Radio Control

[tedp]

Apart from the fried charger circuit it seems you are doing remarkably well for an 'electrics illiterate'.

Hope your hip operation goes well. It's rather a routine job these days but still it's an uncomfortable business. Good luck!

[gtmspyder]

Thank you all for your good wishes. :-* :D

It's nice to know that my posts are being of some use to other members, I'm not exactly electrics illiterate, but I am electronics illiterate, and can only do what I do, by following a circuit diagram, descriptions and other pictures posted, with slight modifications to what I see, if I think I can devise what to me seems a better solution.

One has never done learning, and I am receptive to any suggestions from others on here from whatever source.

I don't think the hospital will let me take my toolkit and soldering iron onto the ward with me, so you are going to have to wait for any further adventures to do with the "Glen Ogle Light Railway". ;D ;D ;D  Unless I can get that intrepid reporter from the "Killin Times" to keep you updated in my enforced absence. ::)

Kind regards,

BrianT.
 

[petersmith1942]

Brian
just to be clear my reference to electrical illiterate was to me, not you. I could not read a circuit diagram to save my life but from your photos I plan in due course to build a battery powered loco
Best wishes once again
Peter Smith

[gtmspyder]

Never entered my head Peter ;), I'm as illiterates as the next man when it comes to electronics, my only saving grace, if any, is the fact that I do have electrical training, but only in the stuff that can kill. ::) :D

Kind regards,

BrianT.

[Paulc]

Hope the operation goes well, Brian and that you are soon up and about again.

Best wishes

Paul C

[gtmspyder]

Hello all,
well as you will have worked out, I am not in hospital with one leg hung from a gallows, and family members peeling and feeding me grapes at regular intervals. :D

I have been in hospital, for the most part of today from 7am until 3.45pm, but the operation had to be cancelled as the person being operated on prior to me, had complications, and the Surgeon ran of of daylight I think.

Any way, here I am to lighten your day, with my erudite wit and good humour, well, I think that's what I do,...............where's my coat?

So, until I get the next letter offering a place, I am back to constructing.

Here is a direct request to Frank. for help please:-

As you all know, I have documented all my work on here, stage by stage, and I consider I have reached the stage where the connections to the transmitter PCB can be made, I have ordered online some 3 pin socket skeletons which are made up into 3pin sockets that can be pushed onto the 21 pins of the transmitter PCB, to allow the transmitter to be easily removed should it be required.

So, what do I want of Frank, basically to confirm what I have done, looks ok, and will work.

I have contacted Del Tang, the designer of the transmitter and receiver via email, and laid out exactly what I have done with references to the drawing, and here is a copy of my Email:-



Hello David, I

[Frank]

Hi Brian,

Sorry to hear your operation has not gone ahead, after all the preparation and so on it must be a bit of a let-down.

David T is usually pretty quick to respond but I will try to answer your questions.

The TX you are using is not one I have built but it looks very similar to mine, just more knobs.

I can't really check your wiring from here but one thing I did notice in the photos, it looks as if you have connected the red common that runs round all the controls to the 9v battery whereas I think it should go to the 3.1 v rail.  More of this below.

Answering your questions, the battery shown is the 9v battery and the switch in the 0v line from the battery is indeed the one with the LED in it.  You do need then to connect the other pole of the switch to the 0v on the circuit board, and the 0v line that you have run around the controls.

Incidentally, the board has three rows of seven pins.   All the bottom pins are connected together on the board so any will do for the 0v connection.   Similarly all the middle ones are connected together so you can connect any to the 9v supply.   It is only the top row which are the input/output terminals that are separate.   (This is because the board it is built on is basically an aircraft system intended originally to drive servos and these pins are the servo outputs, so in that application each set of three contacts needs the connection to the power supply as well as the signal. )  So you can connect to the board with three 3-pin sockets, one on one end connected across all three rows to pick up the power connections and the first signal, and the two more just connected to the top row of signal connections.  Hope is makes sense.

The positive supply works like this.  The 9v supply from the battery just goes to the transmitter board.   As I explained above, this can be any of the middle row of pins.   There is a regulator on the board that drops this to 3.1v and you pick this up on the little pad on the board indicated on the diagram.  It is the right most of a row of three pads.  This 3.1v supply is what you connect to the red line you have running round the controls.  It is the top rail on the circuit diagram.   So you have to solder a fairly thin flexible wire to the pad on the board and connect this to your red line running round the controls.  This is probably the most difficult bit of the whole process in terms of soldering.

There is indeed no mode or trim switch nor any components, I just left these unconnected and it works fine.  I suspect that if you do wire through the switches to the power rails then the transmitter will not do what you want it to do but beyond that I can't really comment, so I suggest you remove these connections and leave pins 7 and 8 disconnected.

