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Old 23rd June 2004, 07:18 PM   #1
harhaug is offline harhaug  Norway
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Default 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
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Old 23rd June 2004, 08:09 PM   #2
gl is offline gl  United States
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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
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Old 23rd June 2004, 08:21 PM   #3
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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.
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Old 23rd June 2004, 08:35 PM   #4
jam is offline jam  United States
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Mr. Pass and Harland,

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

Regards,

Jam
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Old 24th June 2004, 02:17 AM   #5
Tom2 is offline Tom2  United States
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Default 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
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Old 26th June 2004, 07:04 PM   #6
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Gl has graciously sent a number of schematics. I'll post
them shortly.
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Old 30th June 2004, 08:29 PM   #7
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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

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Old 30th June 2004, 08:40 PM   #8
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Quote:
Originally posted by Nelson Pass
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


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

Jan Didden
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Old 30th June 2004, 08:50 PM   #9
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Old 1st July 2004, 02:36 AM   #10
anatech is offline anatech  Canada
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Many Thanks Nelson!
Got one for a Nakamichi PA-7?
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