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the middle input has no sound whatsoever. Both other inputs work fine. the shunts are all making and breaking contact when they are supposed to. I guess I could try blindly replacing the jack, but I'd like to prove a problem if I can...
And as for the bias voltage, my transformer doesn't have a bias tap so I pulled voltage from the HT and used a 220K dropping resistor. The transformers being used are from an old Hammond M3 organ amp and has a much higher HT voltage than what shows on the Harvard schematic. I've got 445 on the plates and a -41.6 bias voltage at pin 5. I'm thinking I need to maybe go to a 250K or even a little higher to get the bias voltage down a bit? The amp sounds great but squelches at 75% volume and up (and the squelching can be altered and/or initiated with a high tone level setting as well). I also noticed that the bias voltage went up to the -50's when the vol and tone were increased to the point of squelching. comments on that??
Except for the bias supply, salvaged transformers, and 6AV6 in V1, it's a straight stock copy of the original.
http://api.ning.com/files/iRhh93x186...Ct/HARVAR2.GIF
And as for the bias voltage, my transformer doesn't have a bias tap so I pulled voltage from the HT and used a 220K dropping resistor. The transformers being used are from an old Hammond M3 organ amp and has a much higher HT voltage than what shows on the Harvard schematic. I've got 445 on the plates and a -41.6 bias voltage at pin 5. I'm thinking I need to maybe go to a 250K or even a little higher to get the bias voltage down a bit? The amp sounds great but squelches at 75% volume and up (and the squelching can be altered and/or initiated with a high tone level setting as well). I also noticed that the bias voltage went up to the -50's when the vol and tone were increased to the point of squelching. comments on that??
Except for the bias supply, salvaged transformers, and 6AV6 in V1, it's a straight stock copy of the original.
http://api.ning.com/files/iRhh93x186...Ct/HARVAR2.GIF
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