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Topband: Loud clicks

To: <topband@contesting.com>
Subject: Topband: Loud clicks
From: "Larry" <lrpmbt@comcast.net>
Date: Thu, 31 Dec 2009 12:52:28 -0500
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Lately I have noticed loud clicks on the on the first dit of a transmission on 
a few stations. We just went through that same problem with W8UVZ and 
discovered that his TR relay was going bad on the amp. After replacing the TR 
relay we discovered the rig was keying too fast for the amp (xmt delay) thus 
hot keying the amp. It also caused the first dit to be distorted or missing 
altogether. Some of the older amps have slower open frame relays. BTW we found 
exact replacement relays at Digikey. The clicks remained even after replacing 
the relay.


Here is what we discovered after replacing the amp TR relay. The amp TR relay 
operates at 20ms, the Yeasu FT1000d operates at 12ms and the K3 default is 8ms. 
The K3 was reprogrammed to 16ms and the problem went away, However the FT 1000d 
xmt delay cannot be changed. I found a simple circuit to speed up the TR relay 
on the amp (see www.k6xx.com ) fast relay for details. This circuit brings the 
amp operating speed to approx 10ms without damaging the relay. If you have a K3 
just go into the xmt setup menu and change the xmt delay to 16ms. This should 
prevent any damage to your amp relay and or tubes. The Yaesu Ft1000mp has a 
programmable xmt delay in the CW break in setting. Menu 7-4

                  73 es HNY Larry W8VVG
_______________________________________________
"160-meters is a band for men, not for sissies!" - SM5EDX

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