I AM tryng to repair a 6M632 Deforest Crosley Chassis (1937) for a friend. The origional was a 6D631 Chassis. The only difference is the 632 Chassis has an extra tube, "RF amplifier", otherwise they are the same. The Chassis were available by three different Canadian Manufactures. " Deforest, Rogers and Majestic". The origional Chassis (6D321) had been hit by lighting was was blown to beyond repair. I looked for a suitable donation chassis, and found a
6M632 which would fit in the cabinet, The donor chassis had many issues that would take to long explain here, but was repairable. I put the chassis back to origional configuration, and changed out the wax paper capacitors, electrolytic's and out of tolerance resistors. This set has a electro-magnetic speaker, and testing showed the field coil was about 2200 ohms, and the output transformer had close to 600 ohms. However, when all this work was done, and the set first powered up, the signal only was detectable up to the grid of the output tube 6F6 single stage. checked voltage into and out of the output transformer and it was 320 volts, both sides. Speaker seems to be okay,when ohmed at proper value for 4 ohm secondary side, can hear click on the speaker. Can also hear click on the speaker when that value is ohmed at the primary side. I appear to have no current on the output side of the 6F6. Double checked the circuit on the grid side, including the resistors in that circuit, all okay. trid to lower the grid resistance, because thought the output tube was cut off, but did not make a difference. any other suggestions??
Gerry

From what you describe the audio output section is working. The problem would seem to be one stage back in the detector AF section. If you touch the input grid of the detector grid you should get a loud buzz from the speaker. If not trouble shoot the AF amp.

:From what you describe the audio output section is working. The problem would seem to be one stage back in the detector AF section. If you touch the input grid of the detector grid you should get a loud buzz from the speaker. If not trouble shoot the AF amp.

Hmmmm....not so sure. Have you checked the cathode? With 320 Volts on both sides of the output transformer, the output might not be drawing current. (there should be a SMALL drop across the primary of the transformer) I haven't seen the schematic, but if there is a cathode resistor, there might be an open in that circuit.
Lewis
:

::From what you describe the audio output section is working. The problem would seem to be one stage back in the detector AF section. If you touch the input grid of the detector grid you should get a loud buzz from the speaker. If not trouble shoot the AF amp.
:
:
:Hmmmm....not so sure. Have you checked the cathode? With 320 Volts on both sides of the output transformer, the output might not be drawing current. (there should be a SMALL drop across the primary of the transformer) I haven't seen the schematic, but if there is a cathode resistor, there might be an open in that circuit.
:Lewis
::
:
:

:::From what you describe the audio output section is working. The problem would seem to be one stage back in the detector AF section. If you touch the input grid of the detector grid you should get a loud buzz from the speaker. If not trouble shoot the AF amp.
::
::
::Hmmmm....not so sure. Have you checked the cathode? With 320 Volts on both sides of the output transformer, the output might not be drawing current. (there should be a SMALL drop across the primary of the transformer) I haven't seen the schematic, but if there is a cathode resistor, there might be an open in that circuit.
::Lewis
:::
::
::
:
:
Thanks for your input, Cathode goes straight to ground. Have very carefully checked with ohms meter all speaker plug connections, and everythings okay. I agree with Lewis, The output transformer does not appear to load up and therefore no current. Maybe the primary is shorted out, but if so, why do I read 600 ohms through it? The speaker assembly is from the original chassis that had been hit by lightning.
Gerry

Believe it was mentioned the radio used a 6F6 tube as audio output. Tried a new tube? Has the screen grid voltage on pin 4 been checked. There was mention that the cathode was grounded. Does the control grid pin 5 have the proper minus bias voltage?

Clifton

::::From what you describe the audio output section is working. The problem would seem to be one stage back in the detector AF section. If you touch the input grid of the detector grid you should get a loud buzz from the speaker. If not trouble shoot the AF amp.
:::
:::
:::Hmmmm....not so sure. Have you checked the cathode? With 320 Volts on both sides of the output transformer, the output might not be drawing current. (there should be a SMALL drop across the primary of the transformer) I haven't seen the schematic, but if there is a cathode resistor, there might be an open in that circuit.
:::Lewis
::::
:::
:::
::
::
:Thanks for your input, Cathode goes straight to ground. Have very carefully checked with ohms meter all speaker plug connections, and everythings okay. I agree with Lewis, The output transformer does not appear to load up and therefore no current. Maybe the primary is shorted out, but if so, why do I read 600 ohms through it? The speaker assembly is from the original chassis that had been hit by lightning.
:Gerry
:

Hi Gerry,
I think Clifton is steering ou in a good direction. Check pin 5 on the 6F6. You need negative there, but no too negative, like 7 to 12 volts.

