Where there was supposed to be 120 Volts, there was 90 Volts. Where there was supposed to be 134 Volts, there was 119 Volts. BINGO! ALL the 'B+' (aka ' Plate Voltage') voltages were way off. These are pretty simple circuits, and it was starting to drive me batty., so I dropped back to the basics, and started checking the voltages. I replaced several coupling capacitors between stages, as if they get leaky, and pass DC voltage, they can throw the bias voltage to the following stage off. So, I started checking the resistor values that set the bias, and found several resistors that were out of tolerance, and replaced them.

One of the waveforms was 'clipping', which meant the tube wasn't operating in it's Linear Region, and it looked to me like it was biased wrong, as only one part of the waveform showed the clipping. This in NOT one of the better assembled kits I've seen, and while it may have 'worked' in 1967, it would have caused problems today.Īfter replacing the parts, I did the initial checks, and started the calibration. Some things had solder globbed on them, some had cold, grainy looking connections, and three connections were barely soldered. Replacing the old parts showed the soldering was not up to standards. It was full of loose hardware, both holding things down, and providing ground returns on the tube sockets and terminal strips.

First, I tightened all the loose hardware. This started out as a simple capacitor replacement, checkout, and calibration.

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