Running Using Batteries

Some excellent and simple advice on how to really improve reception on a portable receiver: run the radio using batteries.

Sony CRF-5100 Earth Orbiter

RadioIntelligencer has an interesting article about the Sony CRF-5100 Earth Orbiter, which Sony produced in the 1970s. This receiver covered shortwave, mediumwave, and longwave; the FM band; the air band; and the "public service" band on VHF. This was a good radio. It was my father's purchase of an CRF-5090 Earth Orbiter in 1975 that got me interested in radio (the 5090 is the same radio as the 5100 except that it lacks the public service band). That 5090 is long gone, but I now own a 5100 I bought used last year. It was an enjoyable radio to use in 1975 and it still is today.

My Old New Realistic DX-160

I got interested in radio as a hobby back in the 1970s when my father bought a portable Sony shortwave radio. After a couple of years I wanted a more substantial receiver, and since this was the '70s, the obvious place to find one in a small Canadian city was at the local Radio Shack store. In Feb. 1977, after saving for months, I purchased a brand new Realistic DX-160. That DX-160 became my DXing radio for shortwave, mediumwave, and longwave, and it got heavy use for the next eight years. For a time I also used it as the receiver at my amateur radio station.

But after eight years, the bandswitch seemed to be wearing out. I had to fiddle with it a lot to just get the radio to work and as time passed this problem only got worse. I was also losing interest in radio as a hobby around then. After 1985 I only occasionally did any DXing, and I quit entirely in 1987, not returning to it until 2000. So the DX-160 ended up sitting unused on a shelf as a keepsakee. It powered up but didn't receive anything. I never got rid of it, but never used it either.

Recently, however, when I saw some ads for DX-160s for sale online, I thought it would be nice to have a working one again. Which made me think that maybe I should get mine fixed, or fix it myself. So I went on the web to look for information about replacing the bandswitch. And there I found several DX-160 owners talking about their bandswitch problems. In most cases, their bandswitches had failed not because they wore out but because the contacts were oxidized so that no electrical connection was being made. They reported that using electronic contact cleaner often fixed the switch. I decided to try it.

Two weeks ago I went to Active Tech in Toronto and bought a can of contact cleaner. That evening I opened up my DX-160, blew out the dust, and then carefully squirted contact cleaner all over the bandswitch and into all the other switches and moving electronic parts. The result? The radio is working perfectly. The bandswitch is working fine. The radio doesn't seem to have lost any of its sensitivity - I set it up at my listening post and hooked it to my antenna and it is receiving just as well as my other, much newer, receivers.

I still can't quite believe that I've been thinking for over 20 years that this radio was broken and needed repairs, when in fact the only problem with it was that some contacts were dirty.

Two New Ultralight Radios

I recently bought two new ultralight radios. Two weeks ago I got up a Sangean DT-400W at Durham Radio in Whitby, Ontario, and yesterday I bought a Eton E-100 at the Durham Radio table at the York Region Amateur Radio Club hamfest. Good deal on the E-100: they were selling them for only $44.95. I'm not going to start DXing with either of these yet. I want to reach 200 stations in the ultralight log using the Sony SRF-59 before I start using any other radios. But after 200 I think they'll both be used a lot.