[SCCC] AM to SSB transition

[Art Goddard]

Wayne, et al,

Collins Radio was at the forefront of SSB, using their Permeability Tuned 
Oscillator (PTO) and mechanical filter technology. Collins published a 
seminal handbook, "Fundamentals of Single Side Band" in 1957, (2nd ed in 
1959)

My earliest recollection of SSB was at Worcester Tech, W1YK, when the club 
station acquired a Central Electronics 20-A exciter about 1961.  I don't 
remember if we tried to drive the club's Globe King 400 with the 20-A, and 
have no idea what the output signal may have sounded like.  Meanwhile, I was 
one of the net control stations for the Western Mass Phone Net and we 
continued to operate on AM.

In the mid-60s, when I took a job at Jansky & Bailey in Thailand, they had a 
KWM-2A and we used SSB for comms between the office in Bangkok and the field 
site near Khao Yai National Park.

Later, as SSB was really taking hold, I was a grad student at Montana State 
and worked with Prof. Donald K Weaver who had patented the third method of 
generating an SSB signal. 
https://en.wikipedia.org/wiki/Single-sideband_modulation.



-----Original Message----- 
From: Wayne Overbeck via SCCC
Sent: Sunday, December 16, 2018 7:58 PM
To: sccc at contesting.com ; Dennis Younker NE6I
Subject: [SCCC] AM to SSB transition

Dennis, I'd really like to see some discussion of the AM-to-SSB transition
here on the SCCC list.  It would be fun to read what others remember from
those days.  Here are some of my recollections.

As a young ham in the 1950s I operated several contests on AM before SSB
became the mainstream voice mode on the HF bands.  The high point for me
was 1959 Phone Sweepstakes.  I finished second in the L.A. section, running
a Heathkit DX-100 transmitter and Hallicrafters SX-101 receiver to a 
2-element
cubical quad for 10 and 15 meters (up 25 feet at the center--not very high 
even
by 1959 standards).  The guy who beat me (W6LNW) was #2 nationally and
he had much bigger antennas than I did.  Size mattered, as it still does.

QST published a list of the equipment used by all of the section leaders in 
those
days.  In 1959 almost all of the winners were running AM transmitters like 
Viking
Valiants, DX-100s or the earlier Viking I and Viking II rigs.  I don't think 
there was
much SSB activity in Phone Sweepstakes until a few years later.  I went off 
to
college and didn't operate SS for several years after 1959.

By 1965, however, everything had changed.  Almost all of the section leaders
were running SSB rigs and operating the contest mainly on SSB.  At the same
time, overall voice activity dramatically increased.  In 1959 Sweepstakes, 
CW
logs outnumbered phone logs by a 3:1 ratio.  By 1965, the ratio of CW logs 
to
phone logs was only 5:4.  There were more phone logs than CW logs in SS for
the first time in 1970, according to the tallies of Ellen White, W1YYM (now 
W1YL),
who wrote most of the SS articles for QST in that era.

Clearly, the transition to SSB led to a major increase in overall voice 
activity in
Sweepstakes.  However, it didn't lead to the kind of increase in overall 
scores
that you might expect.  In 1959, the top phone scores were over 200K (on 
AM),
not that much lower that the top phone scores now, 60 years later.  However,
that's really comparing apples to oranges because there was a power 
multiplier
then.  Also, the maximum operating period on each mode was longer than it is
today.  And to be honest, I don't think anyone worried much about "rubber 
clocking"
until the 1970s.  Most of us didn't operate anywhere near the maximum time 
allowed.

I don't remember the best receivers of the 1950s being that bad.  They had 
good
sensitivity and selectivity on the HF bands, even 10 meters.  What was 
different
was the HETERODYNES on the bands.  With all those AM carriers, during SS the
phone bands were a sea of squeals and whistles.  Receivers had notch 
filters,
but you couldn't eliminate all of the squeals.  (Null one out and another 
one would
pop up.)

Voice operating didn't seem all that different back then--except for the 
awful QRM.
With my DX-100 (about 100 watts of high-level plate modulated AM), I could 
hold
a frequency and run all day on 10 or 15.  S&P was a pain, though.  Without a
transceive mode you had to zero-beat every station that you called.  I very 
much
preferred running--and I hated it when 15 dropped out to the east.  I 
couldn't ever
hold a frequency and run on 40 meters.  W6LNW, the guy who beat me in '59
phone SS, could hold a frequency and run all night on 40.  I spent some 
envious
times listening to him.  Size mattered.  Um, did I say that before?

Just some random memories of phone contesting in 1959...

73, Wayne, N6NB (K6YNB back then)




--------------------------------------------
On Sun, 12/16/18, Dennis Younker NE6I <NE6I at cox.net> wrote:

Subject: Re: [SCCC] Looking For Write Ups, Comments, Observations AM to SSB
To: sccc at contesting.com
Date: Sunday, December 16, 2018, 4:02 PM

Some really good stuff has been
sent along to me for the upcoming article.
Does anyone have any old photos of that time
period? Station photos from the
1950s and
60s would be a great add to the article! As well, your
contest
experience during that time frame
would be interesting. What was it like to
operate a contest where both AM and SSB
co-existed on the bands? Receivers
were so
less capable back then that I can only imagine how
challenging it
was for a few years there.

As before, please reply only
to me so that I can capture your comments and
photos for the article. Thanks!

--Dennis NE6I

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