Heathkit HW-8 QRP
CW Transceiver
1976-1993
80/40/20/15mtr 3 Watt CW Transceiver
This article REVISED from the original 1997 article in 2007.
In the 1970s, Heathkit discovered the QRP market that TenTec had already pioneered with their "Argonaut", QRP SSB and CW Transceiver. TenTec's Argonaut 505 ($280) was a compact 5W PEP SSB/CW radio that many a collector prizes today.
Heath introduced their "low cost, low power" 3 band HW-7 at $79.95. It was plagued with problems with eventually fairly easy fixes. Even with it's faults, it worked well enough to communicate when the kit was finished per the assembly manual.
The "new" HW-8 was introduced in 1976. It was a totally different design from the HW-7. The radio works as well today as it did when introduced 20 years ago ($129). There are many magazine articles, online web pages and the "HW Handbook" that includes information on HW-7, HW-8 and HW-9.
The HW-8 has an FET R-F Amplifier, product detector, active audio filter, sidetone, and covered the lower 250kc of 80/40/20 and 15 meters. Keying is a VOX type, with a fairly harsh sounding CW signal and almost QSK at slow speeds.
Power output is atleast 2 watts on 80 & 40, with 1.5 or so on 20 & 15 meters. The radios vary in output power. Some radios have as much out as 3 watts on 80/40/20, and 2 watts on 15 meters. Of course this slight increase can not be decerned at the receiving end of a QRP CW QSO.
The radio is powered by 12 volts DC, the RX current is about 85 ma, and on TX, 450 ma. The matching HW-7-1 AC power supply can supply 13.8 VDC at 600 ma, and has about 5% voltage regulation. The HW-8's RX sounds better, and it's TX signal a bit cleaner using a battery power source. Many add a "ferrite donut filter form" with a few turns of #20 wire to help filter the HW-7-1 AC Power Supply. It is a good idea to replace the filter capacitors in this power supply, as after 32yrs...they often leak and cause hum.
The receiver sensitivity on 80/40/20 is about .3 mv, with less sensitivity on 15 meters. The built-in audio filter is helpful in crowded bands. Experiment with various headphones as your results may vary. I had best results with 600ohm headsets, but the 30ohm usual miniature stereo headsets and others work OK too.
It has a relative power output meter on the front panel, and push-button band-switching. One large PC board contains most of the circuitry. The Cabinet is made of sturdy aluminum and easily opens for repairs or modifications.
Note: The mixture used in making the torroid coil forms often changes through the years, if you have problems with the output tuning properly, check the articles relating to the output coils,etc.
The HW-8 is a real QRP Classic, and the author of this article has repaired and owned several of these fine radios. The radio operates well with original circuitry, but there are many sources of "improvements" availiable. A good one of these radios is hard to find. If you find one...keep it! (I had to sell mine in 2007, but my memories of this radio along with some photos will always be with me.)
73- de WB6FZH
LINKS
- HW-8 MODIFICATIONS, REPAIRS & RECOLLECTIONS- Written 10/97 for old WB6FZH AOL Website.
- ORIGINAL HW-8 1997 Article- Written 10/97 for old WB6FZH AOL website.
- Trinity County Ham Radio Page- WB6FZH's Trinity County Info: Events, TCARC activities & Links.
- WB6FZH Classic and Military Radio Website- Boatanchors and various Ham Radio Pages.
MODIFICATIONS to RADIOS pictured: The HW-8 has an additional AC adaptor type power connector, SO-238 antenna connector and a wing-nut type Ground Connection. The HW-7-1 ac power supply has an additional ferrite donut with windings to filter the power, and an additional polarized dc power connection.
Last Updated: May 29, 2007