Friday, July 1, 2016

Part 4: MCI JH110B Rebuild - We Got Sound!

By Tim Dolbear

A bad cap on the left channel's Repro Board was causing a resistor to blow spectacularly and with both parts fix and the IC that they supplied -18v to also replaced for good measure, we have sound!

And even at this point it sounds COOL!

Big thanks for the help of Dan Hembree, my wife's brother, who used to work at Rupert Neve Designs and now owns

The machine is not setup yet correctly for Bias/levels so we are running it with the settings the old owners had for the tape they were using, but we are able to record and listen back to tape! New MRL tape should be here in a couple weeks for final setup.

One last issue we are tracking down is that the transport controls still are acting up; FF and RW work perfectly, then the motors stop responding to the buttons, again, the lifters still worked. The joystick still RW and FW but the motors will not moved when pressing RW or FF.  Also the stop sometimes will not stop playback meaning when you push the stop bottom the machine stops, but releasing the stop button and play resumes.

While trouble shooting I unplugged the MVC (Joystick shuttle) board and now the controls are all solid. I suspect the sensitivity is set too high and its triggering something or simply there is a bad part.  I will not use the MVC but without it's little board plugged in, the RTZ no logger works. so...

Next I need to build the switching system that will allow me to add the JH110B into the Mixbuss Loop I use while mixing, and allow for playback to the DAW or straight to the monitoring. I am not a fan of patchbays, and thus the switching system. Stay tuned.

On ward!


  1. So, I am assuming that EVERYTHING will be analog til the very last stage of recording. :)

  2. Hybrid. I work on a Sequoia DAW and my mix buss leaves Sequoia via a Mytek D/A, into a Great River EQ-2NV into a Manley Mastering Edition Variable Mu with HP and TBar Mod, then it will be captured to 2track tape and/or back to Sequoia.