CCWN 75:51

JA-W6 TEST OF CCW BY CHAS. WOODSON


          On the basis of several hours of tests between JA and W6
of CCW on 14#049,000, I have some informal results to report.

          CW transmission from JR1zZR used a FT-101. CCW transmission
used a Coherent CW transmitter (CCW-1) which will be described
later in CCWN. The antenna is a verticle dipole on a
four-storv buildinq. A homemade 10 db sad was used.

          Most reception was by a verticle groundplane on a house
roof at W6NEY. The receiver was a SB-303 with Petit filter
for CCW. Some tests were made from W6BB using a 3-element
20 meter beam and the receiver from W6NEY. Signals seemed
a bit stronger, but we do not have sufficient data to say
whether that was due to band conditions or antenna. Generally
I would expect the beam to be a bit better.

   Rotations among four conditions were made for comparisons.
   
    1. 10 watts Cwr received with 2.1 kHz filter
    2. 10 watts CW, received with .5 kHz filter
   
   3. 1 watt CCW, received with Petit filter
   
   4. .1 watt CCW, received with Petit filter
   
   Some subjective conclusions:
   
          1. For CW, the .5 filter was clearly better than the 2.1 kHz
in both QRM reiection and sensitivity.

          2. At times the 1 watt CCW seemed considerably stronger than
the 10 watt CW siqnal.

          3. The .1 watt CCW signal was about the same or a bit better
than the 10 watt CW signal.

          4. Little QRM was experienced on CCW. QRM caused random
dots, popping or higher noise. QRM seemed to last only briefly,
apparently because the offending station drifted away.

          5. Local QRM sometimes causes noise, apparently this is
in the frount end of the receiver.

          6. Once set, the phase adjustment of CCW is constant over
the QSO. This required no changes after initial adjustment.

          7. CCW operation seems easier. Apparently this is because
frequency and phase are set and no receiver adjustments are
needed during QSO. Perhaps the constant known speed makes
copy easier too.