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If the Tx is switched away from the Selecta position, but the Rx does not lose the Tx signal, then the loco will carry on running indefinitely at the same speed setting. I have had an Rx 6, can't remember which model exactly, that responds slowly to a change in the Selecta knob, which sometimes resulted either in slowness in gaining control or the Rx responding to throttle changes after the Selecta switch had been moved to another loco position. It is a loco I don't use except for demos as it's not a scale I have a layout for, so I have not got round to investigating it. It sounds like a problem with the Rx I think, as the Tx is fine with all the other locos, although it might possibly be because a resistor in the Tx Selecta switch circuit is incorrect or on the edge of the tolerance band, which would only affect that particular Selecta setting, or indeed a dry joint. Maybe you have something similar, the Rx is losing the Selecta setting at some point and so just keeping going at the same speed setting? Difficult to see how this would happen in the Rx though. Thinking aloud there, but it might be worth trying binding the loco to a different Selecta position. Frank

Corbs, I found that if I tried to bind the loco with a strong WiFi signal nearby, it would sort of bind to the WiFi and then it did odd things as the Rx tried to do what it thought the WiFi was telling it to do. This included not moving at all and also sometimes moving steadily along. So some form of interference may be the problem. The lack of aerial will not be helping the Rx pick up the right signal, so it may be more susceptible to interference perhaps. Giles, There is a safety feature in the Deltang system, the receiver will not "arm" itself ie start up unless the speed is set to zero, which may mean the speed channel pot being at mid point if it is assuming a centre zero speed control as they normally are by default. So this might explain why you had to waggle the sticks - it was waiting for the channel that is normally the speed channel to pass through the mid point. With any of my locos you have to set the speed to zero to get them to work. No idea about the creep though. You can calibrate the Tx to get the centre "off" in the right position on the pot, but you sound to have had an intermittent fault somewhere. Maybe a dry joint problem? Frank

Hi Corbs, Yes, solder it on. It will need a fine tipped soldering iron and some electrical solder ie solder wire with flux cores inside it. If the receiver has the heat shrink sleeve plastic cover you will need to cut this away to get to the pad on the board. The aerial can just be any fine flexible wire, nothing special about it apart from the length, it will need to be insulated wire of course. I suggest soldering it on first then cutting to length, easier to handle and easier to get the length right. Frank

Hi Corbs, Getting the aerial length right could be important. It will give the best signal and help reject interference on other frequencies. Just measured the aerial on one of my receivers. It is 29 mm long. Frank

Hi Corbs, That sounds a sorry tale! It's difficult to diagnose problems like this at a distance as it were but here are some suggestions. I don't think the change to the 3v motor would cause any problems. I have had problems like this with binding locos and lack of response when using them near a strong WiFi signal. For instance, if I try to bind locos next to my domestic PC and it is switched on then this can cause problems. Switching the PC off or simply moving away sorts it out. Once bound, though, the problem usually goes away. I think the aerial snapping off won't help. I suggest you replace this if you can. Frank

If you are worried about soldering the wires to the Deltang transmitter module, the pins take standard servo connectors so if you buy these ready wired to leads you can get by without any soldering to the pins, although there are a couple of connections to make direct to the board. Frank

Hi John, The basic idea looks good. I think adding a diode would be a good idea, although whether its essential or not depends on the circuit of the step-up convertor. You would lose half a volt or so across the diode. The 1N4001 should be OK, it is good for an amp and I don't suppose your motor will take that much current. However, a better solution would be to use a double pole switch instead of a single pole one, and use one pole to switch the battery as you have it and the other to switch the motor driver input. Often a double pole switch is not mich bigger than the equivalent single pole one as its usually the mechanism that determines the size, not the contacts. Frank

Hi Mick, My this sounds an interesting idea! I like the idea of the figure pushing it round, and am wondering about lining it up above the tracks before lowering it. Maybe some "planks" alongside the rails to guide the wheels? Your ideas on the control system look good to me. I can't comment on the LiPo as I don't know what current and voltage your motor would need but it should be OK if you do not need the step up circuit. If you do you might need a bigger capacity. The Rx will need programming to give the servo outputs I think, I suggest you talk to Micron about this as they should be able to set these up before they send them to you. As for servos, have you looked at linear servos eg http://www.micronradiocontrol.co.uk/servo.html#sm-os1300 These may be more suitable for a straight lift if you can fit one in. Frank

