choke was open rather than speaker field. If you don't find exact specifications use a choke of 5 - 10 henry @ 75 ma or more.

Norm

:No voltage in D point of the scheme I tested the choke (part 27) was open. Someone know where I can find another or how many coils and of what diameter of thread in it?

Many thanks, but is very difficult found it in Italy and I would like to personally rewind the spool but I don't know how much coils in it and the diameter of the copper......

:Hi Steafno
:
: Check this site for Philco part indentification:
:
:http://www.philcorepairbench.com/
:
: You are lucky the choke was open rather than speaker field. If you don't find exact specifications use a choke of 5 - 10 henry @ 75 ma or more.
:
:Norm
:
::No voltage in D point of the scheme I tested the choke (part 27) was open. Someone know where I can find another or how many coils and of what diameter of thread in it?

....this is the choke of 6 pin filter condenser block not the speker choker....

:Many thanks, but is very difficult found it in Italy and I would like to personally rewind the spool but I don't know how much coils in it and the diameter of the copper......
:
::Hi Steafno
::
:: Check this site for Philco part indentification:
::
::http://www.philcorepairbench.com/
::
:: You are lucky the choke was open rather than speaker field. If you don't find exact specifications use a choke of 5 - 10 henry @ 75 ma or more.
::
::Norm
::
:::No voltage in D point of the scheme I tested the choke (part 27) was open. Someone know where I can find another or how many coils and of what diameter of thread in it?

Stefano: You can unwind a little of the coil and measure the wire diameter with a micrometer - or just compare to wire of known gauge. I'll just guess that it's around #26 to #30 AWG (American Wire Gauge).

You might check to see if the choke is open right at one of the connections - that would be a relatively simple fix.

Rewinding the coil is not for the feint of heart. Personally, I would just replace the coil with a resistor, say 500 ohms, 10W. If the DC voltage to the detector plate, which is supposed to be 130V, winds up being too high or low, you can adjust the resistance, accordingly.

If you do decide to rewind the coil, you can go to Dr. Coyle to estimate the required number of turns to get the 50-10H suggested by Norm: http://www.crystalradio.net/professorcoyle/

The inductance of the coil isn't at all critical, but you do need to have the resistance of the coil to reasonably close, since that is what determines the plate voltage to the detector. But, if your coil's resistance comes out a little off, you can adjust with a series or parallel power resistor.

If you decide to replace the choke with a resistor, and you wind up with some humm, then you can jack up the size of the filter capacitors a little.
Doug

:....this is the choke of 6 pin filter condenser block not the speker choker....
:
:
::Many thanks, but is very difficult found it in Italy and I would like to personally rewind the spool but I don't know how much coils in it and the diameter of the copper......
::
:::Hi Steafno
:::
::: Check this site for Philco part indentification:
:::
:::http://www.philcorepairbench.com/
:::
::: You are lucky the choke was open rather than speaker field. If you don't find exact specifications use a choke of 5 - 10 henry @ 75 ma or more.
:::
:::Norm
:::
::::No voltage in D point of the scheme I tested the choke (part 27) was open. Someone know where I can find another or how many coils and of what diameter of thread in it?

Is there a part number on the choke? Did you check here: http://www.philcorepairbench.com/choke.htm

:If you do decide to rewind the coil, you can go to Dr. Coyle to estimate the required number of turns to get the 50-10H suggested by Norm: http://www.crystalradio.net/professorcoyle/

Doug:
misplaced zero?... I'm sure you meant 5-10H

Yes, thanks Peter.
Doug

:Doug:
:misplaced zero?... I'm sure you meant 5-10H

The part number is 4231 (11 Henries, 80 milliamperes, 4000 ohms d.c. resistance)

