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E-611
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überarbeitet am 1.6.2013 |
The receiver Hallicrafters SX-23 with it's outstanding art deco design seems to have seen use with the Swiss Army, the purpose of use is unknown to me.
The SX-23 has a 48 x 23,5 x 31,8 cm metal cabinet, it's hinged lid gives access to the chassis for valve replacement. The Super Skyrider SX-23 has a quite unique art deco cabinet not seen with any other Hallicrafters sets. In contrast to earlier receivers made by Hallicrafters, it does not come with a engraved metal disk dial mounted in front of the front panel but with a metal dial rotating behind a sector shaped dial window, two smaller windows show a mechanical band indicator and the signal strength meter. In contrast to later models, the dial is not of the transparent backlit type. Below the main frequency dial, you find the the band selector with markings for the four ham bands and four "General coverage" bands: 540 kHz - 1,7 MHz, 1,7 - 5,2 MHz, 5,2 - 16,5 and
16,5 - 34 MHz. The "steering wheel" main tuning knob is replaced by one with a fine tuning gear in my example of the receiver. I logging dial and calibration chart can be use to re-tune a known frequency in the bandspread frequency bands. The RF signal coming from the antenna input is amplified in a RF amplifier stage (6SK7) and fed to the mixer stage (6SA7) to generate an intermediate frequency of 455 kHz; a 6SJ7 valve ist used in the local oscillator. After two IF amplifier stages (6SK7, 6SK7), the signal is demodulated (6SQ7) and fed to the audio preamplifier and final amplifier (6F6). The BFO (6SJ7) is used for CW and single side band signal reception. A 6B8 is used for A.V.C., the double diode 6H6 in the noise limiter. The eleventh valve is the two way rectifier valve 80. There are no informations available about the purpose of use of the E-611 / Hallicrafters SX-23, it probably has been used for monitoring or signal's intelligence. weitere Lektüre: © Martin Bösch 1.5.2013
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