On Sun, 20 Oct 2002 20:25:56 +1300, Brenda Hayes <[email protected]>
wrote:
I use my IC706 as signal source for the 180 KHz transmitter, dividing by
100 from the 18 Mhz band - and it works like a charm {our ZL band is
165-190 kHz}.
At some stage I believe that our allocation will be extended to include the
136/137 region and would like to use this same divide by 100 scheme,
starting in the 13.6 Mhz region. My problem is that the 706 will not
transmit below 13.9 MHz.
Do you have a CB band over there that spans at least some frequencies
in the 27.140 .. 27.560 MHz range ?
You could then use an old CB transmitter and add a divide by two stage
to your current divide by 100 divider chain. With 10 kHz channel
spacing on the CB side, discrete frequencies at every 50 Hz could be
generated on the 135 kHz band.
While the spectral impurity of free running or PLL VCOs running in the
upper HF or lower VHF range as used in many general coverage LF/MF/HF
_receivers_ may make the reception of QRSS impossible, since the
frequency deviation of the oscillator spurious signals are directly
added to the received signal.
However, if a transmitter signal is divided down by 200, the frequency
deviation will also be divided by 200, so a 2 Hz spurious deviation at
27 MHz is 0.01 Hz at 135 kHz.
Paul OH3LWR
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