Note
The UT-1 was developed for use with the MT-1 and MR-1 (Cheyenne/Comanche) mobile rigs as a means of providing for their use from 120 VAC. It is also the forerunner of the HP series power supplies.
The supply is fully solid-state and employs “high capacity filters for less that 1% AC ripple.” The unit provides 12.6 volts at 4 amps OR 6.3 volts at 8 amps for filaments as well as 600 volts at 250 ma, OR 600 volts at 200 ma AND 300 volts at 100 ma.
The filament and HV output options are all chosen during construction and are hard wired. Housed in a louvered steel cabinet in two-tone Heath green. Sports the 3D Heath script logo, an on/off switch, and a pilot light. The rear panel has an six pin socket for power out. Outwardly the UT-1 is nearly identical to the HP-20. The only difference between the two is the addition of a –130 volt bias supply on the HP-20. Its short production life makes the UT-1 harder to find than the HP-20 and 23 series supplies, especially in nice condition.
Replaced by the HP-20 in 1961.
Total DC output power:
150 watts: 600 VDC at 250 mA
OR
150 watts: 600 VDC at 200 mA AND 300 VDC at 100 mA
Filament power: 6.3 VAC at 8 amps, or 12.6 volts at 4 amps
Regulation (50% to 100% load, from high tap): about 10%
Ripple: less than 1%
Power requirements: 120 VAC, 50/60 Hz, 200 watts
Photos, general information and specifications from "Heathkit: A Guide to the Amateur Radio Products," by Chuck Penson, WA7ZZE. Used with permission.
