Topband
[Top] [All Lists]

Re: Topband: INVERTED_L_ANTENNA_MATCHING

To: goofyham@highstream.net, topband@contesting.com
Subject: Re: Topband: INVERTED_L_ANTENNA_MATCHING
From: Telegrapher9@aol.com
Date: Sun, 3 Dec 2006 19:35:04 EST
List-post: <mailto:topband@contesting.com>
George,

I tried an L-network and it will match your antenna on 80 and 160 meters. The 
L is configured as a series inductor at the source end and a shunt capacitor 
at the load end. 

Values to match your antenna:
80 meters: 20 uH and 30 pF
160 meters: 34 uH and 580 pF

The antenna input Z:
80 meters: 92 -j600 ohms
160 meters: 20 +j240 ohms


Component stresses at 1500 watts:

80 meters:
capacitor: 3.4 kV peak, 2.3 amps RMS
inductor: 5.5 amps RMS

160 meters
capacitor: 3kV peak, 14 amps RMS
inductor: 5 amps RMS

So it looks like a rotary inductor good for 5 amps will do it along with a 
capacitor good for 5 kV and 15 amps.

An alternative is to build two fixed component matching networks and switch 
them in with relays. Or, it might be possible to build a non-switched 
compromise network and finish the matching with a tuner at the shack. If you 
are 
interested in any of these I can look into it. 

   Dave WX7G
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband

<Prev in Thread] Current Thread [Next in Thread>