This ad from sixty years ago, in the November 1957 issue of Popular Electronics, was for two little VHF rigs I had never seen before, from a company called Springfield Enterprises of Springfield Gardens, New York. The prices shown in bold print certainly look reasonable. The two-meter version is priced at $6.98, and the six-meter version is $14.98. But the fine print reveals that these are the prices for the chassis only. It is already assembled, but it doesn’t include the microphone, “miniature mike transformer,” headphones, or even the case. With these “accessories,” the price increases.
The description is lacking in details, but the two-meter version is a single tube with VFO. It’s probably similar to the transceiver shown previously at this link.
The six-meter version contains a crystal-controlled transmitter with variable frequency receiver, and uses multiple tubes. Both sets were billed as having a range of 1-5 miles with a built-in whip, and “much more with directional beam antenna.”
I’ve never seen any reference to either of these rigs, other than this K3DSM’s website, in which he states that he owned one of the two-meter versions.
Hi, I have uploaded some info about the Springfield Enterprise Two Meter Transciever, Plus a picture of me taken near mount wilson in Los Angeles talking with some guy near the coast I think. So obvouly the unit had a good range as long as you had line of site communication. Wasn’t very stable as you might imagine.
Here is a link to my Flickr photo album: https://flic.kr/s/aHskpX7Tkv
I and a friend built two of these in about 1956. They were true genius in minimalist engineering. One 3A5 tube as a super-regenerative detector/audio amp and a modulator/Hartley transmitter. Both sections of the tube were in operation all the time, with a 6 pole double throw TR switch. There were 4 size C flashlight batteries, two which lit the filaments of the 3A5 and 2 supplied 3 vdc for the carbon mike. B+ was from a large 90 volt photo-flash battery. There was a small round modulation/audio transformer. The tank was about 6 turns of ~ #18, silver plated wire — tapped — air wound about 1/2 inch in the center and tuning was by a nickel plated brass screw in the center. There was a lot of receiver noise and they would reach a couple of blocks. You had to switch to transmit and then key the mike to transmit.