The ferrite rod is tuned with a parallel capacitance of around 1400pF. The antenna is connected to the top of the tuned circuit and the antenna current meter is in series with the antenna. A 50 ohm t
0.18A and an assumed Heffective of 3m Andy. 73s Roger G3XBM On 11 January 2011 18:39, Andy Talbot <[email protected]> wrote: What antenna current are you getting? - OR - What is the total resonan
What antenna current are you getting? - OR - What is the total resonant input resistance of the vertical + ground system (before any matching network) .and the RF power being delivered into this,
5w 73s Roger Sent from my iPod Touch 4g On 11 Jan 2011, at 21:17, Rik Strobbe <[email protected]> wrote: Roger, what power do you need to get 0.18A into the antenna ? 73, Rik Van: owner-rsg
If I understand corrrctly, you're measuring the current into the tap then? In any case, I doubt a ferrite rod even at that power could be linear as a loading coil For example :: Using the approxima
Roger, Maybe there was a kind of "utilities assisted earth mode" on the loop at 3 km distance, as you call it? How high is the antenna and where is is placed? I hope its on the roof of the house :-)
From now until late this evening I will run the WSPR beacon (136kHz USB dial) in the hope that a few more people will be able to copy the QRPp signal. Please have a go and let me have any reports. 73
Yes Rik, the ferrite rod ATU is just sitting on the bedroom table. I used a similar arrangement quite successfully on 500kHz but this, plus the very short vertical, are not good enough on 136kHz. At
Roger, Maybe there was a kind of "utilities assisted earth mode" on the loop at 3 km distance, as you call it? How high is the antenna and where is is placed? I hope its on the roof of the house :-
Hello Roger, 3m Heff @ 2200m --> Rrad = 1580*(3/2200)^2 = +/- 0.003 Ohm radiated power = 0.18^2*0.003 = +/- 100uW Gain of a short vertical = 1.83 --> ERP = +/- 180uW But "greenery loss" can be up to
Hello Roger, "coil on the bedroom table" : do you have the loading coil indoors ? It might be worth trying to place the coil outside to reduce losses. 73, Rik ON7YD Van: owner-rsgb_lf_group@blackshee
Hello Roger, 3m Heff @ 2200m --> Rrad = 1580*(3/2200)^2 = +/- 0.003 Ohm radiated power = 0.18^2*0.003 = +/- 100uW Gain of a short vertical = 1.83 --> ERP = +/- 180uW But "greenery loss" can be up
Odd. At 3km G6ALB 'ought' to be in the true far field. but I do wonder if there could be some ground current "ducting" - eg if you have any underground power-cable runs in common. You' be on sepa
