On Oct 30, 1:59 pm, clifto wrote:
NM0S wrote:
I'm one of the 4 who submitted an entry to the ARRL HBC contest.

Feel free to brag here in further detail.


OK, don't mind if I do. Basically, my design is a direct-conversion
rig, with a Class-E PA running about 90% efficiency DC-RF (CW anyway),
delivering 5 to 6W PEP. Finals are push-pull 2N7000 MOSFETS, directly
driven by a 74HC86 logic gate. VFO is a PTO covering the full 40M
band. Voice mode is Double-sideband, suppressed carrier. There is
an AGC on the receive, and ALC on transmit, so there is only one
knob, for tuning. The receiver uses the PA MOSFETS as the receive
mixer. The audio amp is discrete transistor design, with automatic
bias control to reduce current consumption when no signals are
received. Total current draw on RX is 30mA, on TX 600mA. There is
a 200 Hz CW filter that is switched in when a key is plugged into the
KEY jack. Total parts cost, including enclosure and PCB is $40. Will
work from 9V with reduced power.

ICs used a LM324, LM3900, LM339, 74HC86 and 78L05

I'll make boards available if there is interest.

73 - Dave NM0S