Hope this helps

Frank

[Frank]

Brian,

Just as an aside, you mention wiring up the three pin connectors, I don't know if you have these yet but usually these come ready wired so you don't have to wire them up, you just connect the other ends of the wires into the circuit.

Frank

[gtmspyder]

Hello Frank, thank you for your very helpful reply, you're a star.

It was very useful to know that the 1st and 2nd row of pins were all commoned, I had worked out how I was going to layout the plugs I was going to assemble thinking the pins indicated by the circuit designer, were the only ones to use, and now that I have your information, the layout will be so much easier, so that's one positive.

Here are the components I have purchased to make my plugs that will plug straight onto the transmitter PCB rather than solder to the pins.



Here are plugs I have made up, plugged onto the PCB, I have made up 3 plugs and are configured as two horizontal, picking up pins 1 to 6 , and one vertical picking up pin 7 on the top row, and positive and negative pins below.



The next picture gives a side view of the three plugs and there configuration, but I would like you to note that I have added another socket to the PCB, between the circular end of the capacitor, and the PCB board pins.  This is to facilitate the connections to pin8 (as designated on the PCB) and the 3.1 volt output to the control circuit. As can be seen from the picture, the two pins of the Header assembly I am using to form the additional plug and socket are spaced just about right to pass through the wire holes where you are directed to solder the additional wires to, the six pin header was cut down to just leave two pins of the header assembly, which were pushed through the two holes in the transmitter PCB, carefully solder in place, because the holes are extremely close together, and easy to bridge with a blob of solder.and the excess length removed with side cutters.





This shows a full 8pin header, and a cut down section of a header to make a 2pin plug.  The headers will plug into each other so can be stacked if required, so can easily be cut up to make plugs and sockets, which is what I have done.
The two wires I have stripped the end insulation off, twisted and run solder over them, then cut them to length, and pushed them into the holes designed to accept the header pins.



They are a good interference fit, but just to make sure they are not accidently displaced, I have run a little superglue down into the wire hole to secure them.      



The red/black wire from the battery press stud connector, has been unsoldered from where I originally incorrectly soldered it, lengthened it with white/black wire ( I am running out of alternate colours, and as I all ready have a red and a red/black in use, I used white with a black marker pen mark.)  and pushed this through the harness sleeving, to be connected via the manufactured plug outlined above, to the pin 8 terminal on the PCB.  I replaced the removed red with a new Green/black wire for the same reason as above, and this has gone to the manufacture plug as the 3.1v feed to the internal box components.  Thank you Frank for pointing out this mistake.



It's a little hard to make out the green/black replacement for the red, but it is there if look carefully.





Here is the circuit diagram again, and I am a little uncertain what to do with the mode switch and trim switch circuits.  At the moment, they are hard wired through the switch positions as these are not used.  Now if they are used, does whatever happens happen, when the switch is open, or when it is closed.  If it happens when the switch is open, then I cannot see why wiring it through the switches will make any difference to whatever, but if it happens when the switch is closed, then I have effectively permanently closed the switches.



Frank in his ever helpful reply said:-........"There is indeed no mode or trim switch nor any components, I just left these unconnected and it works fine.  I suspect that if you do wire through the switches to the power rails then the transmitter will not do what you want it to do but beyond that I can't really comment, so I suggest you remove these connections and leave pins 7 and 8 disconnected.

If I do not use position 8, I will have no 3.1v connection to the LED,  and if I do not connect to pin 7, I will lose a supply to, or from one of the direction switches, so I am in a quandary.

I know Frank has not assembled this particular circuitry, hence my posting the supplied circuit diagram, because he understands what is supposed to happen, whereas, I am simply trying to follow instructions.
Help again Frank.



Well until I get some help from Frank, that's got to be it for tonight.

Kind regards, and thank you for your patience in reading through this rather long post.

BrianT.

[tedp]

Hello all,
well as you will have worked out, I am not in hospital with one leg hung from a gallows, and family members peeling and feeding me grapes at regular intervals. :D

I have been in hospital, for the most part of today from 7am until 3.45pm, but the operation had to be cancelled as the person being operated on prior to me, had complications, and the Surgeon ran of of daylight I think.

Any way, here I am to lighten your day, with my erudite wit and good humour, well, I think that's what I do,...............where's my coat?

So, until I get the next letter offering a place, I am back to constructing....

You must simply love modern health care! Anyway glad you're back again.

[Frank]

Hi Brian,

Fitting an additional socket is an excellent idea.

