The “Monobander” Series - 20 Meter Phone
I purchased the radio, without power supply for $30 from a craigslist seller.
In addition to the usual well written Heathkit Manual, the rig was accompanied by a collection of update packets. The first of these is well known and is noted everywhere Heathkit Service Bulletins and Mods are documented - it's not titled, but takes the form of a letter "Dear Customer..." and proceeds to give updated component values for HW-12, HW-22 and HW-32, and notes a series of minor component changes to eliminate ground loop effects and other oscillations when the antenna match is higher than 50 O. The sheet for HW-32 is titled "HW-32 Modification". None of the modifications had been done.
However, two additional Packets were included along with the usual HW-32 (-22, -12) mods.
- HWM-32-1 - a somewhat involved modification to shield the Output Finals
- Tri-Bander Conversion Kit - Instructions to enable any of the Monobanders to be modded to work all 3 bands, SSB or CW, Upper or Lower Sideband.
Regarding #1, while the original HW-12, -22, -32 mod kit was a typical modification, this one included a metal RF finals shielding box (actually an inverted shell) which fits over the two 6GE5 tubes. To date, I've not heard or seen written of this modification. Although the instructions were present, the finals cage wasn't installed, and none of the modifications had been done.
Modifications #2 were from an outside ham enthusiast and not from Heathkit. The modifications are extensive and probably non-reversable. It seems that the instruction sheet was 'what you got' and you had to order the parts separately. Fortunately, #2 was also not installed.
Getting It Started...
This rig was impossible to even test, since it was wired for the 8-Pin connector usually found on the HP-10 and HP-13 DC mobile supplies or HP-20 (AC) supplies. So, the first task was to convert the connector to work with the HP-23 supply (A, B, or C), which has the 11-Pin connector. In addition, the main board was wired for the HP-20/HP-10 combination, and a couple of wiring jumps would need to be made to accommodate the voltages on the HP-23 series. After looking up some references, here's the 'translation' I put together between the 8- and 11-Pin power cables:
|-130 VDC Fixed Bias||1||1||Green|
|Common / Ground||2||7||White|
|250/300 VDC Low Supply||3||3||Orange|
|800 VDC High Supply||4||4||Yellow|
|12.6 VAC Filament||6, 7||2, 6||Red, Black|
|AC Power Switch||5, 8||9, 10||Blue, Brown|
|No Connection||11, 8, 5|