I’ve read that grounding your radio in the field can help transmit a more better signal so I was wondering if anyone does it when they ate activating? If so, how do you prefer to do it?
I am using QRP and mostly symmetric antennas (dipoles). So I do not see a reason to ground the TX.
Even with other antennas like verticals - if the grounding on the TX was to “improve the signal” - I would first consider improving the antenna.
The story might be different with arbitrary long wire antennas. Then your TX becomes part of the antenna. So does the grounding.
My view …
Lars
DL8WJM
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I sometimes run a counterpoise/set of radials from the back of the FT817 when using it directly with the Diamond RHM-8B vertical antenna (so an “RF ground”) but apart from that no. On some summits it would be difficult to belt an earth rod through the stones in any case HI.
Ed.
Good question.
I found when first started using my portable system using end fed wires 1/4w on 40 for vert and 1/2w on 40 again inverted L via a 9:1 Unun was using the CP point off the Unun with a single wire at 1/4w of 40m length. But found it performed better when i took that wire and divided it into four and ran the lengths off at 90’ angles to each other.
Earthing to me is a safety thing we do at home to make sure stray RF’s build up of static to do one and go to ground as station is there a lot longer than a portable station be and a lot of portables are low powered anyways. But if your in a static caravan for more than few hrs like on holiday and yes prob not bad idea to set up an temp earth again for more safety issues more than performance.
My first experience doing Counter poises was in CB bays when you had a DV27 mobile twig in your loft on a metal biscuit tin and you rolled off in four directions lengths of wire or bacon foil to increase the CP of the antenna helped too.
Karl
Normally I do not using a ground system. I’m using either an inverted-V on a PVC-pole, which does not need any ground or a vertical. The vertical is configured as an “Upper and Outer” with one elevated and more or less resonant radial, so an additional groundis not necessary. In case of using and end fed half wave (EFHW) the necessitiy of a ground is severly disputed. I’have tried a Fuchs-Antenna with a special tumer (from QRP-shop) and a ground seemed not to be necessary. But a lot of OMs say the opposite that a short ground should be used. But for me an EFHW is more difficult to hist up than an inv-V so I didn’t go deeper in theory and field testing.
73, Alexander, DL1AIW.
It is important to remember that “ground” does not have any magical properties that make currents want to go to it, or somehow make RF energy disappear. It is simply a mass with some conductivity and an inherent capacitance of around 0.7F.
Mains currents flow to ground because there is a neutral-ground reference somewhere else in the system, e.g. at the supply point or at the substation.
Static discharges to ground simply because there is a potential difference which equalises when the opportunity (a conductive path) arises.
RF currents may flow through ground in the vicinity of a transmitter and antenna because the system is capacitatively coupled to the ground in a complex way. The mass of earth is part of the antenna system, and it may help or hinder it in operating in the manner intended. A direct connection to ground at the transmitter may cause those currents to redistribute themselves in a way that gives a benefit. Or it may not make much difference. In a few cases, a direct connection may reduce currents flowing through the operator, who is also a conductive mass forming part of the network as a whole. The operator might appreciate this.
I usually use balanced antennas with a ferrite choke on the coax at the feed point. The radio Is inevitably coupled to ground typically by sitting on it (and so am I). An attempt at a direct ground connection would change the impedance of that coupling a bit, but it seems very unlikely that that would make any significant difference to the current flow here, which should be very small.
Different antenna systems might benefit from a low impedance ground connection, but it is unlikely to be easy to achieve it.
Some antenna systems might benefit from a DC static discharge path.
Martyn M1MAJ
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Thank you all, I figured the SOTA community could put the issue to test for me.
I meant REST
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