30-11-2015, 05:26 PM
(30-11-2015, 05:04 PM)pwdrive Wrote: NM, something would get hot, resistor/rectifier/mains transformer if fitted, possibly a fuse would blow if the radio had one, if no fuse then it would usually mean permanent component damage.
Most of the hard wired radio chassis had the wires wrapped at least half a turn around the connection points, dry joints were the most common problem, caused by poor soldering techniques including oxidization of component leads and connection points etc prior to soldering, it got worse when printed circuit boards were introduced.
Lawrence.
Well, the HMV had two 1 amp fuses between mains supply and transformer, mounted on the rectifier platform. I thought that was a good idea.
I tried using cable ties where I soldered a high voltage supply wire so if the solder joint ever came off, the wire wouldn't drop. I can only assume if that ever happened there would be a rapid equalisation of polarity between chassis and H.T. + with the 80 watt circuit in the middle. It must have happened scores of times in past years. One snag was there was no way to earth the chassis to an RCD as I think most radio chassis will have some voltage and current, even if small.
