I found this one in the dump a couple years back and have replaced all the capacitors and resistors. I also bought some new tubes for it including two brand new 6L6G's. I installed a RCA jack crossing two contacts on the volume control so I can listen to my iPod on it. When I first turn it on it sounds great for ten minutes or so, then the sound quality begins to degrade and sound grainy. Just wondering if anyone has any ideas? I'm semi new to this so please go easy on the tech talk! Thanks! Kyal.

:I found this one in the dump a couple years back and have replaced all the capacitors and resistors. I also bought some new tubes for it including two brand new 6L6G's. I installed a RCA jack crossing two contacts on the volume control so I can listen to my iPod on it. When I first turn it on it sounds great for ten minutes or so, then the sound quality begins to degrade and sound grainy. Just wondering if anyone has any ideas? I'm semi new to this so please go easy on the tech talk! Thanks! Kyal.
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I am not a genius...but why at the volume control? I would have went for splitting the speaker circuit...that is usually how it is done...Maybe you are interupting the rest of the circuit..seriously..You are cutting into the gain..

::I found this one in the dump a couple years back and have replaced all the capacitors and resistors. I also bought some new tubes for it including two brand new 6L6G's. I installed a RCA jack crossing two contacts on the volume control so I can listen to my iPod on it. When I first turn it on it sounds great for ten minutes or so, then the sound quality begins to degrade and sound grainy. Just wondering if anyone has any ideas? I'm semi new to this so please go easy on the tech talk! Thanks! Kyal.
I didn't do it at the vol control for any other reason than I got sound playing out the speaker when I did it. Lol. As I said I'm new to this and sometimes experimental. What do you mean hook it up to the speaker circuit? Like at the tube inputs into the transformer? Thanks for your help Cindy!

:I am not a genius...but why at the volume control? I would have went for splitting the speaker circuit...that is usually how it is done...Maybe you are interupting the rest of the circuit..seriously..You are cutting into the gain..
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:::I found this one in the dump a couple years back and have replaced all the capacitors and resistors. I also bought some new tubes for it including two brand new 6L6G's. I installed a RCA jack crossing two contacts on the volume control so I can listen to my iPod on it. When I first turn it on it sounds great for ten minutes or so, then the sound quality begins to degrade and sound grainy. Just wondering if anyone has any ideas? I'm semi new to this so please go easy on the tech talk! Thanks! Kyal. Sorry, actually didn't cross vol control on this one. I have seven different radios I'm working on and had done that on a couple of them. This one the iPod plugs directly into the tv input jack. So I don't know if it's a tube that sounds bad when it warms up or what? Thanks.
:I didn't do it at the vol control for any other reason than I got sound playing out the speaker when I did it. Lol. As I said I'm new to this and sometimes experimental. What do you mean hook it up to the speaker circuit? Like at the tube inputs into the transformer? Thanks for your help Cindy!
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::I am not a genius...but why at the volume control? I would have went for splitting the speaker circuit...that is usually how it is done...Maybe you are interupting the rest of the circuit..seriously..You are cutting into the gain..
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::::I found this one in the dump a couple years back and have replaced all the capacitors and resistors. I also bought some new tubes for it including two brand new 6L6G's. I installed a RCA jack crossing two contacts on the volume control so I can listen to my iPod on it. When I first turn it on it sounds great for ten minutes or so, then the sound quality begins to degrade and sound grainy. Just wondering if anyone has any ideas? I'm semi new to this so please go easy on the tech talk! Thanks! Kyal. Sorry, actually didn't cross vol control on this one. I have seven different radios I'm working on and had done that on a couple of them. This one the iPod plugs directly into the tv input jack. So I don't know if it's a tube that sounds bad when it warms up or what? Thanks.
::I didn't do it at the vol control for any other reason than I got sound playing out the speaker when I did it. Lol. As I said I'm new to this and sometimes experimental. What do you mean hook it up to the speaker circuit? Like at the tube inputs into the transformer? Thanks for your help Cindy!
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:::I am not a genius...but why at the volume control? I would have went for splitting the speaker circuit...that is usually how it is done...Maybe you are interupting the rest of the circuit..seriously..You are cutting into the gain..
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Sorry about that, I was thinking of interrupting the speaker..to add another audio source. eg; headphones. Therefore would cut out the speaker all together..If your audio starts to fade after several minutes.....I would be looking for a resistor overheating, especially the larger wattage one on the power supply end, next to the electrolytics.
A capacitor leaking, or a weak tube in the audio portion of the radio, could be the issue. Depending on the usage of the term, "Grainy", it could be in the mixing stage of the radio. Check the voltages at the different stages of audio gain, these should be listed on the schematic, which most are available on this site.
Unfortunately could be several possibilities at this point. Volume control could even be bad, I have had them fade out when they start to wear out. Look for the obvious first..Overheating, tubes running too hot too fast. New tubes are not always good. It takes the current draw of the radio to pull them down to their breaking point...sometimes like the radios do me. ;p..sorry I couldn't help more. But list a model number so someone who has more experience may be able to help. Good luck. Hope I helped out some.

:::::I found this one in the dump a couple years back and have replaced all the capacitors and resistors. I also bought some new tubes for it including two brand new 6L6G's. I installed a RCA jack crossing two contacts on the volume control so I can listen to my iPod on it. When I first turn it on it sounds great for ten minutes or so, then the sound quality begins to degrade and sound grainy. Just wondering if anyone has any ideas? I'm semi new to this so please go easy on the tech talk! Thanks! Kyal. Sorry, actually didn't cross vol control on this one. I have seven different radios I'm working on and had done that on a couple of them. This one the iPod plugs directly into the tv input jack. So I don't know if it's a tube that sounds bad when it warms up or what? Thanks.
:::I didn't do it at the vol control for any other reason than I got sound playing out the speaker when I did it. Lol. As I said I'm new to this and sometimes experimental. What do you mean hook it up to the speaker circuit? Like at the tube inputs into the transformer? Thanks for your help Cindy!
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::::I am not a genius...but why at the volume control? I would have went for splitting the speaker circuit...that is usually how it is done...Maybe you are interupting the rest of the circuit..seriously..You are cutting into the gain..
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:Sorry about that, I was thinking of interrupting the speaker..to add another audio source. eg; headphones. Therefore would cut out the speaker all together..If your audio starts to fade after several minutes.....I would be looking for a resistor overheating, especially the larger wattage one on the power supply end, next to the electrolytics.
: A capacitor leaking, or a weak tube in the audio portion of the radio, could be the issue. Depending on the usage of the term, "Grainy", it could be in the mixing stage of the radio. Check the voltages at the different stages of audio gain, these should be listed on the schematic, which most are available on this site.
: Unfortunately could be several possibilities at this point. Volume control could even be bad, I have had them fade out when they start to wear out. Look for the obvious first..Overheating, tubes running too hot too fast. New tubes are not always good. It takes the current draw of the radio to pull them down to their breaking point...sometimes like the radios do me. ;p..sorry I couldn't help more. But list a model number so someone who has more experience may be able to help. Good luck. Hope I helped out some.
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It ended up being the primary power transformer...I noticed it was getting hot so I tested the voltage readings and they were all way off...have to get it re wound..!