There is at least one cap from B+ to ground. Has it and other caps been replaced? Very leaky caps will short out B+ voltage.
http://www.nostalgiaair.org/PagesByModel/931/M0024931.pdf
Norm
:Hello
:I am still working on the Zenith 5F134. I have re-capped it, and re-tubed it. I bought the battery eliminator kit from Antique Electronic supply. I have re-wired the battery cable. When I connect it to the B-E, I have 2.2 volts A, 4.5 volts C, but my B voltage drops to about 4.3 volts instead of 135 volts. I can unplug the speaker, and the B voltage will go back up. I have ohm-ed the speaker, and do not have a short. Any ideas? Thanks
:Hi John
:
: There is at least one cap from B+ to ground. Has it and other caps been replaced? Very leaky caps will short out B+ voltage.
:
:http://www.nostalgiaair.org/PagesByModel/931/M0024931.pdf
:
:Norm
:
::Hello
::I am still working on the Zenith 5F134. I have re-capped it, and re-tubed it. I bought the battery eliminator kit from Antique Electronic supply. I have re-wired the battery cable. When I connect it to the B-E, I have 2.2 volts A, 4.5 volts C, but my B voltage drops to about 4.3 volts instead of 135 volts. I can unplug the speaker, and the B voltage will go back up. I have ohm-ed the speaker, and do not have a short. Any ideas? Thanks
There are two caps from plates of your 1J6 to ground. Either of these shorted will cause the speaker to make a pop and load voltage.
Norm
::Hi Norm
::
:: I have replaced all caps, but one might be bad. What is funny, is that the voltage is fine until I plug the speaker in. It makes a popping sound out of the speaker, then nothing. The output transformer does not show a short. I will try replacing the caps on the B+ and see what happens. Thanks Norm.
:
::Hi John
::
:: There is at least one cap from B+ to ground. Has it and other caps been replaced? Very leaky caps will short out B+ voltage.
::
::http://www.nostalgiaair.org/PagesByModel/931/M0024931.pdf
::
::Norm
::
:::Hello
:::I am still working on the Zenith 5F134. I have re-capped it, and re-tubed it. I bought the battery eliminator kit from Antique Electronic supply. I have re-wired the battery cable. When I connect it to the B-E, I have 2.2 volts A, 4.5 volts C, but my B voltage drops to about 4.3 volts instead of 135 volts. I can unplug the speaker, and the B voltage will go back up. I have ohm-ed the speaker, and do not have a short. Any ideas? Thanks
It's hard to see these tubes light. With the tubes out of the radio check resistance between pins #2 and #7. These are filament pins.
In your radio measure voltage between pins #2 and #7. Should have around 2 volts. If tubes have continuity & voltage is there, should be ok.
Norm
:Hi Norm,
:OK, you were right. One of the .002 caps was shorted. Now, I have good voltage on B+. The 1C7, 1J6, and the 1H4 light up. The 1D5 and 1F7 does not. Should they? I am not getting anything, no static, no nothing. All voltages look close. I don't know if one or both of the tubes are bad. Thanks
:John
::
::
::Hi John
::
:: There are two caps from plates of your 1J6 to ground. Either of these shorted will cause the speaker to make a pop and load voltage.
::
::Norm
::
::
::
::
::::Hi Norm
::::
:::: I have replaced all caps, but one might be bad. What is funny, is that the voltage is fine until I plug the speaker in. It makes a popping sound out of the speaker, then nothing. The output transformer does not show a short. I will try replacing the caps on the B+ and see what happens. Thanks Norm.
:::
::::Hi John
::::
:::: There is at least one cap from B+ to ground. Has it and other caps been replaced? Very leaky caps will short out B+ voltage.
::::
::::http://www.nostalgiaair.org/PagesByModel/931/M0024931.pdf
::::
::::Norm
::::
:::::Hello
:::::I am still working on the Zenith 5F134. I have re-capped it, and re-tubed it. I bought the battery eliminator kit from Antique Electronic supply. I have re-wired the battery cable. When I connect it to the B-E, I have 2.2 volts A, 4.5 volts C, but my B voltage drops to about 4.3 volts instead of 135 volts. I can unplug the speaker, and the B voltage will go back up. I have ohm-ed the speaker, and do not have a short. Any ideas? Thanks
:Hi John
:
: It's hard to see these tubes light. With the tubes out of the radio check resistance between pins #2 and #7. These are filament pins.
:
: In your radio measure voltage between pins #2 and #7. Should have around 2 volts. If tubes have continuity & voltage is there, should be ok.
:
: Norm
:
::Hi Norm,
::OK, you were right. One of the .002 caps was shorted. Now, I have good voltage on B+. The 1C7, 1J6, and the 1H4 light up. The 1D5 and 1F7 does not. Should they? I am not getting anything, no static, no nothing. All voltages look close. I don't know if one or both of the tubes are bad. Thanks
::John
:::
:::
:::Hi John
:::
::: There are two caps from plates of your 1J6 to ground. Either of these shorted will cause the speaker to make a pop and load voltage.
:::
:::Norm
:::
:::
:::
:::
:::::Hi Norm
:::::
::::: I have replaced all caps, but one might be bad. What is funny, is that the voltage is fine until I plug the speaker in. It makes a popping sound out of the speaker, then nothing. The output transformer does not show a short. I will try replacing the caps on the B+ and see what happens. Thanks Norm.
