Looking around for information on Interstage Transformers I found this.
Figured I'd share it here...
Discuss?

Of course I reassembled the amplifier bolted everything down and closed the lid....
well, I missed something....
bulb is bright
No Voltage on the rails
I just powered down the bench and locked the door.

Roly!
Thanks for the Guidance I'm Glad I didn't go ahead with the larger Wattage Bulb.
The reason I asked about the light bulb wattage is that I have a Sunn Concert Slave that Oscillates with a 100W bulb in series but operates normal on straight line voltage...and previous to this Trace Elliot, the Sunn was the largest SS amplifier I have ever worked on. I attributed the Oscillation to the 100W bulb not passing enough current to run the PowerAmp.

Ok, I hope to get back to this amp soon. Open it back up and figure out what I did wrong, or what I missed.

ok, should be able to finish up tonight... I need to verify my work and Reassemble... I dont know what the Idle Current draw for the Amp would be...
Will 800mA be enough to fire this up.
Should I use a larger Wattage bulb than 100W?

I believe that I will go with the BUZ901/906p. The amount of re-fabricating to mount the IRF's Would eat up any savings that may be had.

Here is a sampling of shots...

Yeah, the $70 was all Four MosFets in the TO-247 package...I think with Shipping and what not, they work out to Approx. the same...Too Much!
Modifying the circuit may be the way to go. I will post some board shots when I get to the Lab computer.

haha!
Looks like I can score Semelab BUZ901P/BUZ906P from Newark/Element 14....@ $70usd +shipping...
or the Gamble on a "respected" ebay dealer with pairs of the Hitachi version @ $15shipped = $30 total...buy 3 times the quantity needed for the same price...for 3X the headache? haha!

Good Eye!
I have alerted T.E. to the issue.
in the meantime...I have marked up the existing schematic with these corrections.
I breezed over the board node by node with the meter and did not notice anything else out of place.
I guess what I really need to do is figure out what/where I'm going to score the finals...

Yeah, I was on that track...have the PA board out, MosFets out, FilterCaps out...Tracing and Marking...Plenty of room for error. haha!
Anyway, T.E. dropped this to my inbox...below.

TR7 and TR9 are done for.
R13 is charred.
R3 is brown.
Was not blowing fuses, Was not passing signal, Was not brightly illuminating the lamp.
Transformer and DC rails be good.

Upon closer inspection...
I have found that the Mosfet board is very similar... I did take some board shots and will trace it out as I get time...
2sk1506 and 2sj162...so that's not too fun.

Hello,
I have this amp opened up and am looking for a PA Schematic.
Chassis was QC'd in 1994
It is not either of the PA boards covered in the GP7 150-300W manual.
Although it is very similar to the Mosfet Power Board...Designators are different, values vary, and...
I do have a request in at Trace Elliot via E-mail...but no response as of yet.

Hey there dpost...
A guick google search shows the schematic is posted up over at music-electronics-forum...
"acoustic 370 voltage intermittent"
See if that is what you need...

 :tu:
Anyone?
http://earth.ampage.org/

http://earthsr.proboards82.com/index.cgi
yet another amp forum

well,
That didn't last.
got a bad cap in there and now it's making a HELL of a lot more noise than when I started.
o.k.
This time I buy caps from mouser.