Ben,

I am never impressed and never surprised!

In the german transmitters Bellaphon, Variophon etc. we see the dual function stick on the right side and a (left/right) single stick on left side.
In the Telecont 9 transmitter the dual function stick seems to be mounted on the left side. In that case it looks normal to use left hand for elevator and rudder and the singlestick on the right side for aileron.

How did they fly the systems, how did fly Frits? I don’t know, maybe Frits did have a custom built.



Blab bla about Old Radio sticks?
We Dutch engineers can show you how to handle some grease without any reduction of the reliability.(LOL)

Here we are, look the picture.

Quality of the sticks of course was highly depending of design, material choices and manufacturing.
To show my old proportional dual stick.

About looseness between the stick extension and the yoke

After many many years of usage I can measure a play of 0,04 mm on the main mechanics, (a little looseness between the stick extension and the yoke) on a total travel of 26 mm. it is a hysteresis in centre position of 0,15 % to compare with 3 bits of a digital 2024 resolution, when count from centre position of the stick this is 1,5 digit of the 2024.

Design points:

The most important functions, ailerons and elevator do have the longest yoke and that is 28 mm.

The yoke isn’t a exact bow (see blue arc) so the point of contact of the stick extension in the yoke is different on each position of the stick to reduce wear.

The shortest yokes (throttle and rudder) does have a flat surface of the stick extension in the yoke to reduce wear, play is about the same.

We as pilot do recognize the position of the stick by the feedback force of the spring and the location of the stick by thumb or fingers, so also noting to do with that 0,15 % hysteresis of stick travel in the centre position, so in my opinion there is not much (I do not say "no"!!) negative influence on quality of pilot input.

Much more important is the centralization of the stick potentiometer and that does not have anything to do with this “play” and is 0 of all functions and does not change (see red circle on the picture).

The quality of the ball bearing is very important, and the only feed through to the outside of the transmitter case and that is important to keep rainwater and dust outside the casing of the transmitter. For this simple reason I prefer these sticks highly in real bad weather conditions above the modern stick.

Me as an instrumentation engineer always did have all kind of “greases” on different locations of the transmitter, so not only the outside grease but also on the stick extension and yoke and the ball bearing.

Each stick has two potentiometers so lowest possible amount

We can adjust the friction of both functions, for example to block the throttle position (a little) during aileron input.

The outside grease on the transmitter case is a result af the engine oil we did use in the past, the Dutch name is “wonderolie” the wonder effect is, it let underestimate my enemy in my pilot capabilities during war we all did call "Pattern flying".

Cees