[Lowfer] Alphas

[Douglas D. Williams]

Was able to hear one or more Alpha stations just now on 14.88 kHz.
Previously, I had simply been using the computer's sound card as the
receiver, with Spectrum Lab to give me a visual aid. I decided to try to
actually hear the signal with my R75 + LF Converter. Even with the preamps
turned off, the static level around 15kHz was S9, but with my 250Hz CW
filter in place, I was able to hear the Alpha "bleeps". Switching back to
the sound card as the receiver, and with the microphone input gain turned
almost to max, I finally saw some indication on the Spectrum Lab display of
the Alpha "bleeps" at 14.88 kHz.

What does this tell me? Well, for one thing it tells me that the
R75+converter has more sensitivity than the sound card, at least around 15
kHz.

Why do I care? Well, I was hoping to try to receive one of the "dreamer's
band" 8.97 kHz signals that several European amateurs are experimenting
with. Unfortunately, even with the OCXOs, I doubt the R75+Converter combo
will  be stable enough for the QRSS 6000(!) that they seem to be using.
What most successful receptions seem to utilize is using a computer sound
card as the receiver, and stability is achieved through "locking" the
receiver to a military MSK station. Spectrum Lab has the capability (if you
can figure it out), and I have successfully locked mine to NAA on 24 kHz,
which seems to be the only MSK signal strong enough at my QTH to achieve
the lock. I just hope my sound card has sufficient sensitivity.

On another note, as I sit here typing this I am listening to my Z1501
active antenna connected through a 50 kHz low pass filter then plugged into
the computer's sound card. I had Jack (owner of Clifton Labs) modify this
one so that the VLF sensitivity is increased down to around 3 kHz. This
makes it a fairly decent natural radio receiver for use at home, though you
lose the low end compared to, say an RS4 or a WR3. Right now I'm hearing
plenty of "bacon frying" and the occasional tweek. It's very nice to sit in
the comfort of your office with a cup of coffee and listen to "nature's
radio" instead of out at some remote location shivering in the cold. ;-)
Jack's design of the indoor Z1203 power coupler isolates the receiver and
station ground from the coax fed out to the antenna, which prevents all
kinds of crud from being carried along the coax shield to the antenna. If I
were to connect the Z1203 coupler to station ground, I would immediately
hear nothing but a strong buzzing noise on my headphones. Nice job, Jack!

Doug KB4OER