Aerotron - Anyone have information

[Carl]

Over a year ago I'd picked up a set of Aerotron transmitters. Haven't been able to find anything out about them. Another small cottage industry producer? I'm sure one of you knowledgeable chaps on the forum probably know something. Here are some pictures of what I have:

This blue one is a 2 channel

This red one is a 4 channel with one auxiliary switch channel

And this black one I really like. Again 4 proportional channels and this time 2 auxiliary switch channels. It has a really nifty battery meter.

On top there's an extra switch labelled 'GEAR' - would that be a separate channel?

Any information would be appreciated,
Carl

[mode1]

Made in Dudley West Midlands, and Telford by the late Martin Walsh and myself, and yes a small cottage industry operation.

Cases were made by SLM Cheltenham from the popular RCM&E pattern. Red/Black/Blue cases were somewhat unusually powder coated. The cases were originally anodised in red and gold finish, but the company who did them failed to provide the finish required. They were scrapped and another batch produced by SLM.

Sadly Martin Walsh was killed a few years ago in a micro-light accident. Not just a very clever bloke, but a real gentleman too. There's another post showing a different Aerotron TX version, one I've never seen before, presumably an early one Martin produced this for himself. Aerotron= Aerotronic Controls Ltd Telford.

Never made in great numbers, but using all UK sourced hardware and sticks, (again SLM Cheltenham).
The black one in this post is a one off Martin made for use with helicopters which he was a great fan of at the time (around 1993). Worthy of note is the positioning of the sticks with trim levers to the outside. Martin and I agreed this was logical for this type of stick which used fairly high friction slider trims. Most of the pcb's were made in house by myself. Martin possibly had a few specials produced in Telford as the workshop he occupied was adjacent to Telford Circuits.

There are still several of these transmitters in regular use which are owned by my pal a vintage and diesel fan..... "the Diesel Dave". Encoder was based around the popular Philips/Signetcs NE5044. Oddly enough every transmitter was produced for mode 1. (easily converted to 2)

Hope this is of help.

Mode 1

[Carl]

Thanks 'Mode 1' for the information. It's nice to get a little history behind these transmitters.

I must say, they are really nicely put together. In fact these are so clean (inside and out) that it'a as if they've never been used. I'll take a few internal pictures later and post in this thread.

The 2 channel one (blue) is missing the RF board, so if you (or anyone) know of or have a spare one then it would be nice to make this transmitter complete.

The other Aerotron you mentioned elsewhere on this forum was posted by myself. I was offering it for sale, but it will probably be nice to keep it together with these three and restore it.

Carl

[mode1]

Missing RF board? That's no problem.
The original had 2N3866 power amplifier and 10mm sized coils with 7mm for driver and oscillator stages.
Martin used a really neat RF power design which was in fact from Toko coils Japan design sheet.
Inductors are becoming as rare as rocking horse manure these days.
I still have around 80- 2K159 Toko coils, the other bits are all bog standard.
Also left over from some more recent retro conversions are a couple of complete Micron RF boards which would be compatible.

Regards,

Mode1

[Carl]

Here are some inside shots of the transmitters:

As can be seen there is no RF board - the wires left loose for it. I assume it would have been mounted between the two stick units a bit like how the pcb is mounted on the red one?

This one looks complete inside with a single board for Encoder and RF

As a one-off Martin still did a very neat job

What I'll do is PM you 'Mode 1' to organize something for the RF on the 2 channel transmitter.

Carl

[Carl]

Thought I'd post a few more pictures of the other Aerotron I have:

This transmitter is very heavy compared to the others - I think it was 1.2 kg

Looks aged inside

The RF board has a screened section where the crystal plugs in

Here is the Encoder - you can make out letters over the little switches R, E, A, M for each channel designation (picture upside down)

Carl

[mode1]

Both red and blue transmitters appear to have commercial boards installed, these are not original Aerotronic.
It is possible the boards were custom made to fit but unable to identify them by brand. Maybe someone else can identify them? They certainly do seem to be high quality and comprehensive with numerous mixing functions specific to helicopters.

The large board with centrally etched AC is one of Martins early boards made for his own use, note the numerous track modifications.

The blue transmitter has an original encoder made by either myself or Martin, however no two channel version units were made (that I'm aware of). All TX's were either 4 or 6 function and supplied mode 1. This encoder has simple servo reversing by turning the applicable plug round. 4 main functions were reversible.
Encoder is held in end cheek slots. The RF board was fixed between the sticks. These date back to late 80's.

Regards,

Mode1

[Carl]

Thanks 'Mode1' for all your insight.

So it looks like someone retrofitted different boards in a couple of the transmitters. Perhaps explains why they are so clean inside.

Carl

[mode1]

Those large green boards seem to be very comprehensive and made with heli's in mind. The boards have numerous LM324 op-amp packages presumably for mixing etc. They really are very nicely made, and looking at the RF section, a quality job, hence these boards are worth keeping as they are.

Mode1

[Carl]

Yes, I agree and will be my intention to keep them as they are. I'll just finish off the blue 2 channel one with an RF board.

Carl