Hi Gary, Roelof, Group,
Your grabber is used a lot here, Gary. Thanks for keeping it going
and congrats on the daytime reception. And as of 2108 Roelof's
grabber is showing clear sigs. Thanks!
From 1922 to 2007 utc the LF TX took a break for the VLF TX on 8277 Hz.
Yesterday an old XR2206 was discovered in the shack and it seemed
this might make a nice LO for a DC RX. A 4066 was used as a mixer
and an LM386 as the audio stage. The PA0RDT MW fed the mixer. A
crude design for sure, not even a diplexer to follow the mixer so the
8730 Hz LO was qite loud in the speaker. It was a lovely sunny
but cold day so I put the contraption against my ear held the MW
above my head with the other hand and began walking. The VLF CW
beacon could be clearly heard at 0.5 km but disappeared at 0.7 km.
There were all sorts of strange noises heard including the Alphas
For TX, about 10 watts were fed to a 1:4 xfmr and tuned to
the 100m wire (15m mean height) with about 0.35 H of very lossy
inductance.
DL4YHF Spectrum Lab in the DC RX mode was used in earlier experiments but
it seems the computer makes much QRM. For todays test, I took the
computer battery pack to power the RX and left the noisy part the shack.
This the best VLF DX so far from here. It is hoped to get a few km of
wire for an improved tuning coil.
73
Joe VO1NA
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