I wonder how bad the varicouplers really are. The they often don't have a
rolling or rubbing contact like roller inductors because a piece of very
flexible wire can be used. Also, you can go from max. inductance to minimum
80 degrees. At minimum their Q's would be low but L-networks have lower
Q's than T-networks. The Q goes as the square root of impedance ratio. So
if you matching 50 ohms to 5000 the Q would still only be 10.
73
Bill wa4lav
At 05:37 PM 11/17/2006 +0100, Peter Chadwick wrote:
>Peter said:
> >My first TRX in 1963 was a Wireless Set No.19 MkIII equipped with the 807 in
>the final.
>That radio also used a variometer as an ATU, it was a very quick and
>reliable means of coupling random wires or verticals to the rig from 2-8MHz<
>
>
>I had forgotten the 19 set - mainly, I suppose, because I never had a very
>high opinion of its performance!!! But yes, it had a variometer in series
>with the antenna.
>Other than in the 500kHz region, I never saw one used in a tx over 100
>watts or so, although that doesn't mean a lot. There may well have been
>QRO tx's at HF that did.
>73
>Peter G3RZP
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