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[WriteLog] ptt line resistance?

To: <writelog@contesting.com>
Subject: [WriteLog] ptt line resistance?
From: sjwoodr@yahoo.com (Steve Woodruff)
Date: Fri, 8 Nov 2002 20:04:56 -0800 (PST)
Joe,

THANK YOU!  You were right.  I dumped the
diodes and extra resistor, and changed the
RTS resistor to a 1k ohm and its keying
bueatifully.  Exactly the type of help I
was looking for... and an explanation to
go along with it so i understand why i
changed things.

Thanks!!!

Steve, N9OH

--- "Joe Subich, K4IK" wrote:
> 
> 
> > 
> > my ptt circuit uses RTS from the cw serial
> > port, goes through a 4k7 resistors, then 
> > in parallel with a diode and another 4k7
> > before hitting a 2n2222.... and then a
> > final diode before having a PTT + and a
> > ground line. 
> 
> Eliminate the diodes and change to a single 1 K
> resistor. 
> You're not providing enough base current for the
> 2N2222 
> to fully saturate and the diode in series with the 
> output of the 2N2222 causes an additional .7 volt
> drop.  
> 
> 73, 
> 
>    ... Joe, K4IK 
>  
> 


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