On Mon, 08 Sep 2008 11:20:31 GMT, (Graz) wrote:

Hand-soldered, 9-transistor Sanyo radio still works perfectly after 50
years!

What is the most likely failure mode of similar radios - dry joints?

If the radio only plays oldies and 1950's rock-n-roll, you have a
problem.

Dry joints? I've never had to lubricate my solder connections.

In order of frequency:
- Leaky batteries and corrosion damage.
- Grease on moving parts (tuning capacitor, volume pot, on-off switch)
has dried out.
- Bad electrolytic caps
- Loudspeaker coil rubbing on magnet. Warped cone.
- Carbon comp resistors changing value.
- Difficulty finding schematics and docs.
- Package leakage on the old round cylindrical xsistor packages.
- Tiny xformer wires corrode.
- Crumbling plastic parts, rotting fake leather, peeling chrome
plating, peeling labels, and faded decals.
- Rubber embitterment, especially the power cord.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558