From the manual:
|Frequency Coverage||80 meters, 3.5 to 3.75 MHz|
|40 meters, 7.0 to 7.25 MHz|
|20 meters, 14.0 to 14.25 MHz|
|15 meters, 21.0 to 21.25 MHz|
|Frequency Stability||less than 150Hz/hour drift after 60 minute warm-up|
|Frequency Generation||premixed VFO and HFO|
|Power Requirements||13.4 volts DC, nominal. 90mA receive mode and 430 mA transmit mode|
|Dimensions||9-¼" wide x 8-½" deep x 4-¼" high, including knobs and feet|
|(23.5cm wide x 21.6 cm deep x 10.8cm high)|
|Weight||4 lbs. (1.8kg)|
|DC Power Input||80 meters -- 3.5 watts|
|40 meters -- 3.0 watts|
|20 meters -- 3.0 watts|
|15 meters -- 2.5 watts|
|Frequency Control||built-in VFO|
|Output Impedence||50 ohms unbalanced|
|Sidetone||built-in, adustable volume|
|Spurious and |
|at least 35dB down|
|Transmit Frequency Offset||approximately 750 Hz lower, fixed on all bands|
|Receiver Type||direct conversion with RF amplifier, balanced product detector, and active audio filter|
|Sensitivity||1 microvolt or less for 10dB (S+N)/N 0.2 microvolt provides readable signal|
|Selectivity||Wide -- 750 Hz at 6dB down|
|Narrow -- 375 Hz at 6dB down|
|Passband Center Frequency||750 Hz|
|Type of Reception||CW|
|Audio Output Impedance||1000 ohms nominal|
The HW-8 was the second QRP transceiver offered by Heathkit. It replaced the HW-7 and was offered between 1976 and 1983. While it looked similar to and was the same size as the HW-7, the HW-8 featured a much more sophisticated direct-conversion receiver design and included 80 meters. In all respects, the HW-8 is a rig far superior to the HW-7. The original price of the HW-8 was $139.95.
I have owned two HW-8 transceivers. An unmodified HW-8 was the first rig I purchased following the 1989 fire. This was my only HF rig for some time and many contacts were made with it. I implemented several simple mods within this HW-8, including a fix for transmitter offset and the installation of an internal 100kHz crystal calibrator.
I sold this rig to help pay for the QRP Plus but soon regretted having let it go. After I purchased an HW-7, seeing it on the shelf only served to make my longing for another HW-8 stronger and I finally purchased another HW-8, the one I currently own.
The HW-8 is designed for use with high-impedence mono headphones. Before I found a proper set of vintage Trimm Featherweight headphones, I used modern low-impedence stereo headphones with an impedence adapter (image) built around a Radio Shack #273-1380 audio transformer.
I have installed a Small Wonder Labs Freq-Mite (link) in my HW-8; this clever frequency counter announces the VFO frequency in morse code in the headphones at the press of a rear-panel button, allowing me to know my precise frequency no matter where on the dial I am. Because several hams have asked about this installation, I've written up instructions.
An extremely useful reference on the HW-8 is Michael Bryce's HW-8 Handbook, Second Edition. This book provides circuit descriptions, schematics, board layouts, alignment instructions, Heathkit service bulletins, and modifications for the HW-7, HW-8, and HW-9. It is available at Michael Bryce's The Heathkit Shop, at Kanga, USA, and at QRP ARCI. The older, First Edition, HW-8 Handbook has modifications for the HW-7, HW-8, and HW-9 but lacks the other valuable content.
The articles written by Adrian Weiss, W0RSP, for CQ Magazine (May, 1977; August, 1977; October 1977; January 1981; and October 1982) are also valuable resources worth looking for.