2N2/20 -
A 20 Meter, Discrete Component CW Transceiver Built Manhattan-style
Designed
by: Jim Kortge, K8IQY
Summary
The 2N2/20 is the latest incarnation of the rather long list of 2N2/XX designs. Departures from
the all "2N2222 transistor dictate" provided an
opportunity to use a variety of discrete semicondutors to enhance
performance. Within the IF chain, MPSH10 transistors were used, a
J176 FET was used in the audio mute for very clean QSK keying, and
a 2SC2166 final amplifier, used in the transmit strip allows the rig
to put out about 7- watts. Commercial DBMs were also used to make construction
easier for the beginning builder. Another departure from other 2N2/XX
designs was the use of a commercial frequency display (KD1JV product)
to show the operating frequency.This rig features a Norton "Noiseless feedback" RF Amplifier, electronic RF gain control, RIT, 6-poles of crystal filtering with a 500 Hz bandwidth, and 100 KHz of band coverage from a voltage tuned, stable VFO.
The debut of this transceiver was at Pacificon 2004, hosted by NorCal, and held in San Ramon, CA over the October 10th weekend. Slightly updated versions of this presentation were also given at Atlanticon in March, 2005, and again at Ozarkcon in April, 2005. The latest version of the presentation is available in .PDF format on this page, along with other pertinent information about this rigs design, construction, and performance.