Nimit Hongyim (นิมิตร หงษ์ยิ้ม) Naiyim Garage นายยิ้ม การาจ: Modified the Old KENPRO KR-400 and KR-500 to used with My Arduino controller

FARS (Foothills Amateur Radio Society) have the old AZ-EL KR-400 and KR-500 rotor set that we used for Field day in every year, It was kind of rusty and dusty, I brought it to clean up then wash and then modified the bracket and adding relay because of there have the AC-24 voltage Motor and cannot be used with H-Bridge controller like DC-Motor.

After Tested with the new controller then I found that Original KR-400 has the scale which indicated North (0) at the center scale, it will confused the user if the Rotor turn from 0 to 360 Max then I start to modify the scale to match the real position.

SCALE Part :-
For the KR-400 to display 0 - 360 not the 180-0-180 as the original Kenpro designed then It need to scan the original scale and then cut and paste then move around the number of degree to have South as Center of the scale to match 0 volt and full scale as 5V then I used the Paint-Brush program to edit and print the actual size to match the scale plate.

(Final )South Centered scale for KENPRO- KR 400 Controller

Use the Mouse Right Click the "Save As" then open with MS-Paint brush program for printing.

Original KR-400 North Center Scale

Paint Brush program used for edit and Print to my Color laser printer. the hard part was print to be the same size as original scale, I did try the Window view print but it seems hard to control but if I use the Print-Brush program to print directly to printer then I got the right scale. that was some trick.

Removed the Panel Meter

then used the back-side of the scale aluminum plate to glue the new scale with my paper print-out.

All Done. Look like never has been modified :)

Controller Part:-

First, I want to use the solid-state relay or the "HEXFET" PVG612PDF from IR to controller AC motor but I checked price per part if I will order from Digikey or Newark around $8-$ +S&H and I will need 4 of them, well cost will be like $34 USD and since this is not the my controller and I build for my HAM Club so then non profit at all and need to be as conservative budget as perfect as I can then I found the many of my 12 V relays laying around my old component box so then I modified the relay board to be used for 2 Transistors which will receive active "LOW' level logic from my Arduino controller and the add 6 Volt 7806 for the POT encoder voltage because of the long cable dropped the voltage below 5V when it fully turn to maximum. All worked up pretty good, Need to do paint job with my Controller box (Powder Coating) . I was thinking about build the nice Kit for other Ham too, let see if I have time left.

Completed with Both AZ-EL box modification test and worked..

Serial Arduino board was used in this project due to unstable USB sometime on sleep never wake up not like direct serial port with MAX-232 pure and simple work as good as you need. ATMEGA328 chip become very cheap now a day, in the previous project that used 16F84 already obsolete and used Assembly language to program also too old to debug and LVB tracker that also used 16F876 also used very old C- compiler then I found the Arduino more fun to program and play as I can say that "even CAVE Man can do it" also I have seen 8 year old program Arduino then why not jump in and found how easy and so much function library that I can play. The Cost of the chip if you buy from Digikey or Newark $2.89 USD Blank no boot loader and I have programmer from $13 USd so I can do much more project as cheap as I need.

Feature :Remote controller with Small SONY Car radio Remote. Nice!!!

at the back of this controller that I used RJ-45 standard which can be used either one of them wiring as parallel and can be connect direct to DIN 8 connect to Yaesu 5500

Tested and work pretty goodwith My Arduino

I used RJ-45 because easy to find around me in my office and it free also have 8 wires which perfect and twist wire help to reduce the noise from AC motor as well. the hard part was cut the hole to match the square RJ-45 female in PCB inside. not pretty but it was not that bad.