4SQRP Bayou Jumper 40 Meter CW Transceiver, Руководство по сборке и инструкция

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revised 3 Feb 2021 Bayou Jumper revB Assembly Manual page 35 of 46
Design Notes

Tuning range approximately 140 to 160 kHz
– enough to cover the Extra Class CW band
through the old “Novice Band.”

One knob tuning
– no bandset/bandspread needed.

Only one toroid to wind in the receiver section. Etched PCB inductors used in the
transmitter section.

Varactor tuning employing readily available Schottky diodes as varactor diodes.
Regeneration control also employs a “Schottky varactor” as the throttle capacitor.

Use of potentiometers controlling only the DC bias on the varactors for tuning and
regeneration means the controls are not “hot” with RF, so “hand effect” detuning is
minimized.

RF attenuator control, which is useful when employed with full-scale antennas.

Robust headphone audio, and will drive a small speaker with modest volume.

Current drain on receive about 20 to 25 mA, less than 600 mA on transmit at 5 W

Harmonics and spurious down about 50 dB with respect to the fundamental, exceeding
the FCC 43 dBc requirement.