I have changed the paper caps and the three stage lytic on this Arvin 544A [http://www.nostalgiaair.org/PagesByModel/548/M0012548.pdf]. I checked all resistors and replaced one that was out of tolerance. I've taken multiple voltage readings and each time readings are satisfactory.

I have changed out the tubes 3 times still NO AUDIO. I do have sound from the speaker so I am confident that is not the problem.

Any suggestions as to what might be wrong would be appreciated.

I have changed the paper caps and the three stage lytic on this Arvin 544A [http://www.nostalgiaair.org/PagesByModel/548/M0012548.pdf]. I checked all resistors and replaced one that was out of tolerance. I've taken multiple voltage readings and each time readings are satisfactory.

I have changed out the tubes 3 times still NO AUDIO. I do have sound from the speaker so I am confident that is not the problem.

Any suggestions as to what might be wrong would be appreciated.
I have changed the paper caps and the three stage lytic on this Arvin 544A http://www.nostalgiaair.org/PagesByModel/548/M0012548.pdf. I checked all resistors and replaced one that was out of tolerance. I've taken multiple voltage readings and each time readings are satisfactory.

I have changed out the tubes 3 times still NO AUDIO. I do have sound from the speaker so I am confident that is not the problem.

Any suggestions as to what might be wrong would be appreciated.

Hi

Do you hear hum touching center terminal on the volume control? If so audio circuits are good, 12SQ7 & 50L6.

http://www.nostalgiaair.org/PagesByMode ... 012548.pdf

Is pin #5 on your 12SA7 several volts negative. You mention measuring other voltages but this one is there only when the oscillator operates.

Yes, I do have minus voltage on pin 5/SA7 / -5.17v and, yes again, I get a hum on the center wiper of volume control.

Positive signs, right?

Hi

You are almost there. Pin #6 and #8 on 12SK7 needs to have positive voltage. On a 12SA7 it will be pins #3 and #4. In most cases it you have these voltages the radio should receive some stations. Hopefully no one tightened those IF can screws....

Hi,

Pin 6 & 8 / SK7 - 97v-96v respectively
Pin 3 & 4 / SA7 - 94v-97v respectively

Is there a way to tell if the can screws are too tight?

Hi

Voltages are good. Tightening screws is more of a joke. Someone not knowing may tighten IF can adjustment screws. They shouldn't be touched until a radio is ready to align.

Any chance a replacement component was attached to the wrong pin? I would look around 12SA7 and 12SK7 tubes. 50L6, 12SQ7 and 35Z5 circuits are operating.

Nothing extra should be attached to pin #3 and #8 of 12SA7 or #4 and #8 of 12SK7.

Are tuner plates shorting?

I do not see anything in what I have replaced that would be causing the lack of audio.

Tubes SA7 and SK7 are without change. Here is a picture of under the chassis (I realize now that I don't know how to insert an img you gotta have a url addr?)...if I have any concern it's that collection of caps (2 - .047s) and resistor (330k) at pin 6 of the 50L6.

Another thing and although you can't see it in this picture I had a connection point under chassis on pin 4 of the 35z5 break and I have resoldered it. It appears to be good and sturdy.

Any ideas? Sorry 'bout the picture.

Pin #4 on 35Z5 must have been used as a tie point? Two or more wires connected together on this pin. It has no internal connection on a 35Z5.

Try connecting a long piece of wire (several feet) to pin #8 of 12SA7. It will act as an antenna and might pick up something.

50L6 area should be ok but again Pin #6 is used as a tie point on this tube. Pin #6 has no internal connection.

I figured the pins were junction points and not relevant to what's goes on under the chassis per se.

I had no response when connectng a wire to pin 8 of the SK7. I can hear a faint subtle hum from the speaker, but it has no volume up, however, I can turn the faint hun down...then off. I will I get the same hum without connecting anything to pin 8.

I've been over my work 50x. the voltages are good. Could it be the speaker? I've not tested it or the transformer.

No the hum test on the volume control means the problem is to the "left" of the audio section. A signal generator would be really helpful here, as you can go backwards stage by stage until you locate the problem.