RadioBanter - View Single Post

August 25th 04, 11:07 PM

In article ,
(Steve Robeson, K4CAP) writes:

(Len Over 21) wrote in message
...
In article ,
(Steve Robeson, K4CAP) writes:

(Len Over 21) wrote in message
...
In article ,

More than you. By a mile. You were nothing more than a radio
mechanic.

That's ALL the evidence you have ever provided this forum. YOU were
NEVER
a
"military radio operator".

NOT "mechanic," Diminutive Man.

Fixed station operations and maintenance supervisor.

But never a radio OPERATOR.

Yes, I was. QSYing a transmitter and making sure it stays on
frequency is OPERATING.

Oh, Cool.

You reached up and changed the channel.

WRONG!

Frequency synthesizers enabling channel-changing with ease did
not appear until the 1960s. [the first of which were the stepped
two-crystal-oscillator-bank mixed types for civil aviation] The
exact-frequency synthesizers for fixed-point HF broadcast did not
appear until about 1964.

A QSY at any ACAN station of the 1950s would involve at least 3
persons, two at a transmitter site, one at a receiver site using a
General Radio LF to HF precision frequency measuring instrument.
At ADA, Control at Chuo Kogyo (just outside of Camp Drake) would
issue the QSY order over the TTY order wire; both transmitters and
frequency standards at Receivers were on that loop. Receivers
"freq standards" would begin setting up for the new carrier frequency.

At transmitters, one operator disable the appropriate exciter, then
would go behind the many racks of exciters (O-5s at that time) and
get a crystal from the heated crystal cabinet (6 foot high, glass doors),
change the crystal in the exciter from the back. ADA did their own
crystal finishing. Frequencies were all given code names, for
nemonic convenience not secrecy...avoided accidental transposition
of numbers. Korean circuit frequency names were all given beer
brands...:-)

The other person at transmitters (if only for a 1 KW Tx, the big
PW-15s usually took two operators for safety) would key off the
separate transmitter, reset the adjustments to a chart (prepared by
maintenance specialists on the team), wait for the exciter man to
finish with his task. When RF was getting to the Tx, the Tx man
would tweak-tune the settings, paying close attention to neutralizing
the final (BC-339s had push-pull triode 833s in PA) in addition to
making sure the loading was good.

By that time, freq standards was set up and their freq meter's audio
would be fed into a reserved telephone circuit pair to transmitters.
We could hear it on the speakers. The trick chief would ask Control
for "fox test" on the TTY circuit ("The quick brown fox...etc." from one
of three such automatic cam-driven generators at Carriers in Chuo
Kogyo. Exciter man would zero beat on the Mark, engage keying
and set the "spread" (shift) in a double heterodyne of comparing the
850 cycle tone from Stds with a transmitter tone generator fixed at
850 cycles. Once that was set (all around the console could hear it)
the trick chief signalled over the order wire for Stds to check it.

Frequency Standards would do their final measure and report the
Mark and Space frequencies (if within tolerance) on the order wire
TTY. If something was drifting or the measures were out of tolerance,
Stds reported that, too, and we would have to tweak the exciter all
over again. [accepted RTTY spread back then was 850 Hz]

Maximum time to QSY for RF out at transmitters was under 2 minutes.
Total QSY time, including the Stds measurement and reporting, was
under 3 minutes. That included the large PW-15s (15 KW conservative
output) that had two 3-foot long copper segmented shorting bars (with
two long tightening screws) which "tapped" the huge final tank coil
windings.

The old pre-WW2 Western Electric SSB (12 KHz wide in the
"commercial" sideband arrangement containing four 3 KHz voice
bandwidth channels) was quite fussy and might take an extra
minute or two, including extra time at Stds to confirm frequencies.
The new Western Electric LD-T2 SSB was much better (one in
1953, four more arrived in 1955) in that 12 tuned circuits were all
servo-motor controlled from a bank of 120 potentiometers inside
that were preset to 10 "channels" or authorized carrier frequencies.
The LD-T2 was QSYed by walking up to it, operating two key
switches to disable output and modulation, pushing a "channel"
selector button, then waiting until the indicator light showed auto-
tuning was correct. Then the two key switches were returned to
normal transmit and the RF current meter on the antenna lines
checked. Took less than a minute to do that, took Stds a bit
longer to confirm the correct carrier frequency (pilot carrier in
mid-sideband).

THAT took skill.

