MCI JH 618, Rise from the dead!

In the late 70's, over half of the records in Billboard's Top 200 were recorded and/or mixed using MCI equipment.

Moderator: brianroth

Re: MCI JH 618, Rise from the dead!

Postby Ryebot » Mon Feb 26, 2018 11:53 am

As requested, some pictures:

IMG_0074.jpg

Before... (old bolster upholstery.)


IMG_2576.jpg

The lower motherboard in the master section looks like it had some bad dental work done by the previous owner(s) but it beeped out fine!


IMG_2935.jpg

in progress...


IMG_2952.jpg

Some of the mic pres have this type of mod. Jim Williams, is this similar to what you've described?


IMG_4193.jpg

Family portrait :-) JH 110 C from 1984 in decent shape! It will be the next project...

I re-capped re-socketed and re-chipped the Master and Monitor Module- with the exception of the tantalums. The distortion is still in the 2Mix output, but not when patched from Stereo Out to Aux in. Could it be the tantalum caps? The master fader? Or perhaps one of the J111s?

Jim, I'm moments away from sending my other Master module to you to work your magic, and then I might have both flavors available...

Thanks to all for your interest, advice and encouragement!

Best,

Ryebot
Ryebot
Analog Enthusiast
 
Posts: 6
Joined: Thu Sep 07, 2017 1:09 pm

Re: MCI JH 618, Rise from the dead!

Postby Jim Williams » Mon Feb 26, 2018 12:25 pm

That mic pre card only has the output el cap replaced with an Elma? and a Wima poly film bypass cap.
The 5532/4 opamps are still there with the same messy biasing scheme. I change all of that. Only the LM394 transistor front end is retained. It ends up being a total redesign with different resistors, re-wired bias from the opamp outputs and the psu caps are changed and moved.
Jim Williams
Audio Upgrades
Jim Williams
Yacht Rocker
 
Posts: 370
Joined: Mon Jul 14, 2008 9:58 am
Location: beautiful Carlsbad, CA

Re: MCI JH 618, Rise from the dead!

Postby Sirbastian » Sun Mar 04, 2018 5:32 am

Thanks for the pictures, looks great!!
Sirbastian
Analog Enthusiast
 
Posts: 17
Joined: Tue Oct 12, 2010 5:18 pm

Previous

Return to MCI Recording Consoles

Who is online

Users browsing this forum: No registered users and 1 guest

 
Mr Patchbay sells patchbays, tt/bantam cables and more