CTCSS mod

Yaesu FT-221R CTCSS mod

Please read the update on the bottom of the page.

Because most of the dutch repeaters now need CTCSS to operate, I added a CTSSS module from the same model I used on the Kenwood TS-700G CTCSS mod. The supplier and more info about the module can be found on this page : http://www.rronline.nl/pd0aqk/ctcss/index.html

I didn't have and don't have intentions to use the fixed frequencies crystal options so I used to selector switch to control the CTCSS board and select the needed frequency. On one of the switch planes of the selector I added a diode matrix to the switch as shown in the image below. On the other switch plane I wired positions 1, 2, 3, and 4 together and used it as ON/OFF .

 

I will describe the wiring in more detail later. One thing I did do was adding adding a extra lowpass filter to it get the output signal a bit more into shape and a variable resistor to adjust the output voltage to the correct value.

The company Communications Specialists (who makes SS-64 module) shows you exactly where tone wire goes in FT-221 (see : http://www.com-spec.com/insheet/ft-221r.pdf ).

With usage of the Yaesu FT-221 Service Manual, find the  MIC AMP (PB-1460) printed circuit board and insert the signal on junction of R10 (33K ohm), and R11 (22K ohm), after Q03. That's all.

I packed the CTCSS encoder with the suport PCB in to heat shrink wrap so it can be put into the rig without any problems of shortening stuff.



Not complety factory design, but it wil manage.

 


Update : The link to the CTCSS encode kitt is a dead link. But when you want something simulair like the kitt the website of the Repeater Bergen Op Zoom. They have the schematic online of a nice little CTCSS encoder :  http://repeater.hvde.nl/pi3boz/ctcss.stm

Previous page: Mode switch puls mod Next page: Var output power mod