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Tube Identification
11/24/2007 6:26:58 PMJob Goudie
I have an unidentified Canadian Marconi which I’m trying to get working. I’m recapping but can’t identify one of the capacitors. It’s positive end is connected to pin 8 of 50L6, then through a .005uf capacitor to pin 3 of 50L6. The negative is connected to the phono switch and from there to the negative terminal of the on/off switch. This capacitor looks like a regular, paper wrapped capacitor and it looks like "25 mfd at 25 VWDC" is written on the wrapping...Is this realistic, or am I reading it wrong??
Sorry, I can’t help with a schematic but it's a six tube radio with the tube line-up as follows; 35W4, 50L6, 12BA6, 12AV6, 12BA6, 12BE6.
Regards
Job
11/24/2007 7:44:39 PMRadiodoc
Job,

That cap is probably the cathode bypass cap. There is probably a 150-220 Ohm resistor from cathode pin 8 to B minus with this cap across it.

Radiodoc
**********


:I have an unidentified Canadian Marconi which I’m trying to get working. I’m recapping but can’t identify one of the capacitors. It’s positive end is connected to pin 8 of 50L6, then through a .005uf capacitor to pin 3 of 50L6. The negative is connected to the phono switch and from there to the negative terminal of the on/off switch. This capacitor looks like a regular, paper wrapped capacitor and it looks like "25 mfd at 25 VWDC" is written on the wrapping...Is this realistic, or am I reading it wrong??
:Sorry, I can’t help with a schematic but it's a six tube radio with the tube line-up as follows; 35W4, 50L6, 12BA6, 12AV6, 12BA6, 12BE6.
:Regards
:Job

11/24/2007 10:01:53 PMJob
Doc, is that capacitor supposed to be electrolytic or am I reading it wrong?? It looks like 25 mfd but difficult to say for sure.
Regards

:Job,
:
:That cap is probably the cathode bypass cap. There is probably a 150-220 Ohm resistor from cathode pin 8 to B minus with this cap across it.
:
:Radiodoc
:**********
:
:
::I have an unidentified Canadian Marconi which I’m trying to get working. I’m recapping but can’t identify one of the capacitors. It’s positive end is connected to pin 8 of 50L6, then through a .005uf capacitor to pin 3 of 50L6. The negative is connected to the phono switch and from there to the negative terminal of the on/off switch. This capacitor looks like a regular, paper wrapped capacitor and it looks like "25 mfd at 25 VWDC" is written on the wrapping...Is this realistic, or am I reading it wrong??
::Sorry, I can’t help with a schematic but it's a six tube radio with the tube line-up as follows; 35W4, 50L6, 12BA6, 12AV6, 12BA6, 12BE6.
::Regards
::Job

11/24/2007 10:20:17 PMRadiodoc
Job,

Yes. The plus on the cap goes to the cathode pin 8 on the socket and the minus goes to B minus. Be careful of polarity with all electrolytics (non-polarized caps an exception). The metal tube (covered with plastic/vinyl) is the minus and the end with the plastic/rubber insulator with the wire feeding thru is the positive. There are some radios that use multi-sectioned power supply caps that also contain the output tube cathode bypass cap in the multi-section cap can or paper tube.

Radiodoc
**********


:Doc, is that capacitor supposed to be electrolytic or am I reading it wrong?? It looks like 25 mfd but difficult to say for sure.
:Regards
:
:
:
::Job,
::
::That cap is probably the cathode bypass cap. There is probably a 150-220 Ohm resistor from cathode pin 8 to B minus with this cap across it.
::
::Radiodoc
::**********
::
::
:::I have an unidentified Canadian Marconi which I’m trying to get working. I’m recapping but can’t identify one of the capacitors. It’s positive end is connected to pin 8 of 50L6, then through a .005uf capacitor to pin 3 of 50L6. The negative is connected to the phono switch and from there to the negative terminal of the on/off switch. This capacitor looks like a regular, paper wrapped capacitor and it looks like "25 mfd at 25 VWDC" is written on the wrapping...Is this realistic, or am I reading it wrong??
:::Sorry, I can’t help with a schematic but it's a six tube radio with the tube line-up as follows; 35W4, 50L6, 12BA6, 12AV6, 12BA6, 12BE6.
:::Regards
:::Job

11/25/2007 12:04:06 AMJob
Thanks.


:Job,
:
:Yes. The plus on the cap goes to the cathode pin 8 on the socket and the minus goes to B minus. Be careful of polarity with all electrolytics (non-polarized caps an exception). The metal tube (covered with plastic/vinyl) is the minus and the end with the plastic/rubber insulator with the wire feeding thru is the positive. There are some radios that use multi-sectioned power supply caps that also contain the output tube cathode bypass cap in the multi-section cap can or paper tube.
:
:Radiodoc
:**********
:
:
::Doc, is that capacitor supposed to be electrolytic or am I reading it wrong?? It looks like 25 mfd but difficult to say for sure.
::Regards
::
::
::
:::Job,
:::
:::That cap is probably the cathode bypass cap. There is probably a 150-220 Ohm resistor from cathode pin 8 to B minus with this cap across it.
:::
:::Radiodoc
:::**********
:::
:::
::::I have an unidentified Canadian Marconi which I’m trying to get working. I’m recapping but can’t identify one of the capacitors. It’s positive end is connected to pin 8 of 50L6, then through a .005uf capacitor to pin 3 of 50L6. The negative is connected to the phono switch and from there to the negative terminal of the on/off switch. This capacitor looks like a regular, paper wrapped capacitor and it looks like "25 mfd at 25 VWDC" is written on the wrapping...Is this realistic, or am I reading it wrong??
::::Sorry, I can’t help with a schematic but it's a six tube radio with the tube line-up as follows; 35W4, 50L6, 12BA6, 12AV6, 12BA6, 12BE6.
::::Regards
::::Job



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