Istari Posted January 21, 2009 Share Posted January 21, 2009 Good Evening! I have a H.H. Scott 222A that was rebuilt by NOS Valves a few years back and it worked well. I have it connected to a pair of Cornwalls ('79s) and was playing it very low last night and all seemed Ok. When I came down this morning to start work I turned on the unit and - No Sound!!! I took the cover off and saw that the filaments for tubes 1, 2, 6 & 7 (the 12AX7s) don't light up and C3 isn't warm. If I turn the volume up all of the way clockwise I can just hear Iris DeMent coming from both speakers. Any ideas from the experts as to where I should look? I have the bottom cover off. Yes, I have some experience and know to be careful of the lethal voltages lurking within.... Thanks! Quote Link to comment Share on other sites More sharing options...
Guest " " Posted January 22, 2009 Share Posted January 22, 2009 .. Quote Link to comment Share on other sites More sharing options...
Istari Posted January 22, 2009 Author Share Posted January 22, 2009 I have the 222A Sam's Photofact schematics and component layouts (8 pages I believe). It been a loooong time since I had to get into a schematic. I'm hoping I can get a bit of help as to where to look and what to replace. I have a very old scope and a couple of good fluke digital multimeters, a Weller soldering iron and lots of parts. This was brought up to working order by NOS Valves several years ago. I can't send it back for a going over as cash is tight now. The filaments to V1, 2, 6 & 7 don't light and C3 isn't warm, so it appears to be some where in that area, maybe.... Quote Link to comment Share on other sites More sharing options...
mark1101 Posted January 22, 2009 Share Posted January 22, 2009 Can you test the tubes? Check the rectifier. I would just try replacing the recifier. Quote Link to comment Share on other sites More sharing options...
Istari Posted January 22, 2009 Author Share Posted January 22, 2009 After I looked closed at the schematic, I realized all of the heaters were in series on the 12AX7s... had a bad tube. Unit is playing just fine now. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted January 22, 2009 Share Posted January 22, 2009 " I realized all of the heaters were in series on the 12AX7s..." congrats Quote Link to comment Share on other sites More sharing options...
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