:Stefano: You can unwind a little of the coil and measure the wire diameter with a micrometer - or just compare to wire of known gauge. I'll just guess that it's around #26 to #30 AWG (American Wire Gauge).
:
:You might check to see if the choke is open right at one of the connections - that would be a relatively simple fix.
:
:Rewinding the coil is not for the feint of heart. Personally, I would just replace the coil with a resistor, say 500 ohms, 10W. If the DC voltage to the detector plate, which is supposed to be 130V, winds up being too high or low, you can adjust the resistance, accordingly.
:
:If you do decide to rewind the coil, you can go to Dr. Coyle to estimate the required number of turns to get the 50-10H suggested by Norm: http://www.crystalradio.net/professorcoyle/
:
:The inductance of the coil isn't at all critical, but you do need to have the resistance of the coil to reasonably close, since that is what determines the plate voltage to the detector. But, if your coil's resistance comes out a little off, you can adjust with a series or parallel power resistor.
:
:If you decide to replace the choke with a resistor, and you wind up with some humm, then you can jack up the size of the filter capacitors a little.
:Doug
:
::....this is the choke of 6 pin filter condenser block not the speker choker....
::
::
:::Many thanks, but is very difficult found it in Italy and I would like to personally rewind the spool but I don't know how much coils in it and the diameter of the copper......
:::
::::Hi Steafno
::::
:::: Check this site for Philco part indentification:
::::
::::http://www.philcorepairbench.com/
::::
:::: You are lucky the choke was open rather than speaker field. If you don't find exact specifications use a choke of 5 - 10 henry @ 75 ma or more.
::::
::::Norm
::::
:::::No voltage in D point of the scheme I tested the choke (part 27) was open. Someone know where I can find another or how many coils and of what diameter of thread in it?

If you decide to replace the choke with a power resistor, then use 4K ohm. The calculated wattage of the coil is 26W, but I would use a larger wattage resistor for a safety margin. For example, you could put four 1K, 10W resistors in series, which would give a total of 4K, 40W - which should be plenty.

I think you might be surprised at the number of turns on the coil and the length of wire involved.
Doug

:The part number is 4231 (11 Henries, 80 milliamperes, 4000 ohms d.c. resistance)
:
:

Hi

Are you sure about the resistance? I didn't try to look it up but seems high to me. 4000 ohms at 80 ma drops 320 volts.. Chokes usually have fairly low resistance. 4000 seems high?

Norm

:The part number is 4231 (11 Henries, 80 milliamperes, 4000 ohms d.c. resistance)
:
:
::Stefano: You can unwind a little of the coil and measure the wire diameter with a micrometer - or just compare to wire of known gauge. I'll just guess that it's around #26 to #30 AWG (American Wire Gauge).
::
::You might check to see if the choke is open right at one of the connections - that would be a relatively simple fix.
::
::Rewinding the coil is not for the feint of heart. Personally, I would just replace the coil with a resistor, say 500 ohms, 10W. If the DC voltage to the detector plate, which is supposed to be 130V, winds up being too high or low, you can adjust the resistance, accordingly.
::
::If you do decide to rewind the coil, you can go to Dr. Coyle to estimate the required number of turns to get the 50-10H suggested by Norm: http://www.crystalradio.net/professorcoyle/
::
::The inductance of the coil isn't at all critical, but you do need to have the resistance of the coil to reasonably close, since that is what determines the plate voltage to the detector. But, if your coil's resistance comes out a little off, you can adjust with a series or parallel power resistor.
::
::If you decide to replace the choke with a resistor, and you wind up with some humm, then you can jack up the size of the filter capacitors a little.
::Doug
::
:::....this is the choke of 6 pin filter condenser block not the speker choker....
:::
:::
::::Many thanks, but is very difficult found it in Italy and I would like to personally rewind the spool but I don't know how much coils in it and the diameter of the copper......
::::
:::::Hi Steafno
:::::
::::: Check this site for Philco part indentification:
:::::
:::::http://www.philcorepairbench.com/
:::::
::::: You are lucky the choke was open rather than speaker field. If you don't find exact specifications use a choke of 5 - 10 henry @ 75 ma or more.
:::::
:::::Norm
:::::
::::::No voltage in D point of the scheme I tested the choke (part 27) was open. Someone know where I can find another or how many coils and of what diameter of thread in it?

I se in http://www.philcorepairbench.com/choke.htm for choke part number 4231.......