Best Regards,

Bill grimm

:Hi Gerry,
: I think Clifton is steering ou in a good direction. Check pin 5 on the 6F6. You need negative there, but no too negative, like 7 to 12 volts.
:
:Best Regards,
:
:Bill grimm
:
Hi Bill, Thank you for the suggestion, I have checked pin 5, and it is minus 7 volts.
Gerry

:Believe it was mentioned the radio used a 6F6 tube as audio output. Tried a new tube? Has the screen grid voltage on pin 4 been checked. There was mention that the cathode was grounded. Does the control grid pin 5 have the proper minus bias voltage?
:
:Clifton

:Hi, Thanks for your reply, Yes I have tried a new tube, also have checked the continuety between all the pins of the output tube 6F6, and they all check out okay, Have also checked out the speaker plug pins, and all check out okay. Today, I took the speaker plug terminal on the chassis out, and tied a 2000 Ohms resistor across the field coil output pins and put a new single ended output transformer across the B Plus, and tied a bench test speaker to the output. I still had the same results, no current through the 6F6 output tube. Yes, I have tried to lower the Bias resistance on the grid, and it does not seem to make a difference. The screen grid output is the same level as the plate on the output tube voltage. When I had the jury rig output transformer and speaker hooked up today, I used my Heathkit IT-12 Signal Tracer, set to Audio output on the plate of the Detector plate, and touched the grids of the IF tube 6K7, and lost the BC station that was tuned into on the AM Band. This chassis is a Canadian Majestic model "Rodney" "Renown" and "Hood", also included in this chassis lineup are Rogers and DeForest models, the model numbers are 6 ("M" "R" or "D") then 632 respectitely. The best source for Older Canadian Chassis schematic's are from webb site "www.pacifictv.ca". Thank you for your help.
One thing that you have to keep in mind, is the tube numbers. The schematic on the Pacific TV site is a re-draw from the original, and the original schematic shows the tube identies as "Rogers Tubes", which are different than the normal group we are used to dealing with. The tube line up in Rogers tubes reads:
Rectifier, 80. RF amplifier 6K7, Mixer 6A7, IF Amplifier 6K7, Detector 75, and Output 6F6: in What we are normally used to, converts to: Detector 80, RF amplifier 6K7, Mixer 6A8, IF amplifier 6K7, Detector 6Q7, and output 6F6.

:
:::::From what you describe the audio output section is working. The problem would seem to be one stage back in the detector AF section. If you touch the input grid of the detector grid you should get a loud buzz from the speaker. If not trouble shoot the AF amp.
::::
::::
::::Hmmmm....not so sure. Have you checked the cathode? With 320 Volts on both sides of the output transformer, the output might not be drawing current. (there should be a SMALL drop across the primary of the transformer) I haven't seen the schematic, but if there is a cathode resistor, there might be an open in that circuit.
::::Lewis
:::::
::::
::::
:::
:::
::Thanks for your input, Cathode goes straight to ground. Have very carefully checked with ohms meter all speaker plug connections, and everythings okay. I agree with Lewis, The output transformer does not appear to load up and therefore no current. Maybe the primary is shorted out, but if so, why do I read 600 ohms through it? The speaker assembly is from the original chassis that had been hit by lightning.
::Gerry
::
:
:

Gerry,

Not sure if I under stand your statement that you put a single-ended OPT across the B+. The transformer should be connected one end of the OPT primary to pin 3 of the 6F6 socket and the other end to B+.

