john hardy mcp 3000 pics/schemo needed

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Anyone got a schemo/pics of the johnhardy sony 3000 mic pre replacment parts. I got the one of the hardy website but still missing some details that I need...
The schematic on my web site is complete and is not missing anything. If you are looking for some other technical details separate from the schematic itself, please explain what they are.

The schematic on my site is for the revised version of the MPC-3000 card that I started making a couple of years ago. Prior to that the input bias current compensation circuit was done differently, using the +18V supply as the reference voltage instead of the dedicated zener diode and filtering that the newer card has.

Also, trimmer RV3 was not a part of the DC servo circuit of the earlier design. It is probably overkill to include it because the DC offset voltage would be below 150uV without it, but the addition of RV3 allows trimming the offset to below 10uV (basically to the point where you can't be sure what you are measuring anymore).

The schematic is available at:

http://www.johnhardyco.com/pdf/MPC3000.pdf

The "photos" are computer generated drawings of the p.c. board and the front panel. They are quite accurate in terms of the locations of everything, but the front panel is actually black with white markings. One of these days I'll take xome actual photos. Thank you.

John Hardy
The John Hardy Co.
www.johnhardyco.com
 
Thanks John. for some reason the windoz computer at work couldn't load up that PDF but got it when I got home. I should have deleted the post. but forgot to do so.
 
I once spoke to John over the phone when I was a punk kid working at a two bit guitar shop. I bugged this guy for two cheap 990 opamps while people are beating down his door for four grand worth of mic pres all day and night and I must say he was one of the nicest guys I've ever dealt with. He talked at length with me answering my dumb questions and was happy to send me the parts I thought I could use to build my own uber-pre.
I think John is just so confident he's offering a good product at a good price he doesn't care if you see what's under the hood.
 

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