It did for the SSB transmitters, including the LD-T2. Maintenance
on the teams had to reset the preset pots if a new frequency was
authorized. That required the same tuning-up was with a manual-
control Tx. The difference between that and the RTTY transmitters
was the requirement to check the audio quality for both level and
distortion.

The objective was MINIMUM DOWN TIME so as to keep the up-time
for actual message transmissions maximum. A typical SSB radio
circuit carried a voice order-wire channel, an overseas radiotelephone
voice channel, and 8 to 12 TTY channels, all on the same transmitter.
At least four of the RTTY radio circuits had time-multiplexed TTY to
carry up to four TTY channels; outage on one of those circuits was
multiplied four time.

HF comms across Pacific would routinely do about 3 QSYs per
24 hour period. With at least 30 transmitters on-circuit 24/7 that
meant at least 10 QSYs per shift.

Ahhhhh...You changed the channel three times a day.

WRONG. I wrote TEN times per shift...on the average. We would
do at least 8 on a calm-ionosphere work shift but could do as many
as 18 QSYs if the ionosphere was doing nonsense.

At the old transmitter site on Tsukushima, commercial Japanese
power was primary. That power was not consistent and any shift
might have to do a full recheck after cutting over to standby
generators (400 KWe minimum out of six motor-generator sets).
That meant EVERYTHING that was on-circuit had to be checked,
including poor Frequency Standards having to juggle their General
Radio instrument controls for every single radio circuit and reporting
it on the order-wire. The new site at Kashiwa (later renamed Camp
Tomlinson) had 600 KWe 24/7 motor-generators and did not rely on
Japanese electric power.

Oooooooohhhhhhhh...NOW I am IMPRESSED!

You should be, but then you've never been tasked with that sort of
job. It's easy for you push-button black-box changers to make fun
of manual control over nearly everything.

ADA did have "VFO" control through a couple of Northern Electric
tunable exciters, but nearly all the HF radios were crystal controlled,
TTY through SSB. The microwave radio relay terminals (arriving late
1954) were all crystal controlled at 1.8 GHz (!). Predecessors to the
uWave were TRC-1 VHF radio relay (FM, both Rx and Tx crystalled)
and TRC-8 UHF radio relay (FM, Tx crystal, Rx manually tuned).

Land forces HT radio, PRC-6, was crystal-controlled, no channel
changing possible. The backpack PRC-8 through -10, was actually
"VFO" on low VHF, manually tuned via a built-in crystal harmonic
calibrator. Surprisingly, the "PRC-8 family" was stable as well as
rugged, holding its locked manually-tuned frequency within spec.

But never a radio OPERATOR.

Yell-yell WRONGO again. See above.

Uh huh...So impressive...Changed the channel on the presets.

Only on the single WE LD-T2...but then I had to set up those presets
from the beginning. :-) The other 35 transmitters (besides the 8 that
were installed later, the new LD-T2 and the 40 KW Collins linear
amplifiers, all preset pretuned) were MANUAL tuning 7-foot high
transmitters.

A single Collins 1 KW Autotune transmitter was there for about a half
year, but used only for the FEC Commander's aircraft. That was
"traded" (?) with the USAF for a couple Wilcox HF transmitters with
the old brute-force AM power amps. The Wilcox Tx was interesting
in that it had 3 separate HF boxes, selectable by a switch. While
that might be taken as "channelization" those were fussy beasts and
had to be constantly checked if up; ADA later sent the RF part back
to the depot, keeping the big AM power amp and supply, marrying it
with a 1 KW BC-339 CW transmitter now becoming a 1 KW AM
radio circuit. That worked just fine and could also (like the lower
power truck mounted HF field radio) carry simultaneous TTY via
an FSK exciter.

Except for the post-WW2 WE Tx, GE microwave terminals, and
Northern Electric exciters, almost all of the equipment we used at
ADA was made on contract during WW2. That includes the VHF
and UHF radio relay equipment used when phone cables went
down. The two ancient WE SSB transmitters were built prior to
WW2. All tubes, nearly all manually operated.

Try again, Sir Putzy.

Rest of usual muck and mayhem deleted. You started off stupid
and got worse (if that's possible)

Tsk, tsk, tsk. I see that there's no possibily of your replying in a
"civil discourse" manner.

You continue to make fun of something you know absolutely nothing
of and won't take the trouble to find out. Not good.

NURSIE is SPOILED by modern, solid-state, frequency-synthesized
tune to any frequency with crystal stability ham equipment...and fine
military airborne equipment she never once had any responsibility for
designing or proving. Tsk.