Friday, December 28, 2012

SB-310 Receiver Gets A Speaker

I was able to get a matching SB-600 speaker on eBay for my SB-310 shortwave receiver. It has some paint chips but is not too bad looking overall. Probably thousands of these speakers were sold by Heathkit for the matching SB and HW series radios from 1966 through 1975, retailing for US$17.95 They tend to go for quite a high price on eBay. I got mine for a good price - probably because the seller listed it as an "SP-600" rather than an "SB-600" so many potential buyers may have missed it in searches.

SB-310 and SB-600 Speaker
The restoration of this radio only consisted of putting on a new line cord, cleaning it, and touching up the alignment. I made some rubber feet using rubber stoppers cut to size and drilled for a screw. I initially thought it was missing the 100 KHz crystal but it was installed in the LSB crystal socket (which is normally empty) by mistake.
Another View of the SB-310 Receiver
It is a good performer, picking up lots of shortwave stations in the evenings. The dial is linear and very accurate.

Repaired Function Switch With Microswitch
I was also able to fix the main issue with my SB-310, the broken power switch. It is a combined rotary wafer switch and power switch on the FUNCTION switch. Getting a new switch is almost impossible. I was able to rig up a micro switch in such a way as to be controlled by the rotor of the function switch. Provided that the Gorrilla glue holding the switch stays in place, it should do the job.