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The Oak Hills Research OHR 100A single band CW transceiver kit is offered in 80, 40, 30, 20, and 15 Meter versions. Each can be aligned to cover 70-80Khz in a fairly wide band, but here are the defaults for which detailed specification is provided in the manual:

  • 15M 21.000 – 21.070
  • 20M 14.000 – 14.070
  • 30M 10.100 – 10.170
  • 40M 7.000 – 7.070
  • 80M 3.500 – 3.570

… or other 70-80KHz segment of relevant bands

The major features of the OHR 100A are:

  • 5W output on each band (4 to 4.5W on 15M), adjustable from a few mW to full power.
  • Single signal superhet receiver design.
  • New ultra stable pre-mix VFO system providing high side L.O. injection.
  • Local Oscillator signal is available at rear panel jack for use with the DD-1 digital dial.
  • RIT with a range of ± 1KHz.
  • Four pole crystal IF filter (we match the crystals).
  • IF bandwidth front-panel adjustable from 1200Hz down to 400Hz.
  • True sine-wave side tone (not square wave or sampled RF), with adjustable pitch and volume.
  • Silky smooth QSK.
  • Precision 10K VFO tuning pot with frequency index on the front panel.
  • Separate RF and AF gain controls provide for maximum comfort in noisy conditions.

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All wiring to the single PC board is terminated with pre-assembled Molex connectors, rear panel connectors and controls are mounted on the circuit board..

If you’d like to view a block diagram of the OHR100A, click here.

An oscilloscope is NOT needed for alignment. The Oak Hills Research have provided DC test points on the board for use with your digital voltmeter during alignment. 3.5mm jacks are provided for headphones and speaker. There is also an on board shorting plug to select stereo or mono headphone operation. There is room filling audio available at a separate speaker jack.

The OHR 100A will operate on 12 – 13.8VDC. The current drain is 80mA on receive and 850mA on transmit with 13.6VDC supply voltage. The 15 and 40 meter versions are easy to set up for operation in the novice portions of the band.

For finer tuning, a high-precision ten turn pot is available (part number MO-100AP). It’s supplied with a matching knob and instructions for $15.95. Note that if you install the ten turn pot, the front-panel dial markings will no longer be relevant and use of the DD-1 digital dial is recommended.

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The power LED kit is optional because it will increase current requirements by about 50mA on both receive and transmit. It requires drilling a 1/4″ mounting hole in the front panel but is otherwise a very simple and attractive mod based on a pre-wired LED and bezel assembly.

The OHR 100A comes with a high quality SO-239 antenna connector. But if you would prefer a BNC connector, you’ll find a conversion kit on their Page.

Prices:
Transceiver kit:
OHR 100A for 15M (21MHz), $149.95
OHR 100A for 20M (14MHz), $149.95
OHR 100A for 30M (10.1MHz), $149.95
OHR 100A for 40M (7MHz), $149.95
OHR 100A for 80M (3.5MHz), $149.95

Accessories:
Ten-turn VFO tuning pot for OHR 100A, $17.95
Power-on LED Kit for OHR 100A, $9.95
Electronic Keyer (basic) for OHR 100A, $29.95
Electronic Memory keyer for OHR 100A, $39.95

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