I'd guess the DelTang power switching circuit uses something like this http://docs-europe.electrocomponents.com/webdocs/1539/0900766b81539987.pdf The reed switch would switch it on then it would be held on by the microprocessor until told to turn off. Standby current is very low to conserve the battery. This one is only for 5v supplies as it is intended for USB applications. It would be OK for 1S installations but there must be other ones with higher voltages. Frank

Some of the DelTang receivers use microswitches but they are not latching. The receivers can be turned off by command from the transmitter, and the microswitch is used to turn them on again using a magnet. I use small switches like these http://cpc.farnell.com/eao/09-03290-01/slide-switch-spdt-vert/dp/SW03106 They work fine and can be hidden under the loco, usually behind the cab steps is a good place. Frank

I agree with Spotic's comments. We tend to talk about the details of how to implement radio control because that is where we are with its development, but that is not the real point. For me, the big thing about radio control is that it allows locos to be driven using their on board power, without relying on track power at all. This means that, just like the real thing, you turn on the power and the loco moves off. No iffs, no buts, no hesitation, no need to prod the loco or tap the baseboard to get it moving, it just moves. This gives a completely different driving experience, not just a confidence boost but a different perspective, you just think about where the loco is going. It also allows the loco to be driven at realistic slow speeds without worrying about it stalling on a dodgy bit of track. This is why when I demonstrate radio control at shows I like to get people to try driving the locos for themselves, because that is where the real difference lies. Then there are the new possibilities of weathered track, or wooden track, and of being able to design track layouts unconstrained by the need to avoid short circuits in things like triangle layouts. Not to mention the fact that you will not need to clean the track! Frank

Hi Giles, That looks a very nice loco and runs very smoothly. Looking forward to seeing it develop. Frank

Thanks Corbs! I have a demo of radio control that gets half a dozen exhibition outings a year. It includes a small 009 layout so people can try the locos out. The locos typically need recharging after 4 to 6 hours, depending on how much running they get. I have several I could interchange, so I could get by without recharging any, but I like to keep them ready to run. This means usually I need a mains lead but I do have a battery unit like the one Corbs has in case there is no mains socket handy. It works fine. There are a few 009 layouts about at exhibitions now that use radio control. Frank

Hi Corbs, Excellent video! That is a really neat installation. It looks good and it works very well! Frank

I have found that adjusting the back-to-back of the wheelsets, making it slightly bigger, helps a lot with getting the Triang stock to run through the Peco points. Easing the wagon and coach bogie wheels apart a bit is easy enough, the loco wheels can also be eased but require a lot more force to move them. Frank

HobbyKing do some round cells that might fit in the pannier tanks, depending on how big they are of course. They are more the shape of a pannier than the flat ones. If you can get the weight out! Eg: https://hobbyking.com/en_us/turnigy-nano-tech-270mah-1s-15c-round-cell.html It you are setting up some tests it would be useful to measure the current if you can. This will tell you how big a bettery you need. Robin is right, most locos need weight as much for electrical contact as adhesion, with radio control this isn't an issue so the locos can be lighter. Frank

I have converted an old design split chassis Bachmann Stanier 2-6-2T (OO). I carved enough out of the weight in the side tanks to fit a 150mAh (I think, or thereabouts) battery on each side, giving me a 2S setup, which was Ok to power the original motor. The receiver went in the cab and the switch and charging connector under the cab floor hidden by the steps to the cab - my usual place to put these. The tricky bit with the split chassis was that the two chassis castings clamped the motor and made contact with the motor terminals via short springs. I cut away enough of the casting to break the contact without cutting so much that the motor became loose. This allows the receiver to be wired directly to the motor terminals. It looked good when finished and ran at a nice speed for an hour or two on a full charge. I tested it on a club layout as I don't have an OO layout myself. I'd suggest trying various voltages with the chassis to see how many batteries you need, and take it from there. Frank

