|Swan 350 circa 1966|
I checked into the Swan Tech Net today and was told the S/N of this radio (C 618852) was manufactured in 1966 and that the radio was produced from 1964 to 1967. This one was late enough to have the one piece xtal filter instead of sockets for the individual crystals that the early ones had. During testing I measured the B+ ripple at about 3v. Stu K4BOV said that the it should probably be less than 1v so the filters are a bit weak. Stu suggested to use 80-220 mfd caps rated at, at least 350.
The Swan Tech Net is on Sat PM at 2:30-3:30 or so on 7235. Check it out sometime if you are interested in these oldies.