From: "Jim Hampton" on Sun,May 8 2005 4:26 pm

wrote in message
oups.com...
From: bb on May 7, 9:38 pm

K4YZ wrote:
bb wrote:
wrote:

would be something about ham radio style "operating." :-) The
United States military communications groups are PROFESSIONAL
in all aspects, not amateur radio hobbyists. shrug

It just might be what a particular operator is familiar with. Back
when (in
the 60s) the military used a lot of HF point to point communications,
they
(the radiomen) were familiar with having to change frequencies, how to
set
crypto gear, and many other things. One thing they were *not*
familiar with
was how to handle a strong signal.

[heh...I could see what was coming before reading further]

When the communications station attempted to re-establish
communications
with Saipan, Hans, K0HB, was sent to Saipan. The communications
station
kept telling him he was "loud, but garbled". Big hint - too much
signal for
the local oscillator injection to properly demodulate the ssb. I
called
Hans from the hamshack (KG6AAY) and we (the hams) ended up not only
establishing communications but got orders to pass traffic from Saipan
to
Commander, Naval Forces Marianas directly.

So...an anecdote from USN days is suddenly a Standard
Operating Procedure? Or a professional dissertation on
how certain others are "completely 'wrong'?" :-)

Two things, perhaps three, come to mind here.

First of all, the HF military receivers of the 60s era,
typified by the R-388s and R-390s, all had RF GAIN
controls. NOT a problem to handle the alleged "overloads"
of strong signal length. There are ADDITIONAL controls
for attenuation, not only on the receivers but on their
outboard Converters for TTY or SSB separation. Were
all the "S Meters" on those receivers inoperative?

Secondly, a transmitter could have been deliberately
mistuned (without damage to itself) to reduce the
signal power output. Non-standard, but that would have
been a possibility...such as toss a wire out the window
(porthole?) and tune that up. :-)

Third, how did YOU "know" the garble WAS "intermodulation
distortion" if you didn't have any way of determining
the incoming signal strength? I'm familiar with the
characteristics of U.S. military receivers of the 60s
(through testing to spec. and for other, specialized
applications)...and those have a rather wide dynamic
signal strength range with or without the deliberate
attenuation via RF GAIN setting.

I also recall whilst aboard ship we lost the "broadcast" - multiplex
signals
for many channels of teletypes.

Sounds like the common "commercial format" SSB that's
been around since the 30s...12 KHz wide modulation
spectrum, the outer 6 KHz carrying 4 to 12 TTY tone
pairs. One needs the Converters (outboard) to
separate them and all the Converters I've seen all
have separate level-setting controls...as do the
"carrier" equipments that separate out the individual
TTY signals.

The problem was that we were getting to
close to the station and we were in a skip zone. I suggested to the
chief
that we try LF (low frequency). He didn't think it would work, but
said to
give it a try as everything else was out. On LF, the signal was
overpowering. In a few minutes, the broadcast was back up and
running.

What are you saying there? Are you saying that LF
is "immune" from IM effects? [ain't so...]

The USN was running 12 KHz SSB on LF? Capable of it?
Doesn't sound likely. Please explain.

In both of these instances, it was the hams that had the proper
experience.

"Proper?" :-)

Your tale, oriented for the "lets all give each other high-
fives as hams for saving the world again" crowd in here is
a nice story. But, without some revealing details, it seems
little more than a STORY.

In that same era, in the USA, it was not uncommon
to have Field Radio AN/GRC-26 huts-and-trucks at
sites as close as 15 miles. They never had any
reported "overload to the point of garble" on their
single-channel TTY with AM voice communications
locally. "Angry-twenty-six" was typically 400 W
(CW) output carrying dipole and half-rhombic wire
antennas, using either R-388 or R-390 receivers.

Could it be - gasp, choke - that the Army guys
were "better" at communications than you sailors? :-)

I shan't go much further than to say that one day whilst aboard ship,
we
received an SOS on 500 KHz. It turns out that only *two* of us could
actually copy Morse at any reasonable speed. I don't know about the
other
guy, but I was an amateur extra and also had a commercial telegraph
license.
The military radioman were *supposed* to be able to copy 16 words per
minute
to graduate from A school.

There ya go! Another tale of "hams make the world
safe and show the pros how to do it via CW." :-)

Ho hum.

Why is it that the ENTIRE maritime world of radio
REJECTED morse code messaging for distress and
safety in favor of GMDSS? Tsk. I've heard all the
tales of "GMDSS won't work!" from all the retired
navy morsemen...but GMDSS continues to work...with
the approval of the maritime community. Tsk.

Field Radio MOSs in the Army of the 60s era ALSO
had to demonstrate morsemanship. Ho hum. The
Army field commanders insisted on using TTY
messaging just the same. There's NO need to
demonstrate morsemanship in ANY branches' radio
communications specialties today. NONE.

Sorry to shoot your "professional" theory down.

Just WHO were you aiming at? Wasn't me. I wasn't
hit by any "fire." :-)

Your airborne "spotter" must have been that TN CAP
ace, Stebie Robeson, former "ANCOIC" of Okinawa
MARS and PR Field Agent for ARRL recruiting. :-)

HE should have his wings clipped.

You aren't totally wrong,
of course; it is what happens when the *unexpected* happens.

Tsk, tsk, tsk. Us ex-Army types just never had
"emergencies" or "weren't as good as hams?" :-)

Best you hike on down to the nearest office of
BuShips or whatever and inform THEM that they
are "all wrong" or even "partly wrong" and
re-insitute all that morsemanship training (to
keep the world safe through use of Sam's wonderful
code). Think of it as a "holy mission."

Peace be unto you. Amen.