Threshold 400a manual/schematic needed.
 

Hi.

I would like to get my hands on a schematic, or better yet, a service manual for the Threshold 400a. Mr. Pass didn't have it. Anyone?

- Thanks

Harald

harhaug,

I have a factory schematic for this and the 4000A. This is the second request to come up in the last week or so. I don't have the facilities to scan files so I have put these and others into the snail mail to Mr. Pass. He should have them in a few days. Perhaps he would be kind enough to post them.

Graeme

I believe Jon Soderberg at vintageamp@earthlink.net sells
copies. If not, maybe Jam has it. If all else fails, I can reconstruct
most of it from memory.

Mr. Pass and Harland,

I might have it. Let me check and I will let you know tomorrow.

Regards,

Jam

400A schematic
 

Mr. Pass,
I also have a 400A schematic. I reversed engineered the main
circuit board along with the power output stage board/heasink
assembly of one of the channels some time ago.

It shows all the components.(I think)
It has all the resistor values, some of the semiconductor numbers
and some of the capacitor values.

Perhaps you could fill in the unknown electrolytic capacitor values.
I am planning to change the electrolytics soon in my 400A.

I can copy it and send it to you.


Tom

Gl has graciously sent a number of schematics. I'll post
them shortly.

Sorry about the delay. I edited a swell copy of this schematic
but I keep forgetting to bring it in and I can't ftp from home.

so use the original 500K tif:

www.passlabs.com/np/400a-4000.tif

:cool:

My god Mr Pass, you've come a long way indeed!

Jan Didden

Progress is our most important product. :cool:

Many Thanks Nelson!
Got one for a Nakamichi PA-7?