May i add a few last words to this topic "miracoleous inven-
tions (antennas) and the follow ups" i forgot in my letter
before:
The design of the Drakes (i name the "4-line", to be honest,
as i never have seen a "7" or it's successors in technical
(schematic) detail) is straightforward and simplicity itself.
O.k., this goes also for design details like the class "A"
final audio amplifier in the R4-C or the very high-impedance
AGC-line in the SPR-4, but there are a lot of reasonable modi-
fication solutions available. Besides the drawing style
of the schematics, everything associated with the working
principle of this gear is relatively easy to understand if
one is familiar with rf and electronics basics.
Nevertheless, this kind of equipment could easily be main-
tained and repaired by hams (and our license implies that
we are allowed to build, modify and repair our equipment by
ourselves) with a minimum of fancy test gear - and: at least
for the semiconductors, there is always one drop in re-
placement available. No "expensive and hard to get" spe-
cial IC's, no "black functional block" in the schematic
nobody understands, no tiny SMD-IC's with 120+ pins where
one needs a magnification glass to distinguish the indi-
vidual pins, no need for costly super-precise signal ge-
nerators, spectrum analyzers, logic test stuff and the
else. Evermore, you remove the top and bottom cover and
have full access to every component while the unit still
is fully operative - no special test cables, no extender
boards or other special stuff that will cost you a for-
tune - nothing.
I have access to lab-grade test gear, however, i did all
the work on my Drakes with a minimum of test equipment
and some phantasy with full success - and i verified
this work with the professional test gear. Result: Every-
thing is meeting the specifications stated in the manuals.
To my knowledge, there is not much more "modern" ham gear
on the market, that could claim the same simplicitiy for
itself.
So long for this topic.
Herbert, DG7MCC
Mike Williams schrieb:
Herbert, well said!
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