|Johnson Challenger Transmitter|
|Description||Bandswitched Shortwave Transmitter|
The Johnson Viking Challenger is a single knob bandswitched shortwave transmitter which covers the amateur 80 through 6 meter bands and provides both CW and Phone operation. Crystal or external VFO frequency control is provided by simple front panel plug-in arrangement without switching, The power input rating is 120 watts CW and 70 watts Phone with the input restricted to 85 watts on the 6 meter band. A panel mounted meter monitors plate current (power input) and grid current of the final amplifier. The meter leads and AC line cord utilize individual RF filters to supplement the excellent cabinet shielding and bonding which provides very good suppression of spurious radiation and harmonics and reduces interference to other services. The circuitry employs a 6DS5 crystal oscillator (RF amplifier when driven by a VFO), a 6DQ6/ as an RF buffer-driver, and a pair 6DQ6A's in parallel, bridge-neutralized, as the final power amplifier. A 12AX7 dual triode functions as a two stage speech amplifier to drive a 6AQ5 clamp tube modulator. On CW, the 6AQ5 clamps the final amplifier screens to lirjiit the key-up plate dissipation. A 5U4GB rectifier delivers D,C„ power to all stages.
These manuals are available for the above equipment:
|Johnson -- Challenger -- Service and User Manual|
|Manual Type||Service and User Manual|
|Size||801.73 Kbytes (820975 Bytes)|
|Quality||Scanned document, all readable.|
|Upload date||01 March 2014|
|Downloads||181 since 01 March 2014|
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