Hi Andy and Richard, will be almost impossible. Our cave radio experience certainly supports that. The geological maps will give you the underlying rock type, but overlaying it you often have an unkn
Hi Mal, Sorry for the delay in replying. The front panel says "Wavemeter class D. No 1 Mk 2/1". It's in a green metal case about 19x18x15 cms with a hinged lid. 73, Chris G4OKW
Dear James and others, Thanks for your very interesting post. A couple of comments. antenna over a paved area, or on rocky ground, I tried laying it on the concrete driveway: The mesh might not be as
Dear Andy and others, Quite possibly, yes. Bear in mind that - If the IEEE (ex IRE) sued you, would we be talking about US law, English law, International law or some (unholy?) mixture? [Remind me to
Hi Mal, g3kev With the capacitance to earth measured in Jars. 73, Chris G4OKW -- Dr Chris Trayner School of Electronic & Electrical Engineering, The University of Leeds, Leeds LS2 9JT, United Kingdom
Dear Markus, Lawrence and others, Thanks for your interesting comments on this theme. I think I can hear two effects which might be described as phasing. One is due to the different GRIs (Group Repet
Hi Rik and others, Thanks for your contribution. "Ground loss" at my QTH: 500kHz = 35 Ohm 137kHz = 130 Ohm Do you mean resistance in the strict sense, i.e. the resistive component of impedance; or in
The feed wires would keep getting snapped as the winds can be a bit fierce in Cook Strait. :-) Well, then: you have automatically generated QRSSSS weather forecasts. 73, Chris G4OKW
Dear All, There was some discussion on this group a while ago about GPS jamming tests, and many of us have an interest in Loran. There is an item on the BBC news site: http://news.bbc.co.uk/1/hi/sci/
Hi Jean-Louis and others, If this interests you, there's another book on the same subject: Listening In, by Ernest H. Hinrichs, 148 pp., pub. White Mane Books, Shippensburg, PA, USA (1996). Hinrichs
Dear All, John Rabson, F5VLF, is having trouble posting to this group. He asked me to forward this for him, which he has sent unsuccessfully twice: -- Clank, The reflector has twice not delivered the
Hi Mal, a helicopter for an hour or so to support the antenna at several hundred feet high, move the helicopter up and down for resonance !! I like it! Or think big: fasten a wire between your garden
Dear Horst, Thanks for your post. Such earth-loop antennas are more or less standard for cave radio. (AFAIK, this started when Rob Gill G8DSU decided to try them at a Cave Radio and Electronics Group
Mal and others, Silver does tarnish with time and it's not just cosmetic. We have a couple of LCR meters at work with sliding contacts to take the leads of the components. After some years (probably
Hi Rik, I think you'll find it's the H field that goes as the inverse 3rd power. The voltage in the Rx ant is proportional to this, and the power is proportional to the square of that. Thus the power
Hi Hugh, Thanks for the question - it's an excuse not to settle down to the marking again ;-) The energy of a photon is E = h f where h is Planck's constant, 6.626 . 10^-34 Js and f is frequency, Hz.
