Thread: radar questions
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Lynn Coffelt Lynn Coffelt is offline
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Default radar questions


"Bruce in Alaska" wrote in message
...
In article ,
"Lynn Coffelt" wrote:

There were some strange diodes in the klystron tune regulated voltage

source
that were no longer available (this in about maybe 1978). Dumb thing

would
drift out of front panel tuning range periodically. Could bring it right
back with chassis pot, of course, but owner frowned on that and I never

did
get paid! Don't blame him a bit.


The KRA124/248/448 didn't have a Klystron for an LO, but was the first
of the Second Generation Radars, and used an XBand Gun Diode Osc. As
I recall Furuno last used a 2K25 Klystron in the KRA 121 Series Radars
which was before Northen picked up the Furuno Dealership. Don
Hollingsworth Sr. at G & L Marine was the KRA-121 expert and has always
been the "Go To Guy" for Marine Radar Technical Information, even when
he was the Raytheon Marine Tech (Ray 1500/1700/1900) for the NorthWest,
and worked for U.G. Allen.

Man that does date me, in the North Pacific Marine Electronic Community.

Bruce in alaska


That's what I get for letting my mouth overrun my holeridden memory.
The Konel that I was remembering did have a Klystron, and came in an "up" or
"down" transceiver model. The one on the yacht/halibut boat had the "up"
version and I had to make a test cable to run the transceiver in the pilot
house. It would see a mile or two with the waveguide coupler pointed out the
window. Boss insisted on a dummy load when he was around, but that made the
NE-2 on a stick, or echoes from down the bay unavailable. (I think you
mentioned once that "real" technicians didn't bother with the stick)
I guess I didn't get Furuno tech bulletins farmed out to me in
Anacortes until maybe 1979....... isn't that about the time the "toilet
bowl" went from KRA112 to KRA124? (and about the same time as the phenolic
based boards in the display started burning between lands all over the
place? Best troubleshooting was in a dark room, turning off and on, watching
for glow or sparks. Of course it was hard to see smoke then, but you could
smell it pretty quickly.

Old Chief Lynn