Chapter 4 contains discussion of antennas, both in air-cored and ferrite-based. Although it principally deals with subterranean situations you may find it useful. John F5VLF G3PAI Amongst some ferrit
Somewhere I have a paper describing something like that. I recall an antenna at ground level or actually a little buried, and its effective height was related to the depth of the water table below th
This one is quite handy but not suitable for several kV. They do seem to be expensive but I have 3. Hugh M0DSZ Hi Andy and Genossen LFers! The hi-voltage relays problem will be solved by serially
Can you "mute" the receiver, i.e. kill the internal power during TX, possibly just to your LT5524 stage, short circuit the input before it reaches anything active or kill the power to your active ant
I assume that as this is high impedance and tiny current into the amplifier that ferrite beads may not be quite so so effective. I do like them though, cheap and easy, removable with no damage. If yo
If anyone noting my signal reports, WSPR in particular, is puzzled by large variations, this is because I am switching between aerials. Best results are on the main Tx aerial into my R5000 but, faili
I can't really "do" MF at present but I know that when my LF WSPR transmissions were "lop-sided", that is the I and Q channels in SSB mode were rather different, only one station was able to decode m
I bought a 300W amplifier kit, all the small transistors have an "ft" in the VHF region and the power transistors ft is 15MHz. Small modifications include changing the Zobel network and bypassing som
It comes from HongKong via Ebay usually as a kit but also ready-built for only a little extra cost. If you look for a business called "HiFiSpot" it gives you a number of interesting thingsnow includi
I received R7NT for the first time late yesterday afternoon, using Opera, just over 3000km, at -42dB. I'm not sure if any of my reports are uploaded anywhere. Hugh, M0DSZ Good signals from R7NT on 13
Glancing back at the WSPR reception report list at 1434 today I noted one from OL9TIT on 137.404 kHz at -32dB s/n. Thinking this was some sort of Titanic beacon from the Czech Republic and that was a
Thanks Andy, I've saved the PDF file, I don't use Yahoo so don't see all postings and certainly didn't spot the 0 rather than O on a 12" monitor. On 30/12/2015 21:18, Andy Talbot wrote: This is a wel
Looking at the "org" website it's passable in the mornings here but if you stay logged on it drops you eventually so I suppose decode reporting suffers much the same fate, congestion on the server(s)
There a few "audio" transistors about, I am using Toshiba complementary pairs 2SA1947 and 2SC5200 (4 of each) with 320W dc input. Naturally there is plenty of heat to dissipate so I fitted large heat
Briefly, just on WSPR: LA3EQ from 1410 to 2058 on 137.530, -28dB to -33dB On Opera: R7NT at h:32 on 137.541.2, -26dB to -35dB plus some "deep search" reports UT7GH at 2049 on 137.510.2, -27dB RN3AGC
Opera results Feb 13-14th from 2303- R7NT -36 to -41dB from 1043- LA3EQ -29 to -35dB from 1955- SO5AS -33 to -42dB 1220 IY8OYF -31dB 0022 G3XDV +1dB WSPR results Feb 13-14th from 0954- LA3EQ -24 to -
Apart from requiring a higher power supply voltage I find a complementary pair (or pairs) of transistors to be satisfactory and, although the NPN and PNP sets should be reasonably matched to each oth
My Reports March 5th to 6th (assuming there's any interest) (The internet link seems to disappear occasionally) Opera: LA3EQ -29 to -31db 1315 to 1647 Sat LA3EQ -32 to -35dB 0707 to 07
My Reports March 5th to 6th (assuming there's any interest) (The internet link seems to disappear occasionally) Opera: LA3EQ -29 to -31db 1315 to 1647 Sat LA3EQ -32 to -35dB 0707 to 07
