[TenTec] DDS PTO replacement for old Ten Tec rigs

[Curt Benjamin]

Guys, since the N4YG DDS is no longer available and too expensive anyway, I have been exploring the idea of making my own. So far, I've taken the Arduino code to control one of those $8 AD9850 DDS modules from China to tune from 5 to 5.5MHz but I haven't found a way to add an RIT line to it.
What I'm thinking might work is making something like a 2MHz xtal oscillator with a voltage-controlled shift line using a varactor and mixing that with the Arduino/AD9850 DDS that tunes from 3 to 3.5 MHz instead.
I don't think any of these frequencies would pose any problems in either the DC receiver in the C21/22 or in any of the superhets of the other various models but I'm not sure. What do you folks think? Is that a good scheme or should I change the frequencies. I picked 2MHz because it's available in a off-the-shelf crystal. Thanks.
Curt, K8AI