Fox Delta ST2 interface for driving AC motor rotors (2025/10/13)
The Fox Delta ST2 rotor controller was given to me along with the IC-820H.
This single unit can control both the horizontal and elevation rotors.
However, the output is DC open collector only.
It seems to be a product targeted at the YAESU G-5500
This circuit alone cannot switch the AC motor rotor on and off.
The common terminals 4 and 5 of SW-L and SW-R must be turned on with a relay.
Therefore, the open collector output of ST2 operates a relay (SRA-05VDC-CL) to drive KR-500 and KR-400.
I used a stock Janome circuit board and the SRA-05VDC-CL relay and terminal block I purchased.
I purchased it through the usual Philippine online store, Shopee.
The only wire I could buy at the local parts store was thick, so the wiring isn't very neat, but it's complete.
I tried to put the interface I made into the Kenpro KR-500, but there was no space.
The large electrolytic capacitor that is attached sideways is a nuisance
So I moved the electrolytic capacitors to make room for the interface board.
A nicely fitted board.
Miraculously, I had some 30mm spacers in stock, which helped me to mount the interface board.
The broken potentiometer (B500Ω) and 6.8V Zener (BZX55C6V8 1/2W) should arrive this week.
Once that arrives, the repair of the Kenpro Elevation Rotator KR-500 will be complete.
I also had a friend send me a Kenpro KR-400 rotor that I won on a Japanese Yahoo auction via EMS.
It will probably arrive in about a month to 40 days.
This one also needs to be repaired as the potentiometer seems to be broken.