If any one can give me some information on the Multi Decoder Switch + Prop 12 + 2 No.8370 unit I would be most grateful. I did post elsewhere, but have had no answer

First off, I have only, in the past couple of weeks had any involvement in the radio control hobby, and this posting is to help out a chap who is having difficulty in setting this unit up. I have basic electronic/ radio knowledge up to amateur radio levels, building of circuits/PCBs etc.
The unit I am refering to does not actually have the name Futaba on it but it does have robbe, which as I have seen robbe futaba on the receiver unit (FR-R118F), I am assuming is part of the same company

The question I have is regading the wiring of the switch outputs K1-8. I have two sets of instructions, but unfortunately they both seem to contradict each other.

One set of instructions states that the outputs are exactly that.....outputs.....they supply a voltage (at up to a current of 1.8A when used singularly) from the centre terminal of each switch, the outer terminals being the switched side. They also state not to apply voltage to output sockets of the decoder.

The second set of instructions uses the output sockets of the decoder as mere switches. The centre terminal of each socket is connected to the negative terminal of a seperate battery and the load (bulb/motor/pump etc) to the positive terminal. The ground side of the load is then connected back to the outer terminal of the decoder output. Two loads being connected to each decoder output.

Can anyone inform me which is correct, or are both methods correct and acceptable.

Thanks for your help in this....you never know if I get this working for the chap, you may even have a new convert to this hobby.

Regards

Neil

http://www2.towerhobbies.com/cgi-bin...p?&I=LXLZH6&P=

is this something like what you are talking about?

Sort of, but less advanced. It is a 12 switched and 2 proportional unit for an robbe FutabaF14 controller

Like
http://at.robbe-online.net/rims_at.s.../View/1&2D8370

[link=http://at.robbe-online.net/rims_at.storefront/45ae7cfa00200973271b3e0dc1460643/Product/View/1&2D8370]12+2[/link]



At the TX end

In answer to your original question it does look like "both" are correct as YOU put it.

As you are a beginner may I ask why you think you need this device? Most modelers with dozens of yeqrs of experience would NEVER need one of these.

Of note is the fact that you can only use it in conjunction with a small variety of tranmitter/receiver combinations.

Do you have a F-14, FC-16, FC-18 or FC-28 transmitter as called for?

I know the Futaba unit I posted above will only work with thier 14MZ system with the 12MZ soon to be adapted. But these are Futaba's top of the line radios.

Hi Bruce
Thanks for helping out here.

One of the sets of instructions MUST be wrong....One states DO NOT apply voltage to the switch pins, while this is exactly what the other set tells you to do.

It is not actually for me. It is for a chap locally who is in the first stages of alzheimers and needs a bit of help with getting the electrics sorted on his models.
He is doing some bloody nice work on his models but does not know much about the electrickery side of things.

As I am reasonablely capable at electronics (amateur radio etc Callsign GJ1YOT) I am helping him out.

Yes we do have one of those Transmitters, it is for an F14 Navy.

The latest model is a Motor Torpedo Boat, with a shed load of other devices that need individual control channels, from lights, sounds, anchors, smoke, guns etc etc.

I have not yet wired this unit up and checked if the switches do actually give any output or are just switches, but if I can find someone with one of these it would be great. Due to the price of it, I dont want to go and fry it...you know what it can be like trying to do someone a favour

Cheers

Neil

I've found http://data.robbe-online.net/robbe_pdf/P1122_1-8101.pdf attached to the link you gave above.

"The second set of instructions uses the output sockets of the decoder as mere switches. The centre terminal of each socket is connected to the negative terminal of a seperate battery and the load (bulb/motor/pump etc) to the positive terminal. The ground side of the load is then connected back to the outer terminal of the decoder output. Two loads being connected to each decoder output."

Can you provide the link where you saw the above?
I see no "separate" battery in the instruction link above. I DO see circuit boards labeled for polarity. Is an "Akku" a battery?

The link you found there is a link to the same instructions that are supplied with the unit.
The other instruction (I have just found out) have come from a dealer of these units who does not believe the original instructions are very good so has created his own. I am trying to get a electronic copy at the moment.
I believe Akku is a german abreviation for a battery, yes.

There is no seperate battery shown that is exactly my point, the original pdf set of instructions show units running without extra battery. and the polarity on these diagrams seem to show the positive from the center terminal of the plug.

Will have to get it plugged into a receiver and put a meter across the terminals and see what it produces

Have you tried the Futaba support forum here on RCU?

Yes, but they seem to think that as it is a robbe product it was not imported in to North America, and they cant really help, and have no data on it