[Elecraft] Re: zero beat detector with KX1?

[Tom Hammond]

>Eric Ward wrote:
>
>>....I have been interested in building some version of a visual zero
>>beat detector that uses a PLL tone-decoder IC for use with the KX1.  I have
>>read about the K2 guys using N0SS's PC board version of the circuit designed
>>by KR5L.  Has anyone tried it (or the Jackson Harbor Press kit, or any such
>>similar) with the KX1?  Is the side tone too fuzzy/harmonically rich to make
>>it work?

Then ... At 10:51 AM 12/1/04, wayne burdick wrote:

>Tom Hammond has put the tone detector in a KX1, I believe. But I think 
>he's off-line for a few days, since he's visiting here in California.

Hi folks:

Just returned home... whew! Great time out on The Left Coast, but ready to 
be back here as well...

Regarding the CW Tuning Indicator installed in a KX1... I think Wayne 
nearly passed out when I told him we'd managed to get the device installed 
and moreover, installed using the MAP LIGHT as the indicator, so that no 
holes had to be drilled... and nothing was hanging out either!!!

Kudos to Pete Ames, NU6Q, who actually performed the installation on his 
KX1 (I no longer have the KX1 I built, it want to Wayne as a 'bench rig'). 
Pete followed my instructions and it appears the install went without 
significant screaming gnashing of teeth!!! We did have a couple false 
starts, but things came together nicely in the end.

First off... for anyone who thinks about installing the CW Tuning Indicator 
into their KX1, drop me a note for my (so far UNpublished) notes on the 
installation AND for some pics from Pete of his completed install.

The connections to the KX1 for DC, GND, and LED are very straightforward. 
However, the AF input to the Tuning Indicator is not taken from the input 
to the AF amp is done for the K2 and K1.. too much digital noise... but it 
is taken from the OUTPUT of the AF Amp via a 50:1 voltage divider (47k and 
1k) to ensure that we didn't overdrive the PLL.

I'm working on a set of KX1 installation docs which will be INCLUDED in the 
general assembly and alignment docs for the CW Tuning Indicator. I'm also 
working on installation docs for the K1, but we still need to hammer out 
the best way of installing the LED itself WITHOUT having to drill a hole... 
one option will be to illuminate (with a contrasting color) one edge (or 
possibly a corner) of the LCD display. But this remains to be solidified a 
bit more. I do have connection data available as well for the asking.

73,

Tom Hammond    N0SS