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Hi MF
Interesting conditions to Reunion last night
A total of 23 spots from FR5ZX. Only four stations reported
1 from G8HUH at -30
3 from SV8CS best -24
6 from DK7FC best -24
13 from EA5DOM best -19
From Rick Strobbe ON7YD reference site for LF antennas I have seen his calculations for a vertical
antenna with inductive topload. May be is the closer configuration to what I have managed to get here
There is no mention to the feeding point for such antenna. In my setup H(L) is 80m and I'm feeding
at the coil base. Total H is 80+11= 91m
The Ra calculated from Rick formulas is over 8 Ohm (not mOhm)
This radiation resistance seems too much to be true. But results are proving really outstanding
I'm just feeding the antenna with 70W, believe it or not and it is not really resonanting on WPSR frequency but on 488KHz
as I adjust the variometer up at the antenna and then run a coax line to shack which changes it all
The 80m pipe which forms the H(L) is really more complex in practice. It goes down to building basement
and there splits into different pipes. One connects to presure compressor and water tank. The other runs
underground 40m to the twin tower and then runs up again another 80m into the twin (parallel) tower
The pipe section running underground is not metal, but plastic. The iner water column should work as
current conductor. That water is confined in the pipes and presurized. Should be saturated with metal oxide
similar to a heating circuit, so probably the plastic pipe got metal deposits inside which make it even better
conductor than the water colum itself
Any thoughts ?? Am I getting >10% efficiency ??
From WSPR database, FR5ZX transmitted in 503KHz. Is 630m band not allowed in Reunión?
73 de Luis
EA5DOM
Enviado en portable
------ Mensaje original ------
Desde: DK7FC
Fecha: 09/11/2015 14:48
Para: [email protected];
Asunto:Re: LF: Re: FR5ZX on MF WSPR
Hi Genosse Roman,
FR5ZX is using a resonated vertical antenna with capacitive top load near his house. He also transmits with this antenna.
73, Stefan
Am 09.11.2015 01:35, schrieb Roman RW3ADB:
Parteigenosse Stefan!
Any news about FR5ZX RX-setup? )
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