The first time since some weeks I had the time to spend some hours in the shack last weekend. Due to late-night activities (barbeques) I missed the early morning and so the low-QRN period. But even d
There are two factors to be considered, sensitivity and selectivity. A dc-receiver can be made as sensitive as a superhet. ... I think that a third factor has te be considered, especially on LF : the
Is this really vaild? Ground reflection surely must depend upon: (1) The efficiency of the local ground connection and (2) The conductivity of the ground both of which must have a much greater effec
One more thing to mention : when you MEASURE your by the way Dick suggests you don't have to take in account any multiplication factor if you have a short vertical antenna. When you measure at 2 .. 3
At 09:21 17/07/99 +1200, ZL2CA wrote: Hi all, One New Zealand amateur, Bruce ZL1WB, uses a very long wire strung out over a gully, and with only 30 watts of RF power applied, is the most often copied
Driven as dipole over "average" ground it will be a nice cloudburner with -10 dBi. At 5° elevation you will get -31 / -16 dBi ("8-pattern"). Feed point impedance will be approx. 5.5-j500 Ohms. Anyon
At 23:11 19/07/99 +0100, you wrote: Well Rik, if nothing else it would be fascinating to hear how well it acts as a receive wire. I presume it will be the usual steel cored wire so it may not be too
At 00:09 21/07/99 +0100, you wrote: Mike G3XDV, mentioned using DCF39 as a standard signal for comparing aerial performance, in a previous exchange which culminated in the fascinating article and res
Last night (21-07) DL3FDO I heard DL3FDO calling CQ with a good 559 signal, but he didn't seem to hear my response. Also DJ5BV heard him (549) but also couldn't raise his attention. With G3BDQ he was
I encountered a similar problem when starting on 136kHz (april 1998). Maybe my 'story' will be of some help to others. Whith my first antenna (a 10m high 'umbrella-antenna') and 6 radials each 20 to
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
At 11:50 25/07/99 +0100, you wrote: BEACON ON 136.150 KHZ I have put on air an LF beacon, running H24, on 136.150 khz. This is of a temporary nature and the frequency can be shifted to accomodate tho
I tried to copy the EI0CF beacon last nigt and this morning but no copy. Have to add that QRN was vey bad last night and also QRM level at the lower end of the band is about 10dB higher than above 13
I suspect that the noise on 136 kHz at my QTH is above avarage. I think it must be lower at quite a few stations I have worked. At my QTH noise is rather low, with the 'big' TX-antenna that is locate
Noting heard / seen from EI0CF on 136150 last night and this morning. Rather strange as I heard Finbar many times before with very good signal. 73, Rik ON7YD
I make Finbar's frequency 136.2 rather than 136.15. Would this be the explanation? His signal is 569 with me sending just a callsign at about 5wpm with big gaps. Dave G3YXM I checked 136.1 to 136.3 w
At 18:23 28/07/99 +0100, G3YXM wrote: I would certainly like to try the "meander" aerial mentioned in technical topics in the Rad Com this month. It consists of a quarter wave of wire, grounded at on
Questions: Does anybody know how to calculate/estimate/measure the efficiency of our wire antenna to determine our ERP power? Does anybody know of previous OE activities on 136kHz or is ours the very
Hi all, I dug out a copy of an article by Nathan Sokal (Pres. of Design Automation) that was published in Design Electronics on 20 Sept 1977 titled "Class E can boost efficiency". This turns out to b
