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Subject: [CQ-Contest] QRP
From: W8JI@contesting.com (Tom Rauch)
Date: Sun Mar 31 06:45:55 2002
> Who says that the filters and shift as we in the U.S. see it (700-800
> Hz) is standard in other parts of the world?  Could it be different
> elsewhere, especially among foreign domestic radios? Could it be a
> design thing since there may still be many homebrew transceivers over
> there...?

it doesn't matter at all, not one tiny bit, if we like to use different 
receive tones.

As long as the transmitter is properly netted to the receiver in 
EACH station, they will be on the same frequency when transceive 
no matter what pitch each station operator uses.

The only problem is some radios don't net the transmitter to the 
receiver, or the user changes pitch by fiddling with passband tuning 
without getting inside the radio to change the carrier oscillator 
offset to match. 

The FT1000 has a set of switches for offset, so when you set the 
switches to 500Hz (or whatever) for your favorite tone the 
transmitter comes out right spot on.

My old 751A's have an internal adjustment.

Ten Tec radios are particularly bad about this, because if you buy a 
"low pitch" CW filter the transmitter offset remains fixed for the 
higher frequency CW tone design.

       
73, Tom W8JI
W8JI@contesting.com 

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