Model HF-1 M

photo Gates HF-1 M The HF-1 M Transmitter supplies 1000 watts output power that may be 100% modulated for either communications or broadcast. Powers in excess of 1 KW output are possible when keyed. With high frequency coverage from 2 & 32 mc, coverage between 3 & 32 mc is continuously variable from the front panel, by adjusting dial settings - no component changes necessary. HF-1 M is an all purpose transmitter. All modulation components are of broadcast quality. Where the wide audio range of broadcasting is not desired, the Gates limiter/filter amplifier is added for communication quality. Manual keying up to 60 WPM including break-in may be augmented with an optional electronic keyer for speeds up to 400 WPM.

Heart of the HF-1 M is the M-5239 exciter that accommodates 10 crystals in open holders (0.02% accuracy) or in temperature controlled ovens (.003% accuracy). Completely self-contained including metering, this exciter delivers up to 85 W output to drive the final power amplifier directly. Entire tune-up of the transmitter to the final stage is simple and quick. Select desired crystal frequency, set band change controls to proper frequency range and resonate. Logging for resonance is restricted to only two controls as oscillator is untuned. Has three stages: 5763 oscillator, 5763 amp. doubler and (2) 6146 output. A 6AQ5 screen clamper and 0B2 regulator tube is also employed. Keying or break-in is optional three ways: (1) oscillator cathode only, (2) IPA cathode only, or (3) both.

Continuously variable rotating coils ganged for one dial operation, tune the PA stage from 3-32 mc. Where operation is below 3 Mc a padder is added. For quicker tuning a low power tune-up switch has been incorporated to allow the operator to check exact resonance before applying full power. The HF-1 M uses a single 4-1000A power tube in the final amplifier. This tube rating is actually capable of over 1500 watts output which means long life at 1000 watts.


1. Continuously variable by front panel control 3-32 mc, a padder is added where 2 mc is desired.

2. Audio system either for broadcast or voice. When voice only, use with M-5263 limiter/filter amplifier.

3. Complete relay system for complete protection including (a) fil. on relay, (b) plate on relay, (c) time delay relay, (d) PA overload relay, (e) mod. overload relay and (f) underdrive relay.

4. High level class B modulation with twin-drive audio for full reliability, low distortion and long tube life with 833A modulators.

5. 230 volt, 50 or 60 cycles, single phase operation. Main power supply has 2-section choke filter for superior regulation and low ripple content.

6. Servicing ease and maintenance. Only one cable interconnects the entire transmitter. RF and audio decks instantly removable to clean or service. Blower and suction fan assures excellent cooling of all components.

Power Output 1000 watts, 100% modulated, 2-26 mc. 800 watts, 100% modulated, 26-32 mc
RF Output Impedance 51.5 ohs. Where other output impedances are desired, special coupling units are available to match customer requirements
RF Range 2-32 mc. Continuously variable by front panel tuning. Padder added for 2 mc operation
RF Stability Where used with JKO-2 temp, controlled oven, .003%. Where used with H-7 holder. 0.02%
RF Harmonics Suppression of harmonics meets or exceeds FCC requirements
Audio Frequency Response As broadcast transmitter ±2 db 50-7500 cycles. ±2.5 db 30-10,000 cycles.
As communications transmitter (when used with M-5263 limiter/filter amplifier) ±2.5 db 200-2500 cycles with sharp cut-off above 2500 cycles
Audio Harmonic Distortion 3.5% or less 50-7500 cycles at 95% modulation
Audio Input 10 db ± db as broadcast transmitter.
When used with M-5263 limiter/filter amplifier, input is either low level microphone or 600 ohm line
Audio Input Impedance 150, 250 or 600 ohms
Primary Voltage 230 volts single phase 50/60 cycles
Power Consumption Consumption at 0% modulation or CW, 3200 W. At average modulation, 4500 W
Carrier Shift 3% or less at 100% modulation
Total Number of Tubes 23
Total Tube Types 10
Type of Output Single ended, full Tee network
Number of Crystals Ten crystal positions. Where JKO-2 temperature controlled oven is used.
2 crystals used in each oven.
For non-temperature controlled crystals, up to ten type H-7 crystals and holders may be accommodated.
Crystal switching from front panel
Modulation High level Class B
Weight 1095 lbs. packed, 846 lbs. net. Cubage 97. Export weight 1665 packed. Export cubage, 158.0
Cooling Squirrel cage blower cools final power tube and PA.
Fan in ceiling of transmitter complete circulation thru grill intake at bottom front.
Specifications may change without notice

RF stages AF stages and modulator Rectifiers
Number Type Number Type Number Type
1 4-1000A 2 833A 2 8008
2 6146 4 1622/6L6G 4 5R4GY
2 5763 2 6SN7 1 6AQ5
1 OB2

2 6Y6G


ITU Country
ITU Country