Clifton

::Believe it was mentioned the radio used a 6F6 tube as audio output. Tried a new tube? Has the screen grid voltage on pin 4 been checked. There was mention that the cathode was grounded. Does the control grid pin 5 have the proper minus bias voltage?
::
::Clifton
:
::Hi, Thanks for your reply, Yes I have tried a new tube, also have checked the continuety between all the pins of the output tube 6F6, and they all check out okay, Have also checked out the speaker plug pins, and all check out okay. Today, I took the speaker plug terminal on the chassis out, and tied a 2000 Ohms resistor across the field coil output pins and put a new single ended output transformer across the B Plus, and tied a bench test speaker to the output. I still had the same results, no current through the 6F6 output tube. Yes, I have tried to lower the Bias resistance on the grid, and it does not seem to make a difference. The screen grid output is the same level as the plate on the output tube voltage. When I had the jury rig output transformer and speaker hooked up today, I used my Heathkit IT-12 Signal Tracer, set to Audio output on the plate of the Detector plate, and touched the grids of the IF tube 6K7, and lost the BC station that was tuned into on the AM Band. This chassis is a Canadian Majestic model "Rodney" "Renown" and "Hood", also included in this chassis lineup are Rogers and DeForest models, the model numbers are 6 ("M" "R" or "D") then 632 respectitely. The best source for Older Canadian Chassis schematic's are from webb site "www.pacifictv.ca". Thank you for your help.
:One thing that you have to keep in mind, is the tube numbers. The schematic on the Pacific TV site is a re-draw from the original, and the original schematic shows the tube identies as "Rogers Tubes", which are different than the normal group we are used to dealing with. The tube line up in Rogers tubes reads:
:Rectifier, 80. RF amplifier 6K7, Mixer 6A7, IF Amplifier 6K7, Detector 75, and Output 6F6: in What we are normally used to, converts to: Detector 80, RF amplifier 6K7, Mixer 6A8, IF amplifier 6K7, Detector 6Q7, and output 6F6.
:
::
::::::From what you describe the audio output section is working. The problem would seem to be one stage back in the detector AF section. If you touch the input grid of the detector grid you should get a loud buzz from the speaker. If not trouble shoot the AF amp.
:::::
:::::
:::::Hmmmm....not so sure. Have you checked the cathode? With 320 Volts on both sides of the output transformer, the output might not be drawing current. (there should be a SMALL drop across the primary of the transformer) I haven't seen the schematic, but if there is a cathode resistor, there might be an open in that circuit.
:::::Lewis
::::::
:::::
:::::
::::
::::
:::Thanks for your input, Cathode goes straight to ground. Have very carefully checked with ohms meter all speaker plug connections, and everythings okay. I agree with Lewis, The output transformer does not appear to load up and therefore no current. Maybe the primary is shorted out, but if so, why do I read 600 ohms through it? The speaker assembly is from the original chassis that had been hit by lightning.
:::Gerry
:::
::
::
:
:

:Gerry,
:
:Not sure if I under stand your statement that you put a single-ended OPT across the B+. The transformer should be connected one end of the OPT primary to pin 3 of the 6F6 socket and the other end to B+.
:
:Clifton
:Thanks Clifton, Your right, the OPT was hooked up properly off the plate of the 6F6 and the other side to the positive side of the electrolytics and screen gride of 6F6.
Gerry
:::Believe it was mentioned the radio used a 6F6 tube as audio output. Tried a new tube? Has the screen grid voltage on pin 4 been checked. There was mention that the cathode was grounded. Does the control grid pin 5 have the proper minus bias voltage?
:::
:::Clifton
::
:::Hi, Thanks for your reply, Yes I have tried a new tube, also have checked the continuety between all the pins of the output tube 6F6, and they all check out okay, Have also checked out the speaker plug pins, and all check out okay. Today, I took the speaker plug terminal on the chassis out, and tied a 2000 Ohms resistor across the field coil output pins and put a new single ended output transformer across the B Plus, and tied a bench test speaker to the output. I still had the same results, no current through the 6F6 output tube. Yes, I have tried to lower the Bias resistance on the grid, and it does not seem to make a difference. The screen grid output is the same level as the plate on the output tube voltage. When I had the jury rig output transformer and speaker hooked up today, I used my Heathkit IT-12 Signal Tracer, set to Audio output on the plate of the Detector plate, and touched the grids of the IF tube 6K7, and lost the BC station that was tuned into on the AM Band. This chassis is a Canadian Majestic model "Rodney" "Renown" and "Hood", also included in this chassis lineup are Rogers and DeForest models, the model numbers are 6 ("M" "R" or "D") then 632 respectitely. The best source for Older Canadian Chassis schematic's are from webb site "www.pacifictv.ca". Thank you for your help.
::One thing that you have to keep in mind, is the tube numbers. The schematic on the Pacific TV site is a re-draw from the original, and the original schematic shows the tube identies as "Rogers Tubes", which are different than the normal group we are used to dealing with. The tube line up in Rogers tubes reads:
::Rectifier, 80. RF amplifier 6K7, Mixer 6A7, IF Amplifier 6K7, Detector 75, and Output 6F6: in What we are normally used to, converts to: Detector 80, RF amplifier 6K7, Mixer 6A8, IF amplifier 6K7, Detector 6Q7, and output 6F6.
::
:::
:::::::From what you describe the audio output section is working. The problem would seem to be one stage back in the detector AF section. If you touch the input grid of the detector grid you should get a loud buzz from the speaker. If not trouble shoot the AF amp.
::::::
::::::
::::::Hmmmm....not so sure. Have you checked the cathode? With 320 Volts on both sides of the output transformer, the output might not be drawing current. (there should be a SMALL drop across the primary of the transformer) I haven't seen the schematic, but if there is a cathode resistor, there might be an open in that circuit.
::::::Lewis
:::::::
::::::
::::::
:::::
:::::
::::Thanks for your input, Cathode goes straight to ground. Have very carefully checked with ohms meter all speaker plug connections, and everythings okay. I agree with Lewis, The output transformer does not appear to load up and therefore no current. Maybe the primary is shorted out, but if so, why do I read 600 ohms through it? The speaker assembly is from the original chassis that had been hit by lightning.
::::Gerry
::::
:::
:::
::
::
:
:

Gerry,

Probably too obvious but are you using a 6F6 G/GT (glass) or 6F6 (metal) tube? One could see the filament working in a glass tube, but not a metal one. If using a metal tube, does it get warm. If not, there may be a problem with one of the socket filament contacts 2 or 7.

If the tube has B+ voltage on the plate, screen grid and minus bias on the control grid, and with a subbed in OPT and the filament is lighted, there should be some kind of sound out of the OPT.

Clifton

::Gerry,
::
::Not sure if I under stand your statement that you put a single-ended OPT across the B+. The transformer should be connected one end of the OPT primary to pin 3 of the 6F6 socket and the other end to B+.
::
::Clifton
::Thanks Clifton, Your right, the OPT was hooked up properly off the plate of the 6F6 and the other side to the positive side of the electrolytics and screen gride of 6F6.
:Gerry
::::Believe it was mentioned the radio used a 6F6 tube as audio output. Tried a new tube? Has the screen grid voltage on pin 4 been checked. There was mention that the cathode was grounded. Does the control grid pin 5 have the proper minus bias voltage?
::::
::::Clifton
:::
::::Hi, Thanks for your reply, Yes I have tried a new tube, also have checked the continuety between all the pins of the output tube 6F6, and they all check out okay, Have also checked out the speaker plug pins, and all check out okay. Today, I took the speaker plug terminal on the chassis out, and tied a 2000 Ohms resistor across the field coil output pins and put a new single ended output transformer across the B Plus, and tied a bench test speaker to the output. I still had the same results, no current through the 6F6 output tube. Yes, I have tried to lower the Bias resistance on the grid, and it does not seem to make a difference. The screen grid output is the same level as the plate on the output tube voltage. When I had the jury rig output transformer and speaker hooked up today, I used my Heathkit IT-12 Signal Tracer, set to Audio output on the plate of the Detector plate, and touched the grids of the IF tube 6K7, and lost the BC station that was tuned into on the AM Band. This chassis is a Canadian Majestic model "Rodney" "Renown" and "Hood", also included in this chassis lineup are Rogers and DeForest models, the model numbers are 6 ("M" "R" or "D") then 632 respectitely. The best source for Older Canadian Chassis schematic's are from webb site "www.pacifictv.ca". Thank you for your help.
:::One thing that you have to keep in mind, is the tube numbers. The schematic on the Pacific TV site is a re-draw from the original, and the original schematic shows the tube identies as "Rogers Tubes", which are different than the normal group we are used to dealing with. The tube line up in Rogers tubes reads:
:::Rectifier, 80. RF amplifier 6K7, Mixer 6A7, IF Amplifier 6K7, Detector 75, and Output 6F6: in What we are normally used to, converts to: Detector 80, RF amplifier 6K7, Mixer 6A8, IF amplifier 6K7, Detector 6Q7, and output 6F6.
:::
::::
::::::::From what you describe the audio output section is working. The problem would seem to be one stage back in the detector AF section. If you touch the input grid of the detector grid you should get a loud buzz from the speaker. If not trouble shoot the AF amp.
:::::::
:::::::
:::::::Hmmmm....not so sure. Have you checked the cathode? With 320 Volts on both sides of the output transformer, the output might not be drawing current. (there should be a SMALL drop across the primary of the transformer) I haven't seen the schematic, but if there is a cathode resistor, there might be an open in that circuit.
:::::::Lewis
::::::::
:::::::
:::::::
::::::
::::::
:::::Thanks for your input, Cathode goes straight to ground. Have very carefully checked with ohms meter all speaker plug connections, and everythings okay. I agree with Lewis, The output transformer does not appear to load up and therefore no current. Maybe the primary is shorted out, but if so, why do I read 600 ohms through it? The speaker assembly is from the original chassis that had been hit by lightning.
:::::Gerry
:::::
::::
::::
:::
:::
::
::
:
:

:Gerry,
:
:Probably too obvious but are you using a 6F6 G/GT (glass) or 6F6 (metal) tube? One could see the filament working in a glass tube, but not a metal one. If using a metal tube, does it get warm. If not, there may be a problem with one of the socket filament contacts 2 or 7.
:
:If the tube has B+ voltage on the plate, screen grid and minus bias on the control grid, and with a subbed in OPT and the filament is lighted, there should be some kind of sound out of the OPT.
:
:Clifton
Thanks for your input everyone, the problem is now solved. I was putting some tubes away in my tube vault, and noticed a brand new 6F6 metal tube. I put that in the chassis, and heard a pop on the loudspeaker, and the radio came to life. Then changed back to the 6F6GT that I previously had in, and it continued to play. giggled all pins on the 6F6 and speaker plug connector, and could not re-create the problem. So not sure if the 6F6 was not conducting, and had a pin problem, or the output transformer was not loading up therefore no current over it. When the 6F6 was not conducting, had close to 330 volts over both sides of the primary transformer, after the tube started conducting had 240 on one side of the primary and 230 on the other with -7 on the grid of the 6F6. Thank you everyone for your help.
Gerry
:
:::Gerry,
:::
:::Not sure if I under stand your statement that you put a single-ended OPT across the B+. The transformer should be connected one end of the OPT primary to pin 3 of the 6F6 socket and the other end to B+.
:::
:::Clifton
:::Thanks Clifton, Your right, the OPT was hooked up properly off the plate of the 6F6 and the other side to the positive side of the electrolytics and screen gride of 6F6.
::Gerry
:::::Believe it was mentioned the radio used a 6F6 tube as audio output. Tried a new tube? Has the screen grid voltage on pin 4 been checked. There was mention that the cathode was grounded. Does the control grid pin 5 have the proper minus bias voltage?
:::::
:::::Clifton
::::
:::::Hi, Thanks for your reply, Yes I have tried a new tube, also have checked the continuety between all the pins of the output tube 6F6, and they all check out okay, Have also checked out the speaker plug pins, and all check out okay. Today, I took the speaker plug terminal on the chassis out, and tied a 2000 Ohms resistor across the field coil output pins and put a new single ended output transformer across the B Plus, and tied a bench test speaker to the output. I still had the same results, no current through the 6F6 output tube. Yes, I have tried to lower the Bias resistance on the grid, and it does not seem to make a difference. The screen grid output is the same level as the plate on the output tube voltage. When I had the jury rig output transformer and speaker hooked up today, I used my Heathkit IT-12 Signal Tracer, set to Audio output on the plate of the Detector plate, and touched the grids of the IF tube 6K7, and lost the BC station that was tuned into on the AM Band. This chassis is a Canadian Majestic model "Rodney" "Renown" and "Hood", also included in this chassis lineup are Rogers and DeForest models, the model numbers are 6 ("M" "R" or "D") then 632 respectitely. The best source for Older Canadian Chassis schematic's are from webb site "www.pacifictv.ca". Thank you for your help.
::::One thing that you have to keep in mind, is the tube numbers. The schematic on the Pacific TV site is a re-draw from the original, and the original schematic shows the tube identies as "Rogers Tubes", which are different than the normal group we are used to dealing with. The tube line up in Rogers tubes reads:
::::Rectifier, 80. RF amplifier 6K7, Mixer 6A7, IF Amplifier 6K7, Detector 75, and Output 6F6: in What we are normally used to, converts to: Detector 80, RF amplifier 6K7, Mixer 6A8, IF amplifier 6K7, Detector 6Q7, and output 6F6.
::::
:::::
:::::::::From what you describe the audio output section is working. The problem would seem to be one stage back in the detector AF section. If you touch the input grid of the detector grid you should get a loud buzz from the speaker. If not trouble shoot the AF amp.
::::::::
::::::::
::::::::Hmmmm....not so sure. Have you checked the cathode? With 320 Volts on both sides of the output transformer, the output might not be drawing current. (there should be a SMALL drop across the primary of the transformer) I haven't seen the schematic, but if there is a cathode resistor, there might be an open in that circuit.
::::::::Lewis
:::::::::
::::::::
::::::::
:::::::
:::::::
::::::Thanks for your input, Cathode goes straight to ground. Have very carefully checked with ohms meter all speaker plug connections, and everythings okay. I agree with Lewis, The output transformer does not appear to load up and therefore no current. Maybe the primary is shorted out, but if so, why do I read 600 ohms through it? The speaker assembly is from the original chassis that had been hit by lightning.
::::::Gerry
::::::
:::::
:::::
::::
::::
:::
:::
::
::
:
:

Might be informative to use an "audio signal injector" to exonerate (or indict) the audio output stage since that seems to indeterminate at this point. I use an old (OLD!) pocket transistor radio with the speaker terminals connected to a couple of long 22 ga. wires with alligator clips on them, and a 0.1 uf cap in series with one of the clips. Connect one clip to the radio chassis and the other to the grid of the 1st audio (or the wiper of the volume control), turn the transistor radio/audio source on, and see if the set "plays through".

:Might be informative to use an "audio signal injector" to exonerate (or indict) the audio output stage since that seems to indeterminate at this point. I use an old (OLD!) pocket transistor radio with the speaker terminals connected to a couple of long 22 ga. wires with alligator clips on them, and a 0.1 uf cap in series with one of the clips. Connect one clip to the radio chassis and the other to the grid of the 1st audio (or the wiper of the volume control), turn the transistor radio/audio source on, and see if the set "plays through".
:Thank you, I will try that.
Gerry

:Might be informative to use an "audio signal injector" to exonerate (or indict) the audio output stage since that seems to indeterminate at this point. I use an old (OLD!) pocket transistor radio with the speaker terminals connected to a couple of long 22 ga. wires with alligator clips on them, and a 0.1 uf cap in series with one of the clips. Connect one clip to the radio chassis and the other to the grid of the 1st audio (or the wiper of the volume control), turn the transistor radio/audio source on, and see if the set "plays through". \

Thank you everyone, problem solved. I previously had changed out the 6F6 tube, with a new one (GT type), and that did not seem to make a difference, still no current at the 6F6. Today I found a new 6F6 metal in my stock put that in, and the output stage now works. Changed back to the 6F6 GT, and still working. pushed and pried around all 6F6 pins, and could not re-create problem. Before trying to fire it up, I had carfully cleaned all the switch positions and socket pins. I dont know what the problem was.
Gerry
:

::Might be informative to use an "audio signal injector" to exonerate (or indict) the audio output stage since that seems to indeterminate at this point. I use an old (OLD!) pocket transistor radio with the speaker terminals connected to a couple of long 22 ga. wires with alligator clips on them, and a 0.1 uf cap in series with one of the clips. Connect one clip to the radio chassis and the other to the grid of the 1st audio (or the wiper of the volume control), turn the transistor radio/audio source on, and see if the set "plays through". \
:
:Thank you everyone, problem solved. I previously had changed out the 6F6 tube, with a new one (GT type), and that did not seem to make a difference, still no current at the 6F6. Today I found a new 6F6 metal in my stock put that in, and the output stage now works. Changed back to the 6F6 GT, and still working. pushed and pried around all 6F6 pins, and could not re-create problem. Before trying to fire it up, I had carfully cleaned all the switch positions and socket pins. I dont know what the problem was.
:Gerry
::
:
:
Gerry, a possible reason for temporary trouble there is a poor ground connection at the tube socket, or a cold solder joint to one of the pins of the socket. Swapping tubes may have improved the situation, but if trouble returns, try resoldering in that area.