:Hi
:
: Are you sure about the resistance? I didn't try to look it up but seems high to me. 4000 ohms at 80 ma drops 320 volts.. Chokes usually have fairly low resistance. 4000 seems high?
:
:Norm
:
::The part number is 4231 (11 Henries, 80 milliamperes, 4000 ohms d.c. resistance)
::
::
:::Stefano: You can unwind a little of the coil and measure the wire diameter with a micrometer - or just compare to wire of known gauge. I'll just guess that it's around #26 to #30 AWG (American Wire Gauge).
:::
:::You might check to see if the choke is open right at one of the connections - that would be a relatively simple fix.
:::
:::Rewinding the coil is not for the feint of heart. Personally, I would just replace the coil with a resistor, say 500 ohms, 10W. If the DC voltage to the detector plate, which is supposed to be 130V, winds up being too high or low, you can adjust the resistance, accordingly.
:::
:::If you do decide to rewind the coil, you can go to Dr. Coyle to estimate the required number of turns to get the 50-10H suggested by Norm: http://www.crystalradio.net/professorcoyle/
:::
:::The inductance of the coil isn't at all critical, but you do need to have the resistance of the coil to reasonably close, since that is what determines the plate voltage to the detector. But, if your coil's resistance comes out a little off, you can adjust with a series or parallel power resistor.
:::
:::If you decide to replace the choke with a resistor, and you wind up with some humm, then you can jack up the size of the filter capacitors a little.
:::Doug
:::
::::....this is the choke of 6 pin filter condenser block not the speker choker....
::::
::::
:::::Many thanks, but is very difficult found it in Italy and I would like to personally rewind the spool but I don't know how much coils in it and the diameter of the copper......
:::::
::::::Hi Steafno
::::::
:::::: Check this site for Philco part indentification:
::::::
::::::http://www.philcorepairbench.com/
::::::
:::::: You are lucky the choke was open rather than speaker field. If you don't find exact specifications use a choke of 5 - 10 henry @ 75 ma or more.
::::::
::::::Norm
::::::
:::::::No voltage in D point of the scheme I tested the choke (part 27) was open. Someone know where I can find another or how many coils and of what diameter of thread in it?

I assume that Stefano is reading the model number that's listed on the choke itself and matching it up with the published ratings?

The actual current through the choke looks to be about 42mA (compared to the 80mA that the choke is actually rated for?). That would give a voltage drop through the choke of 42mA x 4K = 168V. Looking at the various transformer ratings shown on the Philco Repair Bench, this might be right to give a 250-V B+ for the plate supply?
Doug

:I se in http://www.philcorepairbench.com/choke.htm for choke part number 4231.......
:
:
::Hi
::
:: Are you sure about the resistance? I didn't try to look it up but seems high to me. 4000 ohms at 80 ma drops 320 volts.. Chokes usually have fairly low resistance. 4000 seems high?
::
::Norm
::
:::The part number is 4231 (11 Henries, 80 milliamperes, 4000 ohms d.c. resistance)
:::
:::
::::Stefano: You can unwind a little of the coil and measure the wire diameter with a micrometer - or just compare to wire of known gauge. I'll just guess that it's around #26 to #30 AWG (American Wire Gauge).
::::
::::You might check to see if the choke is open right at one of the connections - that would be a relatively simple fix.
::::
::::Rewinding the coil is not for the feint of heart. Personally, I would just replace the coil with a resistor, say 500 ohms, 10W. If the DC voltage to the detector plate, which is supposed to be 130V, winds up being too high or low, you can adjust the resistance, accordingly.
::::
::::If you do decide to rewind the coil, you can go to Dr. Coyle to estimate the required number of turns to get the 50-10H suggested by Norm: http://www.crystalradio.net/professorcoyle/
::::
::::The inductance of the coil isn't at all critical, but you do need to have the resistance of the coil to reasonably close, since that is what determines the plate voltage to the detector. But, if your coil's resistance comes out a little off, you can adjust with a series or parallel power resistor.
::::
::::If you decide to replace the choke with a resistor, and you wind up with some humm, then you can jack up the size of the filter capacitors a little.
::::Doug
::::
:::::....this is the choke of 6 pin filter condenser block not the speker choker....
:::::
:::::
::::::Many thanks, but is very difficult found it in Italy and I would like to personally rewind the spool but I don't know how much coils in it and the diameter of the copper......
::::::
:::::::Hi Steafno
:::::::
::::::: Check this site for Philco part indentification:
:::::::
:::::::http://www.philcorepairbench.com/
:::::::
::::::: You are lucky the choke was open rather than speaker field. If you don't find exact specifications use a choke of 5 - 10 henry @ 75 ma or more.
:::::::
:::::::Norm
:::::::
::::::::No voltage in D point of the scheme I tested the choke (part 27) was open. Someone know where I can find another or how many coils and of what diameter of thread in it?

www.tubesandmore.com and www.radiodaze.com will ship internationally (though who knows how corrupt the shipping services get in transit). It will be ideal if you can rewind the choke, but if you can't, I believe that you can obtain a replacement.

Thomas