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Re: Preamp

Quoting Paul Luggar <luggsey@hotmail.com>:

> I suggested a preamp on a handheld would possibly overload the front end
> of 
> the radio as my Kenwood THD7E overloads with the arrow when I go
> hilltopping 
> with it.  With a preamp and local conditions in the UK it would be
> useless, 
> "If" RF conditions are super quiet then it may be ok but why preamp with
> such a short feeder?

While it's often stated that a mast-mounted preamp helps to overcome the
losses in feedline, the low-noise preamp's advantages go beyond that. In
this case, if the preamp has a lower noise figure than that of the first
stage of the HT, a more sensitive overall receiving system will result. 
This increased sensitivity comes at the loss of some dynamic range,
however. On the whole, in low signal work, we need to aggressively reduce
local noise anyway to hear the signal, with or without preamp, so the
trade-off is a good one for us.

73, VE9QRP
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