R.L. Drake SW-4A, alive and kicking!
I fired up the SW-4A this morning, and I'm monitoring Radio Australia, at 0915
UTC, on 9590khz. I've got it hooked up to the Antenna Supermarket Eavesdropper SWL Sloper. I'm the original owner, and no I'm sorry, but it's not for sale. I purchased it in 1975, from Trigger Amateur Electronics, in River Forest, Illinois, a suburb of Chicago. I've never had to change a tube, or a filter capacitor, and the crystal controlled direct frequency dialing is still dead-on accurate.I believe this was the first shortwave receiver to offer the crystal controlled direct frequency dialing. I'd be interested to know if anyone has one in their shack, and how it's holding up. Good DXing to you from the Chicago burbs, Gary |
"Kachina 78" wrote in message ... I fired up the SW-4A this morning, and I'm monitoring Radio Australia, at 0915 UTC, on 9590khz. I've got it hooked up to the Antenna Supermarket Eavesdropper SWL Sloper. I'm the original owner, and no I'm sorry, but it's not for sale. I purchased it in 1975, from Trigger Amateur Electronics, in River Forest, Illinois, a suburb of Chicago. I've never had to change a tube, or a filter capacitor, and the crystal controlled direct frequency dialing is still dead-on accurate.I believe this was the first shortwave receiver to offer the crystal controlled direct frequency dialing. The radio's local oscillator is only half crystal controlled. The bands are determined by which crystal is switched in and the actual local oscillator frequency is determined by a permeability tuned oscillator. Similiar PTOs (without crystals) have been used in car radios for decades. Other Drake radios going back to the late 50s have used pretty much the same setup. Drake's PTO setup has very good frequency stability and is easy to tune. I'd be interested to know if anyone has one in their shack, and how it's holding up. Good DXing to you from the Chicago burbs, Gary I bought one off from another contributor to this group. It's still a good performer, and I like it. However, some of my other radios suit me better. I like to spin a main tuning knob across several bands to get a sense of what's hot at that time. I then tune across a band using a bandspread dial. The Drake, with it's 500 kHz bands and preselector, is alsmost imposssible to be used this way. Also, there's many more stations outside the Drake's tuning range these days. Frank Dresser |
"Frank Dresser" ) writes: "Kachina 78" wrote in message ... I fired up the SW-4A this morning, and I'm monitoring Radio Australia, at 0915 UTC, on 9590khz. I've got it hooked up to the Antenna Supermarket Eavesdropper SWL Sloper. I'm the original owner, and no I'm sorry, but it's not for sale. I purchased it in 1975, from Trigger Amateur Electronics, in River Forest, Illinois, a suburb of Chicago. I've never had to change a tube, or a filter capacitor, and the crystal controlled direct frequency dialing is still dead-on accurate.I believe this was the first shortwave receiver to offer the crystal controlled direct frequency dialing. The radio's local oscillator is only half crystal controlled. The bands are determined by which crystal is switched in and the actual local oscillator frequency is determined by a permeability tuned oscillator. Similiar PTOs (without crystals) have been used in car radios for decades. Other Drake radios going back to the late 50s have used pretty much the same setup. I was going to comment on that line, but then I suddenly couldn't remember the mixing scheme of the receiver. I seem to recall that it used premixing, ie the variable oscillator is mixed with the crystal oscillator to provide the signal needed for the actual signal mixer. I know that was done in some of the Drakes, getting away from the scheme used in their earlier receivers where they had in effect a receiver that tuned a fixed 500KHz range, and then a crystal controlled converter ahead of it to get the various bands. The premixing has the advantage that another mixer isn't in the signal chain to overload, though I think it's up in the air how much else it might save since one has to filter that output of the premixer well to avoid spurs. But since I couldn't remember if the SW4 used premixing or not, I wasn't sure if that was what the poster was talking about, though his term "crystal controlled direct frequency dialing" is rather ambiguous. And of course, Drake wasn't the first to use the scheme of a tuneable receiver with a crystal controlled converter ahead of it. The date from the late forties or early fifties in some commercial receivers, with Collins likely being the first to issue such receivers. Michael |
Chuck Harder, www.forthepeople.org www.chuckharder.com (don't
forget to click on the Suwannee River music thingy) used to push them Drake R4's.Chuck Harder used to say take your Drake R4 shortwave radio outside and get it away from that stuff inside your house that messes up your radio reception. cuhulin |
I used to work at an auto/truck/lawnmower factory in
Florence,Mississippi.Looka here,,, do y'all have any idea whatsoever about 100 percent pure sulphuric acid! I Gurrantee y'all,y'all DON'T want to mess around with that stuff!!! cuhulin |
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