Re: AGC and…CW Decode

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Re: AGC and…CW Decode

Jim Rogers, W4ATK
         I admit it. I love my CW but am "CW Challenged".  I was taught Morse code by the U.S.Navy in Radioman School and had to master 20 WPM to graduate. How I struggled. Finally after being set back two weeks I finally got 20 WPM and was able to go on to CT school for the balance of my training. I went straight down to the FCC office and got my general class ticket.
       
        Thankfully, the Navy decided to make me a non-morse operator in CT school and I spent the balance of my naval career as a CT "O branch" operator. I have been operating mostly CW since getting back on the air in 2004. I can copy call signs well at much higher speeds, but am most comfortable around 18 WPM for rag chews.

        I find that the CW Decode feature of the K3 to be a great assist to someone of my questionable talents. Most decoders suffer from an susceptibility to noise, so anything you can do to improve the signal to noise ratio is beneficial. The decoder in the K3 is one of the best I have ever used. When a "K3 rookie" friend asked for help in using CW Decode, I came up with a procedure I use for copy those weak DX signals.

        One note of caution, turning off the AGC without decreasing the RF gain before doing so, can result in a loud CRASH from your headphones or speakers. I also have the AF LIM set to protect my K3 AF amp.
CW Text Decode on the K3 W4ATK style.
1) Set MODE to CW.    - makes sense.
2) Set AF Gain and RF Gain fully CCW (counter clockwise, all the way to zero).
3) HOLD AGC (turns the AGC off)  
4) If a special VFO B display mode is in effect CANCEL it.
5) HOLD TEXT DEC, the select CW 5-40(or 30 - 90)  using VFO B. (You will see a small "T"  below the CW icon on the display).
6) Adjust the threshold (THR) using VFO A,  AUTO or 1 to 6.  ( Around 3 to 4 works for me most of the time)
7) Tap CWT to exit.
8) Advance the RF GAIN to 50% or so.  Advance the AF GAIN to a comfortable listening level
9) TUNE in a CW signal and adjust the RF GAIN for best copy.
10) After the signal is tuned in and copying, try reducing the WIDTH to 100Hz (0.1).
Using this procedure I can copy some very weak CW signals, weak enough to not be easily discerned on the P3.  As I move about the band looking for contact I widen the selectivity as needed and ride the RF gain.
Jim, W4ATK
Licensed 1953
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