EJP; I would say that the cathode resistor is telling you the truth - V2 is turned on significantly with high current conduction being the result. I do not have a schematic for the 350A, but for a

I'm fixing a 350A and I have a mystery at V2, the 2nd IF amplifier (6AU6). Unit is showing poor limiting and I think low gain, certainly rather low sensitivity. I think I've tracked this down to V2.

Those are excellent suggestions, Herb--thanks! I have worked with this engineer in the past, when the signal from our local frequency tower suddenly started sounding like a bad digital phone call.

Could be, if something in the HD transmission changed...but I'm not sure why that would have happened all of a sudden. But I'll pass the suggestion along--thanks!

Kevin, I have had conversations with a local station engineer due to a related experience. In my case the audio improved significantly. I first spoke to the station manager and then their engineer.

Maybe HD noise ?

I hope this question isn't too off-topic, but I know there are many station engineers in the group, and I'm very perplexed by the suddenly disastrous signal from my favorite local classical station.

Mike , I quite agree with Bob’s comments about test equipment. There are so many choices and sometimes a inappropriate purchase can lead to lots of disappointment and frustration . This hobby is

Thank you Bob (and Joe, Herb, EJP). I think I have it sorted out now (at least for this model's tuner). I tried the AGC line for Y, but was not happy with the results. I tried the output side of

Thanks for the tip about the discussion of sweepers on antiqueradios.com Bob. Very useful. Sounds like used HP is the way to go. -- Mike Miller PA, USA

see this thread - these guys have lots of collective experience with sweepers, captured in this discussion https://antiqueradios.com/forums/viewtopic.php?t=143716 My take on test gear is buy quality,

I see there are folks selling the DA-F76 service manual, but agree, there is not much info on it otherwise. If you want to open it up and take some detailed, pictures, it could add to the discussion.

Yep, now you got it - these look good. Don't worry about the exact IF frequency here - nowhere is it written in stone that it has to be exactly 10.700 MHz. Unlike digital tuners with a crystal time

I understand the importance of that fine adjustment and I don't give up in searching a reliable technician. It wars twice because, if I'll find, I shall adjust also the Fisher MPX 100 that accompany

Thanks EJP. I got the IF sweep working. I input the signal at the input of the IF board (the base of the first amp stage Q 301). I probed Y at the input to the limiter, the base of the first limiter

Or might be Mitsubishi DA-F76 I have recently purchased at a good price this tuner on ebay. I cannot find an owners manual or any documentation regarding this tuner. It works fine, i have figured

Victor, The T-100 uses the Motorola mc1310 decoder as i recall. The Accuphase implementation of this very common MPX decoder IC is very well done. Past experience has shown that the typical T-100

Hi Herb, Nice explanation, a real lesson for me. Unfortunately, there is no one around me to have the gear and knowledge to make the alignment of the decoder. For the beginning, I shall change the

Any of you fine fellas have any experience with the Wavetek 193 sweep generator? I see one or two on eBay. Or any suggestions for comparable units of low used cost? As I very seldom encounter tunable

Hi Victor, A few comments having modded many tuners for Ed Hanlon and many customers of my own by virtue of owning two hi end audio shops in CT. Tantalums were frequently chosen by designers in the