well, i shot myself in the foot today. i pulled a working fm/am/phono/amp from my grandmother's old console setup (trying to find out what make/model/etc at the moment in attempt to find a schematic). it was completely working when i pulled it and was hoping to remove the radio side to make it into just an amp/preamp. well, now it wont even power up. so i guess my new question is whats a simple amp setup that uses 2 35eh5 and a single 12ax7? ive got all the working transformers for it too, along with the stereoplex setup for it, just nothings powering on. i figured i would include a couple pics of the layout, maybe someone knows what kinda amp this is. thanks.
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looks like i'm outta luck then. was hoping maybe someone knew of a site about colsole radios or somethin. oh well. my fault for tearing through it.....
given that you have tubes with a 35 prefix this means that you have a heater string across the mains. I also see from the diagrams that there is a dropping resistor. The heaters are connected in series then through the dropping resistor straight across the mains power line.
If you have a mulitmeter, keeping the unit unplugged, check to see if you have continutity across the heater string.
also, clip one end of the multimeter to the live pin on the plug and trace the connection all the way through to the rectifier, dc will be generated using a half wave rectifier.
to identify the valves if you dont already know what they are, go to www.duncanamps.com and use his online TDSL tool to get the pin arrangements.
as you are getting nothhing at all, it is likely that there is a break in the power/heater cct somewhere.
hope that this helps.l
bill
If you have a mulitmeter, keeping the unit unplugged, check to see if you have continutity across the heater string.
also, clip one end of the multimeter to the live pin on the plug and trace the connection all the way through to the rectifier, dc will be generated using a half wave rectifier.
to identify the valves if you dont already know what they are, go to www.duncanamps.com and use his online TDSL tool to get the pin arrangements.
as you are getting nothhing at all, it is likely that there is a break in the power/heater cct somewhere.
hope that this helps.l
bill
...and i think you're right about the heater thing. i was trying to figure out why all the tubes were connected. i'll have to check on the power too. thanks very much.
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