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Old 03-04-2019, 09:49 PM
Phil Phil is offline
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Join Date: Aug 2016
Posts: 132
It was one of my first thoughts there was a change during production but haven't been able to find any other schematics. The riders lists a few changes in parts, whereas the Sam's doesn't, but not the resistor in the vertical osc. section. I have found a few mistakes in the Sam's. For one thing according to the Sam's tube placement chart the audio input tube is a 6AU6, whereas it is actually a 6AV6, a very different tube. Also the way the vertical osc. is wired according to the Sam's will not work. The riders again is correct. I found a well hidden 56k that measured 80k replacing it helped the vertical linearity a good deal. Now I'm trying to determine why I have no audio. Feeding a signal into the input of the sound IF gives an appropriate output so the sound carrier must be lost between the tuner and first two IF stages. The cores in the upper section of the unshielded IF transformers are ruined. Apparently they were stuck and the previous person who butchered this thing so much anlso broke them and made the top of the three of them perfectly flat. I will try replacing these from my parts chassis tommorow and see if I can get any hint of sound carrier through it then.
The vertical linearity is still not great. I will try a few other 6K6 tubes and see if any if them do better.
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