::::
:::::Hi John
:::::
::::: There is at least one cap from B+ to ground. Has it and other caps been replaced? Very leaky caps will short out B+ voltage.
:::::
:::::http://www.nostalgiaair.org/PagesByModel/931/M0024931.pdf
:::::
:::::Norm
:::::
::::::Hello
::::::I am still working on the Zenith 5F134. I have re-capped it, and re-tubed it. I bought the battery eliminator kit from Antique Electronic supply. I have re-wired the battery cable. When I connect it to the B-E, I have 2.2 volts A, 4.5 volts C, but my B voltage drops to about 4.3 volts instead of 135 volts. I can unplug the speaker, and the B voltage will go back up. I have ohm-ed the speaker, and do not have a short. Any ideas? Thanks
Higher voltage on pin #3 of your 1F7 is due to using a modern meter. You should find pin #6 also reads higher. Modern meters don't load down the circuit as much.
Touching top cap on your 1F7 should cause loud hum.
Pin #4 & #5 are input grids on the 1J6. Wouldn't expect these pins to be positive. Follow the schematic through your audio input transformer connected to the grids. Voltage should come from your power supply. Check continuity of the audio interstage transformer.
http://www.nostalgiaair.org/PagesByModel/931/M0024931.pdf
Norm
::Well, one other thing. The voltage on pin 4 and 5 on the 1J6 shows to be -1. I have 3.74 volts on each pin. Could this also be a problem, and, if so, how do I correct the voltage. Thanks
::
::
::
:::Sorry, the 24 volts is on pin 3 of the 1F7 tube. It shows to have 75 volts, instead of 24.
:::
:::
::::Ok, pins 2 and 7 on the 1D5, and 1F7 show continuity,and I have 2 volts at both tubes. I took a signal generator and have tone in the speaker from the 1J6 (power tube), and 1H4 (driver tube). I do not have tone from 1F7 back. I do have voltage, and everything is close except on the 1C7. Pin #3 (plate) has 74 volts and the schematic shows it is suppose to be 24 volts. Would this be the problem? All over voltages look to be close. I am lost from this point. Thanks
:::
::::Hi John
::::
:::: It's hard to see these tubes light. With the tubes out of the radio check resistance between pins #2 and #7. These are filament pins.
::::
:::: In your radio measure voltage between pins #2 and #7. Should have around 2 volts. If tubes have continuity & voltage is there, should be ok.
::::
:::: Norm
::::
:::::Hi Norm,
:::::OK, you were right. One of the .002 caps was shorted. Now, I have good voltage on B+. The 1C7, 1J6, and the 1H4 light up. The 1D5 and 1F7 does not. Should they? I am not getting anything, no static, no nothing. All voltages look close. I don't know if one or both of the tubes are bad. Thanks
:::::John
::::::
::::::
::::::Hi John
::::::
:::::: There are two caps from plates of your 1J6 to ground. Either of these shorted will cause the speaker to make a pop and load voltage.
::::::
::::::Norm
::::::
::::::
::::::
::::::
::::::::Hi Norm
::::::::
:::::::: I have replaced all caps, but one might be bad. What is funny, is that the voltage is fine until I plug the speaker in. It makes a popping sound out of the speaker, then nothing. The output transformer does not show a short. I will try replacing the caps on the B+ and see what happens. Thanks Norm.
:::::::
::::::::Hi John
::::::::
:::::::: There is at least one cap from B+ to ground. Has it and other caps been replaced? Very leaky caps will short out B+ voltage.
::::::::
::::::::http://www.nostalgiaair.org/PagesByModel/931/M0024931.pdf
::::::::
::::::::Norm
::::::::
:::::::::Hello
:::::::::I am still working on the Zenith 5F134. I have re-capped it, and re-tubed it. I bought the battery eliminator kit from Antique Electronic supply. I have re-wired the battery cable. When I connect it to the B-E, I have 2.2 volts A, 4.5 volts C, but my B voltage drops to about 4.3 volts instead of 135 volts. I can unplug the speaker, and the B voltage will go back up. I have ohm-ed the speaker, and do not have a short. Any ideas? Thanks
Thomas
Pins #4 & #5 on your 1J6 would have an audio interstage transformer. A reading in megs shows the transformer is open. Normal reading would be around 1K.
You can replace it with Stancor A-53C. AES, www.tubesandmore.com and Radio Daze, www.radiodaze.com both have similar transformers. Might also check PTOP, www.oldradioparts.com . Sometimes they have original parts. Do not order A-53 from PTOP. It doesn't have the center tap needed for your radio.
C voltages should be negative going to a tube grid.
Norm
:Norm and Tom;
:On the schematic, page 2, the tube position diagram shows a filter choke. The schematic shows this to be the audio transformer, (#6 on legend). On one side of this choke-transformer, I had to re-solder the small wires to the leads. I get a very high resistance (over 3 meg. On the other side of the choke-transformer, the voltage is the C+ voltage, (+4.5). These wires go to pin 4 & 5 on the 1J6. These should be -1. Should I change the polarity of my C voltage? And, does this resistance sound right for this choke-transformer?
::
::
::See to it, too, that the tube is not weak, as a weak tube will not load down the resistor that feeds B+ properly, which will cause the voltage to be much higher. However, as Norm said, the meter suggested in the schematic will load down the circuit much more. 1000 ohms per volt is an incredible load for radio work. 20,000 ohms per volt is better, and a vacuum tube volt meter is ideal.
::
::Thomas