Offering a near mint Drake L4B (one of two electrically identical units
available) 10-80m linear amplifier retrofitted with a brand new Eimac
8877. From the exterior, this deck appears stock Drake except the CW/SSB
switch position has been eliminated. The two part switch has been pinned
and operates as a DPST power on/off control. Major modifications have
been made internally to handle 1700W OUTPUT on 80m* and 2200W OUTPUT on
ALL other bands. The deck has been upgraded with the correctly rated
filament transformer, filament voltage monitoring pin outs, custom heavy
duty HV porcelain plate choke, solid state delay timer, mica input
tuning capacitors, high speed blower, porcelain grid to ground air
system socket, Teflon chimney, and a parasitic choke assembly for
trouble free tuning. The small footprint power supply has been custom
built around a brand new Peter Dahl Hipersil producing 4000VDC @
1/1-1/2amps. The remote (220VAC only) power supply is separately
metered for voltage and current, has a step start circuit with heavy
duty contactors, and is fan cooled. A front panel power supply switch
allows for half power operation (1800-2000VDC) and a second bucking
voltage switch provides and an additional 400VDC totaling 4000VDC.
Maximun output power was measured with a Bird 43 and a 2500H slug with
235-240VAC on the primaries. * The bandswitch assembly was unaltered and
used as per Drake. Apparently, a minor 80m coil tap change may be in
order to increase the power. Sorry will not ship! Pick up in the
Scranton PA, New York City, New Jersey (GSP exit 117) areas or I
anticipate being at Timonium and Dayton. Take a look at the Yahoo site
for a complete array of project digitals. $1850 Ron W2CQM/3
See HTTP://QRZ.COM/W2CQM for the most recently published articles
related to amateur radio. See http://briefcase.yahoo.com/W2CQMron for
amplifier related material. Click on Drake retrofit.
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