For LF I can use either the house ground, which is also connected to the water pipe net, or a radial ground made of 28 insulated litz wires with lengths between 12 meters and 30 meters depending on
I (and others) experienced the same. I think that this increase could be explained by the fact that the 'returning' current coming from the 'radial-earth' and from the 'mains-earth' have different ph
Here is my two cents worth ... done on the fly ... The multiple feedpoints in a multiple tuned antenna give an apparent increase in the real component (resistance) by transformer action (currents div
Rik Strobbe wrote: But what to do with the 'loss resistance' (RL) in the real world ? Assume a simple model where both tuned sections share the same ground-system. In that case RL would be in series
Dave Sergeant wrote: At first I thought much of this loss was due to the series loss resistance of the matching capacitors (Philips 376) but further calculations from the datasheets shows this not to
Hi Des, In his mail Geri, DK8KW, has given a very good description of what to do. I would like just to add 2 options : 1. If it is mechanically possible you might gain some dB's by placing the loadin
Thanks to Dick PA0SE for modelling a range of antenna configurations. Comments are made on excerpts: In this (the last I hope for you ...) report you find the results of computer simulation of a coil
Hi all, Thanks to contributors of comments on receiver performance at LF. Some more points tossed in to the melting pot ... The bandwidth and shape factor of a receiver IF filter is one of the "heart
Peter, I have had a "play" with a TS 850SAT, as a try before buy offer. I can confirm it works better than I would have thought on receiving LF. The circuit diagram shows it has a separate pre-amp fo
Rik ON7YD and others, Here in ZL we have been using wire wound resistors as dummy loads for some years, and they generally work well on frequencies up to 180 kHz. Those types with some residual induc
Hi all, I think I have mentioned some of this previously on this reflector site, but I can summarise the points: - a tuned counterpoise (when correctly tuned) could be thought of as being opposite in
Hi all, I have had good results with nylon "fishing line", otherwise known as monofilament nylon line. Down this way the thicker stuff is sold as "marlin line" and it seems to last for a few years be
Hi all, The ground path (actually multiple paths) between "dipole" ends is lossy compared to copper wire, so the circulating current is generally lower than if ground wires were used, however the ape
G3XDV, the about a S-point stronger, but that could be be it signals the showed an Very interested in this report from Rik. At the time I announced my success, Rik spent some time running through the
Hello LowFers. I have made loop ant for rx and it seems not to work satisfactorily. Size is 1.75m x 1.75m. Everything is done as usual, with grounded middle and amplifier with 2 x BF245, tuned proper
Dear LF Group, Many thanks to all those who responded to my request for information regarding automatic ATUs - I now have several leads to go on for my research. Cheers, Jim Moritz 73 de M0BMU James,
Hello (V)LF experimenters, I have an idea of resonating my existing vertical on 8 kHz. Is there a practical way to construct a 600 mH loading coil, withstanding 3-4 A and high voltage? Any *large* to
Besides just noting the change It would have been interesting, of course, to find out into what direction the ground resistance has changed. On one of the last cold days and before the snow had disa
James Moritz wrote: snip snip Since soundcards and software like Spectrogram have many other uses to radio amateurs apart from reading QRSS, it would be interesting to know if any data exists about t
