I was a GCA radar tech in the RCAF in the 1960s and in one of the excercises
(war games) we had to find and fix a fault so the incoming aircraft
wouldn't crash, it was zero visibility . Sometimes it was as easy as a bad
or loose tube, but some seargents had subchassis with cold solder joints,
shorted black beauty capacitors or fried resistors. Time was critcal as the
weather was closing fast and the aircraft was low on fuel. Sometimes the
excercise left us without many parts, partially functional test equpt, and
only partial manuals. To better simulate battle conditions, one end of the
hut could be on fire and CO2 smoke to hinder visibilty! A shorted .01 uF
400VDC black beauty was easliy replaced with a .01 uF 600VDC or .02 a fried
22K 1/2 watt with a 22K 2 watt or something close. Color codes were quite
useful in many cases. The objective was to save the aircraft using limited
resources. Today I don't think we see component level repair in the field
but in battle anything may be necessary for survival. I'd much rather have
something with component values rather than a bunch of codes that required
decifering. I still contend this is a result of "military intelligence."
And the codes make it tough on us hobbyists but we not under a critical time
crunch and with the Internet it's usually a piece of cake.
73
Hank WD5JFR
"Roy Lewallen" wrote in message
...
Jim Adney wrote:
. . .
So I still don't think it's too much to ask that the most important
data be printed out separately.

Obviously, I don't tend to think like the military....

-
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Jim Adney
Madison, WI 53711 USA
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While you've got a legitimate point, you've got to realize the function
of the part number. If you're a technician servicing a piece of military
gear, you replace a 20035942 *ONLY* with a 20035942, not *ANY* other
capacitor, regardless of its value. To order a replacement, you put in a
requisition for a 20035942. Now, it's vital to you that the capacitors
in the stock bin or coming in from the supply system have 20035942
printed on them, but it's not important that the value is. The
technician can find the value in the parts list in the manual and likely
on the schematic. The stark fact is that the military supply system
wasn't created and isn't maintained for the convenience of the ham who's
working on surplus gear.

You'll actually find this is true throughout the industry, with many
ICs, for example, having only the customer's part numbers on them. Go to
a flea market anywhere around here where I live, and you'll find lots of
components with only Tektronix part numbers on them. You'll also find
lots of folks locally who can tell you what they are, at least
generically. I'm sure the same thing is true for HP and Palo Alto,
Motorola and Phoenix, and so forth.

It's not that you don't think like the military -- it's just that when
they developed their stock system they didn't take into consideration
the inconvenience it would cause you, me, and other hobbyists.

Roy Lewallen, W7EL