ARF1 Power Amplifier Repair
- Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
The amplifier is a grounded grid triode tube pair connected in a push-pull manner. As with most all tubes, there is an input and output circuit. The input circuit consists of a coaxial coil made to offer 50-Ohm impedance at 52.8Mhz. This is a broadband circuit (beyond 40 to 60 MHz.). It is DC isolated from ground, (RF grounded thru two 1000pf capacitors) and the filament and bias voltage is applied at the RF grounded end of the coil. The input RF drive signal is developed across the parallel combination of this coil and the tube input characteristics. The bias is applied to the floating filament supply (10V 100A) and clamped approximately at 80Volts thru a stack of forward biased power diodes. (DWG 8000-EB-119592 Located, AP50 rack B55R02). A keep-alive forward biasing voltage is supplied from a Kikusui power supply (located B55R02). The entire amount of DC tube current will go thru these diodes. The RF drive source is supplied from a single ended grounded grid triode amplifier DWG 8000-EC-119605. Since we require a push-pull drive signal, a 180-degree power splitter is used. This is a Fermilab built device (DWG 8000-EB-119604). The circuitry is within an oil-filled container located at the front center of the power amplifier. Shunt variable capacitors and special length input (aprox.5ns) and output (1ns) cables are used for tuning.
- Research Organization:
- Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), High Energy Physics (HEP)
- DOE Contract Number:
- AC02-07CH11359
- OSTI ID:
- 1985133
- Report Number(s):
- FERMILAB-PBAR-NOTE--691; oai:inspirehep.net:864169
- Country of Publication:
- United States
- Language:
- English
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