need help with (now) not-working amp

SQ Kid · 13th April 2004, 10:15 PM

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.

SQ Kid · 13th April 2004, 10:16 PM

and the stereoplex section

SQ Kid · 16th April 2004, 01:13 AM

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.....

billr · 16th April 2004, 05:32 AM

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

SQ Kid · 16th April 2004, 05:13 PM

...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.

adamamp · 16th April 2004, 07:41 PM

Just a guess but double check the interconnect AC socket/plug sometimes after 50 years they do not like to get wiggled

Hope it works out so simple.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Amp non working	covik	Solid State	0	12th November 2006 09:12 PM
WTB Krell KSA Mk2- working or non working	Jozua	Swap Meet	0	20th March 2006 12:14 PM
sub amp not working	felzi	Chip Amps	0	28th July 2005 06:29 AM
p3a not working, help!	benmanf	Solid State	9	27th May 2005 02:02 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read

16th April 2004, 01:13 AM	#3
SQ Kid diyAudio Member Join Date: Apr 2003 Location: MA	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.....

16th April 2004, 05:32 AM	#4
billr diyAudio Member Join Date: Dec 2003 Location: new zealand	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

16th April 2004, 05:13 PM	#5
SQ Kid diyAudio Member Join Date: Apr 2003 Location: MA	...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.

16th April 2004, 07:41 PM	#6
adamamp diyAudio Member Join Date: Mar 2004 Location: East of Eden	Just a guess but double check the interconnect AC socket/plug sometimes after 50 years they do not like to get wiggled Hope it works out so simple.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)