[MRCA] BC-654 Project 1.4

[Ray Fantini]

Thanks everyone for the help with the VBP-1, informed the sets owner and it should be on the way. Will work with the one working VS-3 that I have for now. Built a cable that has an eight-pin connector on one end and lug terminals on the other for running the receiver on the bench and working on getting everything sorted on the receiver before attempting to change the coverage. Attached are a couple pictures of before and after, all the electrolytic and big black capacitors were bad. Did pull several mica capacitors in the converter and IF stages and replace but examination of the micas showed that they were all solid so not going to mess with the others. Also discovered a couple of the 1N5 tubes were week and replaced them, whoever designed the tube shields should be taken out and shot. Wanted to remove the shields to clean the tubes but that's a choir. Got sensitivity up about where it should be and have plenty of audio when driving six hundred Ohm headphones but no so much when trying to drive an eight Ohm speaker but that's expected. Biggest issue now is I noticed that the AVC action is not all it needs to be on strong signals. May have an issue with the decoupling capacitors on the AVC bus, little leakage on those makes a big difference.
The next item after the receiver is finished will be the power supply, already started with the vibrator replacement and will also have to visit the Dry Disc Rectifier issues. The receiver power pack will benefit from several new solid-state devices that will all be covered under part two.

Ray F/KA3EKH

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