Kwik-Fli, Slow Build: Kraft KP-4B Radio System

Kwik-Fli, Slow Build Blog Series header graphic. With a close-up of the model's engine at center, the graphic is done in orange and blue.Built to compete in the Vintage Radio Control Society’s Concours d’Elegance event, Beppe Fascione’s Kwik-Fli Mk. II it is meant to be as accurate a reproduction of Phil Kraft’s 1965 Kwik-Fli Mk. II as possible. But, does that mean he’s going to fly the model with period 1965 radio control equipment?

Beppe uses an authentic Kraft KP-4B Radio System, circa 1967, which was very similar to the Kraft KP-4B system that Phil would have used flying in 1965 – and later used to fly the Kwik-Fli Mk. III. However, Beppe’s has as a secret – hidden in the 1967 gold metal case is a Futaba FG circuit board.

Close up of a Kraft transmitter in a gold metal case, with the early Kraft circuit logo.
Beppe’s Kraft KP-4B transmitter.

According to Beppe, “My KP-4B transmitter is probably 1966-67. It was in quite good condition, but I couldn’t trust the electronics on the PC board. So, my dear friend Pete Waters, the KMI guy, removed the old PC board and replaced it with a Futaba FG board, extremely reliable and equipped with Reverse Switches!!! When dealing with Vintage radios, two things are usually missed, the ATV and Servo reversing!!! In order to cope with the absence of Servo reversing you have to plan well in advance how to install the servos and the pushrods. The last resource is to reverse the wires at the servo pot and the servo motor (not so easy…). So, Servo reversing was a real blessing. In the end, I had a Futaba Transmitter in an old Kraft case, the airborne system was totally Futaba, and I never had a glitch!!!”

The open back of a Kraft KP-4B transmitter modified with modern Futaba equipment.
Close-up of the circuit board in Beppe’s Kraft KP-4B transmitter.

Next post: October 15, 2020
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