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Fw: [Towertalk] Newbie Question

To: <towertalk@contesting.com>
Subject: Fw: [Towertalk] Newbie Question
From: W8JI@contesting.com (Tom Rauch)
Date: Thu, 18 Jul 2002 18:58:21 -0400
> That 3 db (or so) comes to about 1/2 of a "S" unit- still not usually
> enough to make, or break you.  and even it can be mitigated by preamp
> on the tower , in the recieve direction.  signal would have to be
> pretty far in noise (close to  10dB above mental tepathy  :>) ) for
> this loss to kill much . as info, jim nn7k

3dB of transmitting power increase can sound like a major improvement 
to the other guy when signals are close to noise floor.

As a general rule feedline loss, like antenna gain, is unimportant 
for receiving. Generally the directivity of the antenna dictates the 
S/N. The consistent advantage appears only on transmit.

It also helps to keep in mind the 6dB per S unit is mostly a dream. 
Most S meters down low on the scale are about 1 dB or so per S unit. 
They generally approach 4-6dB per S unit near S-9. Many receivers 
were intentionally designed (Drake/Collins, etc) to be 5dB or less 
per S unit.

The bottom line is for ragchewing no one would notice 3dB a very high 
percentage of time. For competitive use, like DX'ing in pileups, 3dB 
could be worth the extra investment. Just don't plan on 3dB less loss 
helping the receiver at HF, unless you have a dog of a receiver.

73, Tom W8JI
W8JI@contesting.com 


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