:::Might be informative to use an "audio signal injector" to exonerate (or indict) the audio output stage since that seems to indeterminate at this point. I use an old (OLD!) pocket transistor radio with the speaker terminals connected to a couple of long 22 ga. wires with alligator clips on them, and a 0.1 uf cap in series with one of the clips. Connect one clip to the radio chassis and the other to the grid of the 1st audio (or the wiper of the volume control), turn the transistor radio/audio source on, and see if the set "plays through". \
::
::Thank you everyone, problem solved. I previously had changed out the 6F6 tube, with a new one (GT type), and that did not seem to make a difference, still no current at the 6F6. Today I found a new 6F6 metal in my stock put that in, and the output stage now works. Changed back to the 6F6 GT, and still working. pushed and pried around all 6F6 pins, and could not re-create problem. Before trying to fire it up, I had carfully cleaned all the switch positions and socket pins. I dont know what the problem was.
::Gerry
:::
::
::
:Gerry, a possible reason for temporary trouble there is a poor ground connection at the tube socket, or a cold solder joint to one of the pins of the socket. Swapping tubes may have improved the situation, but if trouble returns, try resoldering in that area.
:
Thank you very much, I thought of that, and went and reheated most the joints on the 6F6 before coming to the forum. But I did not reheat the solder connection from the cathode to ground. It was still original and had not been touched. Will check that one if problem returns.
Gerry

::::Might be informative to use an "audio signal injector" to exonerate (or indict) the audio output stage since that seems to indeterminate at this point. I use an old (OLD!) pocket transistor radio with the speaker terminals connected to a couple of long 22 ga. wires with alligator clips on them, and a 0.1 uf cap in series with one of the clips. Connect one clip to the radio chassis and the other to the grid of the 1st audio (or the wiper of the volume control), turn the transistor radio/audio source on, and see if the set "plays through". \
:::
:::Thank you everyone, problem solved. I previously had changed out the 6F6 tube, with a new one (GT type), and that did not seem to make a difference, still no current at the 6F6. Today I found a new 6F6 metal in my stock put that in, and the output stage now works. Changed back to the 6F6 GT, and still working. pushed and pried around all 6F6 pins, and could not re-create problem. Before trying to fire it up, I had carfully cleaned all the switch positions and socket pins. I dont know what the problem was.
:::Gerry
::::
:::
:::
::Gerry, a possible reason for temporary trouble there is a poor ground connection at the tube socket, or a cold solder joint to one of the pins of the socket. Swapping tubes may have improved the situation, but if trouble returns, try resoldering in that area.
::
:Thank you very much, I thought of that, and went and reheated most the joints on the 6F6 before coming to the forum. But I did not reheat the solder connection from the cathode to ground. It was still original and had not been touched. Will check that one if problem returns.
:Gerry
:
AND if you're going to use that 6F6GT - maybe it would be a good idea to reflow the solder inside pins 2 and 7 just in case - as well as the socket connections.
Eddie

:::::Might be informative to use an "audio signal injector" to exonerate (or indict) the audio output stage since that seems to indeterminate at this point. I use an old (OLD!) pocket transistor radio with the speaker terminals connected to a couple of long 22 ga. wires with alligator clips on them, and a 0.1 uf cap in series with one of the clips. Connect one clip to the radio chassis and the other to the grid of the 1st audio (or the wiper of the volume control), turn the transistor radio/audio source on, and see if the set "plays through". \
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::::Thank you everyone, problem solved. I previously had changed out the 6F6 tube, with a new one (GT type), and that did not seem to make a difference, still no current at the 6F6. Today I found a new 6F6 metal in my stock put that in, and the output stage now works. Changed back to the 6F6 GT, and still working. pushed and pried around all 6F6 pins, and could not re-create problem. Before trying to fire it up, I had carfully cleaned all the switch positions and socket pins. I dont know what the problem was.
::::Gerry
:::::
::::
::::
:::Gerry, a possible reason for temporary trouble there is a poor ground connection at the tube socket, or a cold solder joint to one of the pins of the socket. Swapping tubes may have improved the situation, but if trouble returns, try resoldering in that area.
:::
::Thank you very much, I thought of that, and went and reheated most the joints on the 6F6 before coming to the forum. But I did not reheat the solder connection from the cathode to ground. It was still original and had not been touched. Will check that one if problem returns.
::Gerry
::
:AND if you're going to use that 6F6GT - maybe it would be a good idea to reflow the solder inside pins 2 and 7 just in case - as well as the socket connections.
:Eddie
:
Thanks Eddie:
Still using the 6F6GT, and so far everything okay. If problem re-occures will follow your advise, thank you.
Gerry