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Old December 15th 04, 11:44 AM
N2EY
 
Posts: n/a
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In article . net, robert casey
writes:

A big reason for SSB is that, in a pile up, the
receiving station can make out people's voices
without carrier heterodyne whistles.


Not just in a pileup, either.

Also no
wasted power transmitting carriers. Take a
listen to a crouded CB channel sometime and hear
all those heterodyne whistles.


I'll take your word for it ;-)

The biggest reasons for SSB displacing AM on the ham bands, IMHO, a

1) Allows more simultaneous QSOs in a given amount of spectrum
2) Greater "talk power" from a given rig (all the power is in the sidebands on
SSB vs. ~2/3 of it in the carrier on AM)
3) High power SSB can be less expensive to build and operate than high power
AM.

RTTY: 1.5%
FM/NBFM: 0.3%

NBFM might have been better than SSB except it's
wider bandwidth...


No, NBFM was even worse than AM in terms of "talk power". At the narrow
deviations allowed for hams below 29 MHz, an NBFM transmitter was roughly
equivalent to an AM transmitter running one-fourth the power. OTOH heterodynes
were much reduced - capture effect meant you heard the strongest signal and
little else.

Other modes: 0.6%

VHF/UHF (all modes): 12.1%


Even back then, half the hams perferred voice
(phone) modes (AM, SSB, FM). Compared to a bit
over 1/3 perferring CW.


Yep - despite the fact that in those days the spectrum available for US hams to
use HF 'phone was much less than today. And the rig-cost differential was much
greater. No WARC bands back then, and 160 wasn't included in the survey.

It should be remembered that in 1961:

- only ~8 years had passed since Generals and Conditionals got access to HF
'phone on the ham bands between 2 and 25 MHz

- only ~7 years had passed since 'phone was allowed on 40 meters, and 15 meters
was opened to hams

- there were less than a quarter million US hams

- VHF/UHF repeaters were almost unknown on the ham bands. RTTY meant an
electromechanical teleprinter in the shack, whose cost new exceeded the cost of
many hams' entire stations.

It would be interesting to see how the mode and band use would break down
today.

73 de Jim, N2EY