Simprop SAM & SAM Gold

[tiptipflyer]

Sorry,
no infos on the Super1. Never seen on life, just on pictures.

SimpropDigi.pdf

(3.61 MiB) Downloaded 190 times

SimpropDigi2.pdf

(5.07 MiB) Downloaded 165 times

That´s about in on Simprop.
Have fun
Frank

[stuart mackay]

Brilliant stuff Frank, They are really useful as they have the circuit diagrams in them too. Have re-posted one on the Digi5 thread

[stuart mackay]

Just to show you how you would build up the operating features of the SAM, here is the Acapulco module introduced to celebrate Hanno Prettner winning the World Champs in guess where?
It added an extra two channels to the Tx (channel 6 , aileron right and channel 7, flap servo)

The module contains:
Delta- V-tail mix
Aileron Dual Rate
Aileron and flap differential
Landing and camber flap adjustment.

It fits into the lower right hand switch bay on the Tx front panel.

It cost around 80 Deutschmarks back in the 80's

[PaulJ]

This thread prompted me to have another go at converting my old Simprop SAM. Phil sent me one of his new all singing, all dancing 7 channel encoders and after a bit of experimenting with resistors and the separate trim pots, it all works perfectly........ except for the Elevator trim . The main stick pots are 5 Kohm and the trim pots are about 2.5 Kohm and, having first tried to add resitors in the trim pot line (as shown in Phil's instructions, I ended up getting the most useable result by not adding any resistors at all and keeping it as it was........ Throttle, Aileron and Rudder trims all work perfectly but, though the elevator operates as it should, the trim wheel does nothing. As far as I can tell the trim pot is OK and the wiring between the stick pot and it's wiper and the trim pot seems to be intact....... Has anybody got any suggestions ???

Paul

[stuart mackay]

Well done Paul, guess what I was doing today also!?!
Trying out a FrSKY JR module which I am adapting to suit. I am staying "analogue" and retaining the existing encoder, as I have the OE Acapulco and dual rate/expo modules to fit in there and all the electronics on the silver Tx are brand new.
Have you modded the antenna mount yet?

[stuart mackay]

As far as I can tell the trim pot is OK and the wiring between the stick pot and it's wiper and the trim pot seems to be intact....... Has anybody got any suggestions ???

Paul

Sounds like we need a view from Mike Kitchen or one of our Dutch or German colleagues to chime in on this?

[MaxZ]

....having first tried to add resitors in the trim pot line (as shown in Phil's instructions, I ended up getting the most useable result by not adding any resistors at all and keeping it as it was........

Hi Paul, I sold my SAM on some time ago, so I cannot check anything in real life. But I am wondering, the stick pot and trim pot wipers are wired separately to the main board, Phil's instructions ask for them to be combined by coupling them with a resistor, how can any trim work if you "keep it as it was" ?

Cheers,
Max.

[MaxZ]

I do have some remnants of the stick units from an SSM Contest, which I believe are the same sticks as used in the SAM. The resistor tracks have gone, I gave those to another modeller somewhere in Germany, but I do have the trim pots.
The way those trimpots are fitted make them prone to errors. The body is clamped in a plastic C-clamp with the trim lever attached as one piece. Theoretically you can rotate the body in the clamp, but it is a tight fit. The other potential error is the way the wiper is fixed to the stick base, which consist of a cross-shaped hole in the pot axle, slipped over a cross-shaped protrusion on the stick base. Again theoretically, someone could have dismantled the trim pot, and mounted it rotated by 90 degrees. It will still seem to work properly (I checked), but it will give totally wrong resistance values.
By the way, I checked the pot values, total resistance is 5K, the wiper varies from roughly 2K to 3K from stop to stop. So the 2.5K you measured is either a difference between SAM and SSM, or an error. Did you measure the outer pins of the pot itself, or just on the wiper wire?

Cheers,
Max.

[Mike_K]

Has anybody got any suggestions ???

Paul

Helping you with converting a radio is a bit like telling you "how to suck eggs", you've converted as many sets and are competent as anybody on the forum. If it helps, I have got an untouched Simprop SAM on my bench at the moment, so if you want me to check any resistance values etc just ask.

What circuit are you using to wire the trims to the main joysticks? The Simprop SAM joystick pots are unusual in that they are custom wire-wound and the joystick moves them full travel, ie they go from full 5V to ground (most joysticks use commercial pots and only move them around 70 deg of the full 300 deg movement). But if the aileron and rudder are working, then there is no reason why the elevator won't work as well. I guess it's a case of checking the voltages across the trim pot with the set powered up, you should get a small voltage across it that should vary when you move it. If the voltage doesn't alter when you move the trim pot, then unsoldering the elevator wiring and checking the elevator trim pot with a multi-meter to ensure the trim wheel is actually moving the wiper. I can't think of anything else without seeing it.

Mike

[stuart mackay]

Good progress made today and with FrSKY JR module hacked and wired in. Using existing encoders and mixers on the Tx.

Fitted a new Eneloop battery with a plug connection to separate when not in use.

Wired in a Simprop 3 position switch into channel 1 and the Acapulco module looks after the aileron differential and flap mixing, but sorting that lot out is a job for tomorrow. Will need to look out for a linear slider me thinks to operate the flaps/airbrakes.

Aerial is in one of the module bays at the moment, but need access to a lathe to bore out the OE moulding to accommodate. But this will be destined for my Prettner Curare when the opportunity arises.

Thanks to Peter Gruchot and Mike K for their help so far!

Further inspiration from Paul Jefferies and I managed to get the 2.4 Gig antenna from Spektrum (on left FrSKY on right) located where it is supposed to be today.