Recent content by PhilipB

Hello again, I got so fed up trying to homebrew a GM and not getting it right (or anywhere near) that I have just purchased one, it is up on the short test pole in the garden at the moment but even down low it is working quite well, swr plots are spot on and it even performs reasonably on 15m...

Hi Gamegetter, on my quest to find out if it is possible to homebrew a cheaper low power version of the GM I have been directed to this similar antenna build link, it is a very interesting read and has answered some of my questions regarding the bandwith and the capacitor. Hope you enjoy it...

GM antennas Hey Marconi Ive been looking at all your GM Vs other antenna vids nice camera work, I am not going to comment which one I like the best but out of curiosity how many antennas do you own? Ive heard of antenna farms but you must be growing a greenhouse full of antenna seedlings:ohmy...

Very interesting thank you. Finaly got through reading this full thread, very interesting Marconi! I used to have a similar antenna to the sigma 4 it was called a Comtell 444 and it was 31ft tall! the neighbours were so scared of it comming down in the wind they used to walk on the other side...

Hi Folks, looking to put an old Major M588 that has been given to me back into service on the CB bands, this thing has had the clarifier unlocked, PLL02A frequency jump mod, 10kc jump mod and all onto the now unusable stock switches and its a pain, I constantly get lost on the darn thing with...

HB GM One thing I forgot to mention is that this is first antenna I have ever used that tunes up exactly as it reads in my MFJ antenna tuner manual as per the settings recomended and tunes very easily! so even though it is a pityfull effort it does have something going for it. Phil

Thanks Shockwave. Phil 26WF183 M6MRP

HB GM I knew I had seen something similar to this before, here is a similar Home Brew coax stub matched antenna for 5/8wl on 20m (dont understand any of this either lol) Matching a 5/8» vertical - example 1 Phil

coax capacitance Dont ask me the whole thing has me bamboozled:blink: I read a thread on a physics forum about coax capacitance and it seems there are many variables to consider and the makers of coax only quote the capacitance for the coax at very low frequency levels so by the time you get...

Hi Marconi, just tried a coax choke/Ugly balun coil with thiner coax on a 6cm (slighly less than on the plans) former and it comes close to your coil legnth and the 331.5cm coax run given on the plans so it is mm that are the diamensions given, rain has stopped play here "again" going to try the...

Hey Whiplash, just had a look at a 2012 out of curiosity and it looks like an enclosed RF tuning coil at the base not an ugly balun as they are called? others on here may have better idea, but if you have problems with tvi I would give it go it worked well for me with only 5 coax turns on a 9cm...

Last two pics tried to photograph the full 8m in situ but cant get far enough away in this small back garden Phil

Variable plate cap try and coax caps tried few more pics, quite easy this way thanks for the advice, what is the basic fundemental desciption of this antenna design? as it is not just a vertical .64 wave, I have seen similar types for VHF with stub matching and coax caps and I think they were...

balun and pole in situ As you can see Im not a very good photographer, lets try this paper clip thing.

Ugly Balun Sorry whiplash I cant help at all with that one:blink: but I did have to put one on the bottom of my comtell 444 (same as sigma4) when I had it due to massive tvi problems and it worked well, no more tvi, lower swr and a slightly better bandwith? dont know how it worked but it...