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michaelj
04-25-2008, 05:36 PM
New to this forum with question for the group.

Any one familiar with the " Bedrock 1200" series amps. I have one of the early ones [PTP turret board] from one of the local high school kids for repair.

Toasted the output tranny. [Patrick at MM is building a repacement.]

Anyone out there with a "GOOD" ie readable copy of the schematics and "factory" specs ie voltages, bias etc.

Any info would be appreciated.

Mike

lowbrow
04-25-2008, 06:21 PM
email Jay at guitarfetish.com...there's a link on the website. He was Bedrock amps and that's his current endeavor.

michaelj
04-26-2008, 12:06 AM
Thanks for the tip I went to the guitarfetish web site but could not find any contact or e-mail addresses. If you have a better e-mail link or address I would appreciate it. Me not finding it where you directed me could be yet another failure af an analog guy in a digital worls.

Thanks Again
Mike

Jag
04-26-2008, 12:50 AM
There's a link at the botton of their info page.
http://store.guitarfetish.com/info.html

lowbrow
04-26-2008, 01:04 AM
info@guitarfetish.com

You need to put something specific in the subject line to defet the spam filters. I would say Bedrock amp question for Jay perhaps.

michaelj
04-26-2008, 01:08 AM
THANKS GUYS !! GOT IT AND AM IN TOUGC WITH JAY.

WAITING FOR HIS REPLY TO MY QUESTIONS.

Mkie

DCinDC
04-26-2008, 01:11 AM
try jay@guitarfetish.com

I used to have a schematic for that amp, so they are out there on the net somewhere. That's where I would've got it. Did you try the blueguitar.org ftp site?

Bruce / Mission Amps
04-27-2008, 09:05 PM
New to this forum with question for the group.

Any one familiar with the " Bedrock 1200" series amps. I have one of the early ones [PTP turret board] from one of the local high school kids for repair.

Toasted the output tranny. [Patrick at MM is building a repacement.]

Anyone out there with a "GOOD" ie readable copy of the schematics and "factory" specs ie voltages, bias etc.

Any info would be appreciated.

MikeHere's what I have used ... I think is not the turret board version but it could help.
I also have trouble reading the schem so maybe the parts list can help you fill in the blanks.

michaelj
04-28-2008, 05:13 PM
Thanks Bruce, I did have that one and it is "helpfull" but a bit different than mine... I will muddle through and just bring it into " acceptable specs".

I did get ahold of "Jay" via e-mail and his comment was " That amp has been out of production for 10 years and I have no information or any thing to do with them", so that seems pretty clear.

It appears to me that these may have been designed to run "HOT"... DVM readings with out replacing any components are:

Plate on EL34s 589vdc
Screens 590vdc
BIAS - 58vdc

So I think I'll do some mods on the and G3 circuit to bring it more into line with the Marshall/Park levels of 490 to 530vdc, and add an adjustable bias network, replace th OT and see what we have. May set it up to Run KT66s as well. I'm old enough that I can remember those early Marshalls and 34s can be a bit brittle to my ears these days.

Thanks again for all the help.

Mike