A silent key that recently passed away happen to have two kits that were never built and his wife was nice enough to contact me and see if I wanted to purchase them. I admit I had never heard of the company that made them or perhaps as old as I am getting I had forgotten their name. The first kit was a Oak Hill Research OHR-500 Five band QRP radio which originally sold for $356.00 unbuilt. This kit took just over a week to put together and the part that almost drove me to drinking was the silly toriods that had to be wound. Here are the specs for the radio and some pictures of the completed project. The radio does have the optional keyer built into it making it even sweeter.
The Oak Hills Research OHR500 is a five band CW transceiver that covers 150 KHz of the 80, 40, 30, 20 and 15M bands.
Some of the features include a super-quiet single signal superhet receiver, with diode ring mixer, and a new ultra stable pre-mix VFO system providing high side L.O. injection. The VFO is tuned with a high quality double bearing, vernier drive air variable cap.
Additional features include RIT, four pole crystal filter using hand-matched crystals, a four pole audio filter switchable from the front panel, and TX power out control on front panel. The receiver includes a high performance AGC circuit which can be turned off at front panel, separate RF gain control, true sinewave sidetone with separate frequency and level controls, and room filling audio at rear panel speaker jack in addition to the headphone output.
A scope is NOT required for alignment. We have included on-board RF probes so you can use your DMM and frequency counter for alignment. The L.O. signal is available at a rear panel jack for use with the DD-1 digital display.
The chassis is pre-punched for the optional keyer kit.
The OHR 500's transmitter provides 4-5 watts out on all bands except 15M which is 3-3.5 watts. The transmitter also has a silky smooth QSK circuit.
The kit includes a high qualtiy SO-239 antenna connector, with delrin insulator and gold-plated center pen for easy, reliable soldering. But if you would prefer a BNC connector, you'll find a conversion kit on our Parts Page.
The OHR 500 operates on 12 - 13.8VDC. The current drain on RX is 270mA and 1A on transmit. The completed transceiver measures (HWD) 4" x 8 1/4" x 8 1/4" and weighs 3.8 pounds. The kit is complete with cabinet, three high quality silkscreened printed circuit boards, all components and instructions. Click here for information about the optional keyers.
The second kit was the matching DD-1 Digital display which works with any number of radios whether it be this one or a Heathkit HW-7, 8 or 9. The digital display took about three evening of slow and careful work since the soldering is a bit on the tight side in places.
The good news is the first CQ I sent on 20 meters signing KG0MN/QRP landed me a contact with a gent in Spain and got a nice 579 signal running 1/2 watt into a 3-element yagi at 45'.
Now the sad news, the OHR-500 is no longer being made since some of the parts are no longer available. Hope you enjoy the info and I will answer any questions anyone might have.
73
Kevin ~ KG0MN/QRP
The Oak Hills Research OHR500 is a five band CW transceiver that covers 150 KHz of the 80, 40, 30, 20 and 15M bands.
Some of the features include a super-quiet single signal superhet receiver, with diode ring mixer, and a new ultra stable pre-mix VFO system providing high side L.O. injection. The VFO is tuned with a high quality double bearing, vernier drive air variable cap.
Additional features include RIT, four pole crystal filter using hand-matched crystals, a four pole audio filter switchable from the front panel, and TX power out control on front panel. The receiver includes a high performance AGC circuit which can be turned off at front panel, separate RF gain control, true sinewave sidetone with separate frequency and level controls, and room filling audio at rear panel speaker jack in addition to the headphone output.
A scope is NOT required for alignment. We have included on-board RF probes so you can use your DMM and frequency counter for alignment. The L.O. signal is available at a rear panel jack for use with the DD-1 digital display.
The chassis is pre-punched for the optional keyer kit.
The OHR 500's transmitter provides 4-5 watts out on all bands except 15M which is 3-3.5 watts. The transmitter also has a silky smooth QSK circuit.
The kit includes a high qualtiy SO-239 antenna connector, with delrin insulator and gold-plated center pen for easy, reliable soldering. But if you would prefer a BNC connector, you'll find a conversion kit on our Parts Page.
The OHR 500 operates on 12 - 13.8VDC. The current drain on RX is 270mA and 1A on transmit. The completed transceiver measures (HWD) 4" x 8 1/4" x 8 1/4" and weighs 3.8 pounds. The kit is complete with cabinet, three high quality silkscreened printed circuit boards, all components and instructions. Click here for information about the optional keyers.
The second kit was the matching DD-1 Digital display which works with any number of radios whether it be this one or a Heathkit HW-7, 8 or 9. The digital display took about three evening of slow and careful work since the soldering is a bit on the tight side in places.
The good news is the first CQ I sent on 20 meters signing KG0MN/QRP landed me a contact with a gent in Spain and got a nice 579 signal running 1/2 watt into a 3-element yagi at 45'.
Now the sad news, the OHR-500 is no longer being made since some of the parts are no longer available. Hope you enjoy the info and I will answer any questions anyone might have.
73
Kevin ~ KG0MN/QRP
After building those kits. I started restoring old tube rigs and giving new life to old amps and rigs.