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It might have another problem, or I might be doing it wrong. I put it back on the shelf, and I'll let it sit for a while, and redo the alignment. The alignment/calibration went per the book, but I don't like the way some of the adjustments acted when I was doing them. I changed it out for a 5 Watt rated part, and all the voltages returned to normal. Over the years, the heat took it's toll (common issue with Carbon Composition resistors), and it drifted high in value. This was a 2 Watt resistor, and it was dissipating about 1.5 Watts, which is too close to it's ratings. Turns out the 330 Ohm dropping resistor had increased in value to 560 Ohms, and was dropping excessive voltage. The problem was in the power supply section, something I normally checked, and since I had replaced the main filter capacitor, what could be the problem? Hey, Jim! Did you check the only resistor in the power supply? Uhhhhhh.no. 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.
![fm stereo generator kit fm stereo generator kit](https://i5.walmartimages.com/asr/218f0db4-6383-4611-bb99-ab6bdd94bb5d.ad177d8f396a76d3021a78b672c95561.jpeg)
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.
FM STEREO GENERATOR KIT FULL
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.