X-101-C McShane kit electronic restoration

One thing I did with my DBT is convert it to a 3 way lamp socket. That way I can test low, medium and high powered gear with one bulb. Also you can vary the load to the dbt which also affects the voltage in the unit. I use a 50-100-150 bulb and it works real well with all gear.
 
I finished installing the remainder of the kit tonight, powered it up to test on the bench, and success. It sounded great through the minimus 7s.

Next I need to set the bias and phase inverter adjustments. But, I’m too tired to do any more tonight.

Here’s how everything looks under the hood with the new parts.
5863A040-32C5-4EEE-A306-BC97772F8955.jpeg
 
NOTE!!!! The BIAS VOLTAGE is spec'ed at 40V. This will result in voltages of 10V avg across the heaters in V1, V2, V3 & V4, and increased warm up times as the heater voltage is low. Last I heard 42V seemed to be popular with avg heaters of 10.5v or even 44v for 11V on the V1 thru V4 Heaters. 44v IIRC is really pushing the output tubes hard so 42v is probably the safe bet. Check with Dave G. on this tho as he'll have the latest info.

With the power off and unplugged. Use a jumper wire to GROUND OUT C27A to chassis, (lead goes to the center pin on the pot, just follow it back to the can cap, then ground that section of the can cap.). With an ohmmeter, check ohms on pin 1 and pin 3. Using the pot match pin 1 and pin 3 (pos lead of meter on pin3). NOTE sometimes it's reversed so if you get no action on pin 3, adjust pin 1 to pin 3. Repeat for 2nd channel. Your done. http://audiokarma.org/forums/index....-easy-400-phase-inverter-adjust.559415/page-2 bottom of page and http://audiokarma.org/forums/index....-easy-400-phase-inverter-adjust.559415/page-3 has the info on the x101-c.
 
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I set the bias to 40v, did the phase inverter adjustments, and installed it back into the Barzilay console for a test drive.

It sounds great.

Thank you, @larryderouin and @dcgillespie, for coming in my thread and helping guide a brother through. I appreciate you very much. I made this thread and posted the pictures to help the next brother down the line too.
 
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