hi - Miniwhip - not that this is an exacting science I have a length of six inches as an optimum in urban location with no large MW stations nearby -well more than 50 miles away - I used DCF39 as a marker and MDS on Argo dot 60 with differing lengths of "whip/board" whilst in Shanghai, but the difference from the designed couple of inches to 6 inches was just, just discernible maybe less than 1dB. As people say just taping/coupling in the capacitance and above a certain value it shouldnt make any odds.
On some of my eprobes and I have three or four at times in operation here, I have a BNC on top of my baby bottle so can add and subtract lengths - improvements do exist when using it on HF/500Khz with a longer length here in singapore, but geography, local signals and oddles of other variables makes this kind of plug and see. The improvements are probably because the components are designed for VLF/LF and get kinda reactive as you go HF and I would perhaps optimize the coupling caps/power iso values if I was going for a dedicated HF unit. As it is,the probe works within a 2dB ( or less) of a quarter wave vertical at 10Mhz, and certainly less of a target/static or otherswise.
I couldnt have a "longer length" probe in my new home in Alaska due to the plethera of v/m station on 530KHz area making a mess - I already know its not going to be my solution there when I finally put down, but here its fine.
Ill be looking stateside again tonight on 137 and 500 for Eu at your dusk. Thats if these @#$#@ storms will stop. Sun is shining for the moment...
Interestingly enough and tempting fate Im still on my first FETS on all the probes but I really do bond everything pretty well so maybe thats been the saving grace.
Laurence 9V1 LF
From: [email protected]
Date: Tue, 6 Nov 2007 20:32:28 -0500
To: [email protected]
Subject: Re: LF: WD2XGJ with miniwhip antenna
Next one is planned for a half inch diameter plastic tube........
and going down:-)
Should have mentioned that the aim, as always, is to keep the length to no more than 5 or 6 centimetres.....
and that's aside from any perverse observations:-)
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