Further to my previous messages on this subject.. It will be a while before I know whether the calculated value for wire shortening due to insulation is correct. Some low-life has broken into the hut
Many thanks to all for the replies received. I finally did what I should have done in the first place and went to the fount of antenna knowledge - W4RNL. On his web page there is an article which cal
I have some beverage antennas for 160m reception which are fed through a long (>2000') length of 1/2" 75 Ohm hardline. This is the older type with a solid copper inner conductor - I believe that more
I tried to send this directly to Bill, but got bounced, so please excuse the bandwidth here. The real answer is between about 1% and 7% depending on all sorts of things. That can really make quite a
or just to keep to the same system of measurement, something close to 2370kg! Roger VE3ZI ___________________________________________________________ALL-NEW Yahoo! Messenger - sooooo many all-new wa
I have separate 7MHz and 10.1MHz quarter wave vertical antennas which are spaced about 60' Both have about 60 radials and the radial fields do therefore cross each other to some extent. There is a ve
I was idly thinking about copper clad steel wire as used for antennas today. I have seen it written several times that if the copper coating is thin, it is ok at high frequencies, but not at lower on
I am constructing a vertical array, where the driven element is a base fed half wave vertical. Because it is close to resonance and closely coupled to the parasitic elements the drive impedance chang
An anecdote: Yesterday several of us were working at my (borrowed) commercial tower putting up my new 160m antenna. The tower owner has a VHF 10C4 at the very top of the tower (325') fed with Heliax.
A little while ago I posted a message about 40m and 30m quarter wave verticals which were fairly close together and fed over the same feedline. The 30m one worked well but the 40m one was a disaster,
Sorry, but I just have to stick my oar in here! Even cable with a perfectly conducting 100% outer shield will radiate to some extent. This is because the diameter of the INSIDE of the shield is less
Can anybody help me with a definitive method for adjusting a PI Network ATU? The unit that I have is an ex-military motorised/preset tuned one. It has a 50:200 Ohm WB transformer at the input. Input
....In emergencies I've 'borrowed' my wife's dish washing soap.... What sort of household is this? Where I live, it's 'my' dishwashing soap!!! Seasons Greetings to all 73 Roger VE3ZI ________________
Braid coverage percentage does not in itself define the leakage of a braided coax. Leakage (or the more easily measured coupling loss) is a function of nearly all the cable parameters, including the
The temperature here this morning is -38C (-37F).... Just for the heck of it I tried my rotor (Emotator) and it turns fine, although quite slowly. I have taken no special precautions at all against t
Bruce This must have been upsetting to say the least. I presume that you have contacted Titanix, and wonder what response you have received? Without question the manufacturer should be the one to sol
I have not tried a vertical dipole on 40m, but can report somewhat similar results with a 40m quarter wave vertical versus a horizontal dipole at about 40'. The vertical was in the clear and had abou
I have three of the ex UK military Clark 'Scam' 40' pneumatically operated towers. Whilst I agree with the caveats from Ian, GM3SEK, I have actually found them pretty good for fixed operation even he
My experience (admittedly really limited to 160m) is that it is pretty easy to get ~50% efficiency. It is pretty hard to get close to 100%. My justification for saying this is that at one point I had
G3XJP published his 'Pic-a-Switch' a few years ago in Radcom. This sensed the rf frequency and used relay(s) to select the operating band(s). Unfortunately I have mislaid the copy in which it was pub