I was out with my Tracker and mobile igate today. I missed some messages for Roger MW0IDX (but they arrived). I was also testing a mobile antenna. I tested it on a route that I drive regularly. The new simple 1/4 wave antenna on a mag mount outperformed my usual, much longer, dual-band “gain” antenna. Not really surprising.
I have mentioned before that many of the dual band antennas work poorly on 70cm. They may give a reasonable SWR, but any “gain” and radiation is not focussed towards the horizon.
My hil based digipeater project is moving along. Digipeater (for siting atop a hill) and igate (to capture digipeated packets and route onto internet) now constructed and under test.
Hoping to get the combination fully live, using a relatively easy to access hill, later in the week.
Dave has done a great job with these - they are really great. I’m building mine up here, initially to test in digipeater mode on various hill locations for Raynet activities locally.
Ah the well known expression “The difference between theory and practice in practice is different to the difference between theory and practice in theory” is working!
Reflections, diffractions and things above the local horizon being the main effects.
EDIT: It would be interesting to see the effects of ground reflections and the constructive and destructive interference on such a low mounted an antenna. Does the frequency alter the amount of reflection/absorption of ground?
I can’t help thinking that a few feet off the ground would make a significant difference in performance but it’s better than nothing! Thanks to M0MZB for installing it.
A few wavelengths would help. I’ve seen the effect of leaving a 2m handy stood on the ground on activations not hearing any other activators. Pick it up and stand up and there are people talking!
It’s good that there’s traction with this and there are more units being deployed. Noticeably quiet up here… but my club will be looking at installing something with a few remote sites for consideration.
Am following with interest as the nearby hill would give good take off to G/TW and some G/NP hills. Just need a chat to the gamekeeper and to start building ……
My priority is to keep it inconspicuous…the ground falls away quite steeply adjacent to the location. However, it’s fairly open moorland so I don’t want to put the antenna on a pole.
I wrote my phone number, along with some other stuff that makes it seem like some sort of “environmental monitor”, on the outside of my guerrilla igate. I then cable-tie it (with very thick ties) to existing fence posts and similar. It has been in full view in a number of locations without problems. It will be deployed again next week.
I also tend to deploy it in places where the likely ownership is ambiguous - and not being concealed will hopefully lead people to think it should be there.
