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Kenwood TK-6110 / TK6110 mods for 6 meters and 10 meters
The TK-6110-K2 covers 35-50mhz
KPG-59D to program.
Freq area in codeplug file: $1840-$1A3F
Here is how to make a TK-6110-K2 work on 6 meters.
As an added bonus, it will also work on 10 meters too !
First make sure you have a TK-6110K2 as its TX filter drops off past 54mhz. A K1 model might have a lower filter cutoff freq.
With the KPG59D software, go into Edit then Test Frequency. Set them up like this:
Ch 1: TX/RX 42.60 mhz
Ch 2: TX/RX 35.10 mhz
Ch 7: TX/RX 50.00 mhz
Ch 11: TX/RX 54.00 mhz
Ch 12: TX/RX 29.50 mhz
(If it won't let you enter 29.50 and 54.00 mhz, use the KPG59X program mentioned below)
Write the new test freqs to the radio.
The following procedure will re-tune the frontend varactor to handle 50-54mhz. The important setting here is setting "sensitivity" to 255 at 54mhz. This prevents a binary rollover from the CPU to the DAC which feeds the varactors, otherwise the DAC will suddenly shift the frontend passband down to around 30mhz when the radio is above about 51mhz. Also, setting it to "134" for 29.50mhz will make the radio work on the 10m band ! (The binary rollover situation is the reason why you can't simply back out the transformer slugs).
The only caveat to this is the front end passband will be a little wider, and there might be about 3db less sensitivity around 40-44mhz. Keep in mind these are the settings which worked for my particular radio, to really do this nicely you need to sweep 29-54mhz into the antenna jack and evaluate the filter output with a spectrum analyzer.
Go to Program then Test Mode, select channel with the up-arrow key, press F10 for tuning mode, then select "Sensitivity".
With the left/right arrows, set the "Data" value to these numbers (and press ENTER then ESC when done):
Ch 1: 134
Ch 2: 134
Ch 7: 213
Ch 11: 255
Ch 12: 134
Write these changes to the radio.
Now program the radio. With the stock KPG-59D you can put in freqs 10mhz less then hex-edit the file to move the freqs from 40mhz to 50mhz. The freq area in the file is $1840-$1A3F. An easier way is to use my modified version of KPG59D which I call KPG59X. This allows you to directly enter in 6-meter & 10-meter frequencies. KPG59X is available here: http://www.interceptradio.com/files/misc/kpg59x.exe
KPG59X is designed to be installed with the KPG59D files. Install KPG59D then put KPG59X.exe into the folder where KPG59D.exe is. Then run KPG59X.exe instead of KPG59D.exe If you don't already have KPG59D, you can get it here: http://enlace-soporte.com/descargas/kenwood/
Here is how to connect both a 10-meter and 6-meter antenna without a duplexer: http://www.interceptradio.com/files/wiki/diplex-low-band-antenna.pdf
Personally I found the above method to have a little higher SWR than I wanted so I used a Comet CF-360B duplexer instead.