I have checked my transmitters and you are right about the LED connection from pin 8.   What I did was to connect the pin 8 to the LED in the switch via a 220ohm resistor, as the drawing, but left the mode switch out so it is open circuit.  This allows the board to control the LED which indicates the status of the transmitter.   If you leave a short in place of the mode switch then the transmitter will have a permanent signal on this line and this will I think prevent it from working properly.  You will also have the LED permanently on.    I did have a 220 ohm resistor though which I fitted here as per the diagram, I think you said you did not have one?  It certainly needs one.

The instructions with my kits said that the switches for mode, trim (and also reverse which I think you do not have, I think it may reverse the sense of the controls) are not normally needed.   I took this to mean you simply omit them and leave the circuit open ie not connected.

Frank

[gtmspyder]

Thank you for your condolences Ted, it was a bit of a bummer, but all the staff were very considerate and looked after me, and after all, it is not fair to blame them for the systems inneficiencies.

Regards,

BrianT.

[gtmspyder]

Hello again Frank, thank you for your quick reply, I have looked at my wiring, and found where I can cut the white/black wire in such a way that it effectively removes the shorted out switch, and I can also insert the 220ohm resistor at the same spot, which was supplied with the kit, although my instructions did say that it was not strictly necessary, which was my only reason for not fitting it in the first place, doh.

Well I think you have guided me nearly there Frank, thank you very much.

I've got the Lipo battery to fit in the coach now, with it's associated charging socket somewhere on the coach body, and the leads with on/off switch, to run to the loco, via I think one of the tiny battery plug and sockets which I purchased extra from Hobbytronics, then there's only the receiver to connect to the motor terminals and we are away.

I don't think I am going to isolate the wheel pickups from the motor, I can't envisage any harm coming from having the wheels live to a dead track can you?

Once again, thank you for your help.

Kind regards,

BrianT.

[Frank]

Hi Brian,

I suggest you do isolate one side of the motor, for two reasons:

You might have a short somewhere on the track eg due to a point contact for example and it would short out the motor driver.   If you drive the loco on a stretch of track with a set of points somewhere set against the loco, for example, the two rails are shorted by the point.

Also you might want to run it on your or someone else's layout with power on at some stage.

It's very easy to do.  The long metal strips on the chassis are the pickups.   There are two plastic clips, one is at the end of the long strips.  The other one covers the place where the strips meet the motor contacts which are under the long strips.   Lift this plastic clip carefully.   Pull one of the motor contacts carefully outwards from under the long strip and bend it upright.  Put the plastic clip back and you are done.   Connect the radio output to the motor contact you have just released and on the other side to the long metal strip.

Richard has some very nice photos on his "NP Baguley-Drewry goes RC" thread on NGRM online.

Frank

[gtmspyder]

Hello Frank, thank you for that bit of info, I had not thought about the track as being a danger if fed from the loco wheels, so I will do as you suggest and disable the pickups on one side.

I have just tried to post a long report to you, but when I posted I got the message someone had posted something that I might want to read before continuing to post, which I did, but in doing so, I have lost the very detailed post to your good-self unfortunately, so to make any sense, I am going to have to type it all out again, but in essence, it was basically saying that the unit did not appear to be working.  The on/off LED was not lighting now at all, although earlier in the build it had. 

The LED on the transmitter board was flashing 13 times when the unit was switched on, and then stopped, but some times resumed and continued apparently for ever, but I did not test to destruction. ::)

I have fitted the 220 ohm resistor, and removed the shorting wire that replaced the switch so that it is now open circuit.

Turning any of the four pots has no effect on anything.

Switching any of the S.P.C Over switches has no effect.

Pressing the bind button switch causes the PCB LED to dim markedly.

With the 3.1v wire and pin8 wire disconnected from the PCB, the board on turn on, flashes 13 time, pauses, then continues flashing forever.

With the 3.1v wire connected to the PCB, exactly the same happens.

With the pin 8 connected, ditto the above.

That's about as much as I can glean from playing about with switches and connections on the PCB board and controls.

Interestingly, the supplied notes only tells how to set up the receiver using a joystick controller, not how to do it with the transmitter.

If from the above notes, I cannot make any headway, the I will strip out all the wiring and start again being even more carefull with the wiring.

I will replace all the resistors with new, as I will be unable to recover them from the existing circuit, and I will replace the on/off LED indicator switch with a new one, as I was not impressed with the originals quality, and I may have damaged the internal LED in some way as it did originaly light.

In the mean time, until some incoming mail is able to shine a light on my confusion, or not, ::)I will start work on motorising the loco, fitting the receiver, and installing the Lipo cell into the trailing power carrying carriage

I'll be back later,

BrianT,