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Date: Sat, 28 Jan 2012 16:55:32 +0100
From: =?ISO-8859-15?Q?Stefan_Sch=E4fer?= <Stefan.Schaefer@iup.uni-heidelberg.de>
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Subject: Re: LF: Conds
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Hi Rob,

Am 27.01.2012 21:28, schrieb Rob, M0DTS:
> Ok I'l TX shortly on .710 QRSS 60 full call.

Better try between 136.168...136.176 kHz. There, all the spectrograms 
are running in QRSS-60 mode. You will see it at G4WGT and maybe others 
like F1AFJ, DF6NM, DK7FC, OE3GHB...

>
> Antenna is up with three fibreglass poles so at full height for now, 
> might try to get centre/vertical up to 12m.
> All the local trees are 50+ meters away but i have 2m high buildings 
> around the yard..
That sounds not to bad. So i expect your losses can be improved by 
reducing the ground and coil losses. What is the C and/or L and the Q it 
this coil? Make sure the coil is not coupling to nearby lossy objects. 
Ideally there is nothing like air in a distance of the length of the coil.

>
> No mains at the base of the antenna so unfortunately that is no use, 
> currently a single 1m/50mm rod into the ground.. yes just one!
Ah, that sounds good since it sounds like you can easily improve the 
situation. I would suggest to use 10 of them, located below the wire. 
And you can connect the mains earth in parallel by using a cable to the 
house.
Build a RF amperemeter and check for the partial antenna currents and 
the overall current of course.

As Alan suggests, increase the top load if possible, to reduce the 
voltages. Then you can increase the TX power :-)

Good luck and hope to see you soon! :-)

73, Stefan/DK7FC



>
> Rob
> M0DTS
>
>