Hi Gary, Just a thought, perhaps a bit late in the day. I have for some time been havering between 12mm and 14.2mm. The advantage of 12mm is the availability of the original Triang models, especially through the 3mm Society's second hand sales, and Peco 12mm gauge track. The advantage of 14.2mm is that the track just looks so much better, and it's easy enough to build, flexi track can be assembled from Society track bases, and simple points are not so difficult. What I have found is that it is quite possible to try both. Most rolling stock is easily re-gauged from one to the other just by moving the wheels on the axles. The main difficulty is the locos of course, wheels are generally available from the Society for both gauges now, but swapping over is not as simple as just moving the wheels, as the axles will need changing as well which means the drive gear too, and any outside motion may need adjusting too. A really good start would be to join the 3mm Society and build a short piece of track (even one of each gauge) and some of their plastic wagon kits and see what you like best. Frank

Batteries mainly depend on the motor. You need to decide how many, which depends on the voltage the loco needs to run a typical speed (not flat out!) and what capacity to ginve a reasonable duration. As I said, I know nothing about the 33''s, but a fairly modern OO loco would typically need two LiPo batteries in series, nominal voltage 7.4 volts, to run reasonably and perhaps 200 mAh to give reasonable duration (an hour at least, possibly two), more if you have space. You will need an Rx6 series receiver to run this, the exact model depending on what else you might want to do. If possible, measure the voltage you need on the rails to drive the loco with the track cleaner, and the current it takes. Frank

Hi, I am not familiar with the Heljan 33's but here are some things to think about. The model of receiver you need is determined by the size and the stall current, as you say. The Rx65 is probably the most comprehensive in what it will do and higher power than the others so worth looking at this too. After that, the particular variant depends on what other controls you may want eg on/off channels for lights, and which transmitter system you want to use. The TX20 and TX21 will only control one loco at a time, all the others must be switched off. The TX22 will control up to 12 locos with control switched from one to another by the transmitter knob. So if you might want to control the three 33's then the TX22 would be the one to go for. You then need a "Selecta" enabled receiver to work with this, ie the "22" variant. The receivers come set up for a particular transmitter and with standard outputs for lights etc. set up as well. If you explain to Micron what you want they will come ready set up and so you do not need to program them yourself. If you want to change the program you can do so, this includes settings for individual outputs as well as the variant eg from "1" to "2" to "22" etc. To do this you need either a standard Spectrum aircraft two stick transmitter or one of the DelTang PROG devices (eg PROG3). The TX72 also gives some programming capability, but this is still being developed and it is currently restricted as to what it can do, so may not be the best solution for you. The DelTang website lists the different receivers etc here http://www.deltang.co.uk/index.htm And what the RX65 receiver can be programmed to do is listed here, for example http://www.deltang.co.uk/rx65b-v611-p.htm There is a corresponding page for each receiver. Hope this helps Frank

If you have to extend the motor shaft, you can do this with a piece of brass tube with a suitable internal diameter - if of course you can find a suitable size. You can use it to step from one size shaft to another as well. Or you can just use it as a short collar to connect the motor shaft to an extension piece the same diameter. Not all brass tube is the same, though, some makes are straighter than others - although this may not matter too much if using as a collar or if the extension is not very long. You can fix it on with Loctite or similar - I use the non-permanent variety which works fine but can be removed if necessary. Frank

Nice! Frank

If there really isn't any connection to the pad on the LHS then it could just be to mount the "external inductance" on? Frank

Hi Robin Glad to hear you got it sorted. 0.1 microfarad sounds a bit high for suppression capacitors. They are usually 1-10 nF. 0.1 microfarad is 100ohm at 16kHz, the sort of PWM frequency suggested for coreless motors. This is a bit on the low side and could affect the performance. The usual advice is to remove the suppression caps when fitting radio control. Frank

If you really really want good slow running, you can fit radio control to a kit built loco on a Kato 103/104 chassis for about £100 for the complete setup including the transmitter etc. and never have to nudge the loco, or clean the track, ever again! Frank