Projects

Swan 350 Project

I found a Swan350 transceiver from the 60's on eBay for an excellent price with free shipping! It is in very good condition but lacks the necessary power supply, A search of the innertubes showed me that the power supplies with built-in speakers (SW-117AC, 117C, 117X), were commanding a stiff price, so I found a 117B Swan power supply that does not come with a speaker. It actually was "free shipping" too, from California. a pretty good deal for such a heavy unit.

I replaced all the original electrolytic capacitors in the power supply. After a pretty thorough search, it seemed impossible to find replacements for the original electrolytic cans (80uf and 50uf @ 450VDC in the same can) with the same values. One can was insulated from the chassis so the working voltage could be doubled. Instead, I used axial electrolytics inside the chassis using terminal strips.

Replacing the two-wire, non-polarized line cord with a 3-wire one made a lot of sense. I also replaced the 2Watt resistors. The Cinch-Jones plug was in poor shape so replaced that too. The power supply 117B is unusual because the cable to the transceiver is run through a chassis cinch without a connector, so the only connector is on the transceiver end. This makes a bit incovenient to make a longer cable. After testing the power supply, it was time to move on to the 350.

The 350 chassis was very clean and must have been stored in a dry environment, as there was no sign of rust or corrosion. Since this particular model was produced in the late 60s, it looked pretty good for being over 50 years old.

First was the electrolytic can on the 350 chassis. It had a 40uf, 30uf, 10uf all at 450VDC and a 25uf @ 25VDC. Chances of find a direct replacement were mighty slim, so I elected to replace them with axial electrolyics under the chassis. Also, replaced a couple of other non-disk caps at the same time.