Hi Stefan
Nice set up at ur station.
A couple of points ---
Your coil with a Q of 1000 seems very high and how high can a Q get ?
Your antenna is just a horizontal wire 70 metres long hanging between two
buildings 30 metres high. You have a vy good signal for this simple
antenna.
I can see you resonate your 3mH coild with a motor driven variometer but how
do you match this to exactly 50 ohmz for a SWR of 1:1 to the TX
I can see your coil and transformer secondary are in series to earth but no
adjustment for matching.
Maybe I have missed something
73 gl de mal/g3kev
----- Original Message -----
From: "Stefan Schäfer" <[email protected]>
To: <[email protected]>
Cc: "Roman" <[email protected]>
Sent: Saturday, December 17, 2011 4:23 PM
Subject: LF: TX system at DK7FC, schematic
> Hi Terry, LF,
>
> I want to add something to the TX/antenna matching discussion. There
> have often been querys about a schematic of my TX/PA system. So i
> finally took the time to draw it, how it looks in principle. It is just
> one example how it can be done of course. Maybe it helps to get further
> ideas how you can do it one your side.
>
>
http://dl.dropbox.com/u/19882028/LF/DK7FC_137kHz_TX_antenna_and_PA_schematic
.jpg
>
> Best 73, Stefan/DK7FC
>
>
> Am 17.12.2011 15:00, schrieb Terry GW0EZY:
> > First of all thanks to Andy for starting the Wellbrook discussion - it
has
> > been very useful for me.
> >
> > James - thanks for the information on the pros/cons of using Litz wire.
> > Although it seems obvious now, I hadn't realised the meaning of 10/44.
> >
> > Mal - thanks for your helpful advice and info on your antenna loading
> > arrangements. I am still trying to picture it all in my mind but it
seems
> > like the sort of relatively simple system I'm looking for - especially
> > keeping to 50 ohms. I have yet to find a supplier of the metal lined CH
pipe
> > (Srewfix B&Q??)
> >
> > [...]
> >
>
|
