How to use the drake tr7 as a vlf receiver

HOW TO USE THE DRAKE TR7 AS A VLF RECEIVER SERIAL
HOW TO USE THE DRAKE TR7 AS A VLF RECEIVER MODS

Most VFO tuned Japanese rigs of the time (and the Collins KWM-2A) did not have this scheme, which meant that the many local oscillators in those rigs were unlocked and each one of them would cause independent output drift on those rigs, without showing this on the display. Of course, the VFO can still drift (albeit small), but when this happens the display will show the drift as well so that you can compensate for the drift manually.

In any case, the result is an exceptionally stable rig with derives everything from a 40 MHz fixed reference frequency, including the digital display counter time base. The only radio that I am aware of that uses the same concept is the Kenwood TS-530S, hard to say who stole it from whom. The SSB carrier frequency generation is also inside the mixing scheme, which means the rigвЂ™s output frequency cannot drift if the SSB carrier frequency drifts (which concept also allows for the nice working pass band tuning on this rig). A 500 kHz span VFO (5MHz to 5.5MHz) is then used INSIDE the PLL loop for the fine tuning inside a selected band. A 500 kHz digital synthesizer is used, which generates the local fixed frequencies for each 500KHz band. To list a few:ДЎ)The PLL concept is really smart. The radio has a couple of features that make it special. Drake really took a huge risk at the time by pushing the limit for an all-solid state, PLL synthesized rig. The Drake TR7 is an incredibly smart design, it was way ahead of its time when it came out. It had a problem but it was easily fixed (defect PIN diode switch for the calibration marker which caused a low output at 10 meters, a common problem with the Drake)

HOW TO USE THE DRAKE TR7 AS A VLF RECEIVER SERIAL

But I recently was able to get a very nice one again with a high serial number, a Drake TR-7A, one of the last ones built.

I had one more than 20 years ago and always regretted selling it. The Drake TR7(A) is my all-time favorite vintage transceiver. These plug in directly to the S-Meter and Dial Lamp Sockets.Д®xcellent design from Drake, way ahead of its time! I simply removed the glass envelope from the dial lamps, and installed a small piece of perf board with either one or three Bright White LEDs.

HOW TO USE THE DRAKE TR7 AS A VLF RECEIVER MODS

The only Mods I've performed were to replace the incandescent Dial Lamps with LEDs. My Drake's drift for the first 30 minutes from a cold start, then remain solid enough to work FT8. Only the Ten-Tec Delta II, with it's 8-Pole Filter, comes close to digging a signal out of the mud. The Drake TR-7 and R-7, used as Twins can work DX under very marginal conditions. I've owned a lot of fine transceivers and seperates over the years. Mine is a high serial number, Split Back, with NB7A and all Filters. And it's a joy to work DX on the Ham Bands. The TR-7 receives down to 5 kHz if you remember that the LF/VLF Antenna Connection is on one of the Cinch-Jones Connectors. The TR-7 is easy to repair and maintain if you take time to read the Service Manual. The VCO Board JFETS had gone out on both - HI OSC on one and LO OSC on the other. I purchased my TR-7, and R-7, which I still own. In 1993 I was employed at HP making a great living. For many years after selling Portland Radio Joe was the guy to send your TR-7/R-7 to for repairs. Joe, and our Tech Dan Raab owned, and repaired the 7-Line.

I settled for a used set of B-Line Twins. Despite my employee discount, they were out of my price range. When the TR-7 came to the Amateur Radio market I was in my mid-20s and sold them at Joe Borsch's (W7PNS/SK) Portland Radio Supply Company.

How to use the drake tr7 as a vlf receiver