Main board in testing, others nearly complete

EVERYTHING BUT POWER TRANSISTORS INSTALLED ON MAIN BOARD

The assembly and checkout instructions for the main board ask me to defer installing the three power transistors and two transformers until after I complete a number of tests on the board, so these five parts are not installed. Everything else is soldered in place and I believed I wasready to start testing. 

BACK PANEL COMPLETE AND FRONT PANEL WAITING ON PARTS

I need a connector that was on back order and out of stock at all distributors, but I found a compatible one from another maker that I ordered today. 

FRONT BOARD COMPONENT INSTALLATION PROCEEDING

I installed all but one resistor and all but two surface mount capacitors, then added on some of the through hole parts and connectors. This board mounts the control switches and potentiometers that will emerge through the front panel which is sandwiched right in front. 

CHECKOUT OF MAIN BOARD

This involved a number of measurements to ensure there are no shorts on key power rails before first applying 115V. It checked out fine. 

Next I wired up the board to an electrical outlet and check for proper voltages on the various rails. Everything was good again. 

This board also generates rectangular and triangular waves which I will verify using a scope. I ran out of time today but will finish this off on my next shop visit. 

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