1220-A
The General Radio 1220-A Unit Klystron Oscillator was introduced in Catalog O (1956) and remained available through Catalog S (1965).
The Type 1220-A is the foundation of for the Unit Klystron Oscillator series and supplied without a Klystron. It contains all fixtures to adapt the various Klystron tubes, all that's required to change the frequency range is the appropriate Klystron tube. An internal 1 kHz oscillator followed by a Schmitt trigger provides internal square-wave modulation. The 1220-A requires an external power supply, the 1201-B is recommended. The external supply can't supply all the voltages required by Klystron so an internal supply is needed. The internal supply uses 6.3 V ac from the 1201-B to develop the regulated Repeller voltage and unregulated voltage for Schmitt trigger circuit. The front panel accepts external modulation selected by the modulation switch as required.
Specifications
- Frequency Range: Depends upon klystron tube used (refer to table below).
- Modulation Internal: Internal 1 kHz square wave, adjustable within +15 Hz.
- Modulation External: External square wave, 50 Hz to 200 kHz; sine or square-wave modulating signal of at least 15 V rms required.
- Modulation FM: at least 15 MHz excursion obtainable with less than 3 dB change in output; at 60 Hz, on rms input of about 10 V is suitable.
| Type | Frequency Range | Tube | Output mW |
|---|---|---|---|
| 1220-A1 | 2700-2960 MHz | 726-C | 100 |
| 1220-A2 | 2950-3275 MHz | 6043 | 90 |
| 1220-A3 | 3400-3960 MHz | 2K29 | 90 |
| 1220-A4 | 3840-4460 MHz | 2K56 | 75 |
| 1220-A5 | 4240-4910 MHz | 2K22 | 100 |
| 1220-A6 | 5100-5900 MHz | 6115 | 80 |
| 1220-A7 | 5925-6450 MHz | QK404 | 100 |
| 1220-A8 | 6200-7425 MHz | 5976 | 90 |
