i saw an article in a back issue of a ham magazine, telling how to make one of these. well, my yaesu '817 is kind of an ht, and since the rubber antennas i have don't work well i thought i'd make a mousie tail. the article called for 19.3" of wire attached to the bnc mount by a large ring terminal. i didn't have one that size so i got the 'brilliant' idea of using a small ring terminal and attaching the wire to the grounding screw on the back of the radio. total...flop. i tried shortening/ lengthening the wire to no avail. no improvement. i had put the antennas on my antenna analyser to get the swr spread, and then did the length adjustments. later today i'll attach the mousie and antennas to my analyzer and see what happens. it has a grounding lug. feedback?
Well, what you are referring to is a 'counterpoise"/radial. The specific dimension is 1/4 wavelength at 2m. So, it is no surprise that it has no effect for use at HF. It works just fine with my HT's. I always carry one in my pocket when afield. Cut your counterpoise/radial to the appropriate 1/4 wavelength for the band(s) you want to operate and you should have better luck. Let's review the math. Formulas approximating length including End Effect. Memorize them and you will always be able to quickly throw together a resonant antenna anytime! 1/2 wavelength = 468/Mhz = Feet 1/4 wavelength = 234/Mhz = Feet (note this is 468/2!). p.s. The foregoing assumes you are using an unbalanced whip (vertical) antenna at the back of your radio. If you are using a balanced antenna like a dipole (or a vertical at a distance fed with coax), then the counterpoise/radial will have little effect since it is carrying little or no current.
wow! that was a quick response!! i thank you! i guess i wasn't clear as to frequencies. the tail IS for 2m. the 19.3" is ~1/4 wavelength for 2m, my head hurts. will go fuss with it some more.
Well, the radio is already of substantial size, especially compared to the average miniature HT's used today. So, the radio chassis may already provide a substantial RF counterpoise, such that adding a wire is not significant.
I find a proper cut counterpoise allows the use of the mini whips for hf on the 817... Without them, nearly useless. 2m, never thought to try...
Why do they use the silly term "mousie tail" and not just call it a counterpoise? nothing mean meant to the OP - but in a technical hobby, why not use the technical term? I don't get that Dave W7UUU
Yep. Another silly name for the proper term: "counterpoise" Why not use the proper name? I just don't get that... these are opportunities to teach new hams about concepts and terms. Not a time to teach silly little kid words like "Mousie Tail" etc. Dave W7UUU
The BIG Motorola HT200 (introduced in the early 1960's) had big back covers made of ... must have been aluminum. The HT200 was a little slimmer than a brick, but had about the same outline. A good grip on the radio with the right hand grasping the back radio placed the bulk of one's hand in good capacitive-coupling position on that back metallic cover ... and little wonder, if weak into a repeater, pointing one's elbow down while facing the repeater (and holding the radio just a little higher than normnal) resulted in a stronger signal into said 'machine'.
