murphaph

Thx Noel, Yeah I have built a couple of kits from openDCC (kind of the German MERG), DCC central station, booster, an occupancy detector based on current and some homemade feeback boards and sensors (s88 bus) over the years. I've recently put together a test oval so I can get familiar with RocRail as the control software using current sensing to detect when the train enters the block and photosensors between the rails to detect when the loco is at the stop point. Even on my little test oval with passing loop it's fascinating to watch the computer randomly route a pair of locos around. I can say I've learned a bit, though none of the hardware will not be used in my "big layout". I have already settled on hardware implementing the BiDiB protocol, which has good support here in Germany. Kits are available which pushes the cost down when you need a lot of inputs.

It has been an extraordinary year for us all so I doubt anyone is going to judge you guys too harshly for a delay. As others have said, far better to deliver a top class product later than a substandard, or perhaps "not up to IRM's usual standards" is better, model now.

Problem: Rear red marker lights on the 201 are permanently illuminated with the front marker lights unless the manual switch under the loco is operated. This kind of defeats the purpose of DCC etc. It would be nice to be able to remotely disable the red marker lights, while leaving the front white ones on. It looks unprototypical in some circumstances to have the marker lights on. (my) Solution: desolder the wires leading to the current switch and slot in a relay instead of the switch and trigger the relay using one of the remaining free aux outputs on your decoder (in my case I used aux 5), if you have any. Hint: a Lokpilot v4 that many units will have fitted does not have any spare aux outputs to do this. I have fitted a Lokpilot/Loksound v5 for this, but any standards compliant decoder with an aux 5 output should do. (kind of ) tricky bit: The NMRA spec calls for the aux 5 and above outputs on the 21MTC connector fitted decoders to output at TTL (transistor-transistor logic level, a kind of low power used for microelectronics and not strong enough to switch anything) so we need to take this TTL voltage and amplify it using a small signal transistor such as a BC107 or (as I used) a BC549. The amplified signal is then used to drive the coil of a sub miniature relay (I chose the omron G5V 12V, but any 12V relay that fits should be ok) where the normally closed output of the relay is connected to the rear marker lights + terminal on the 201 PCB, while the common of the relay is connected to the decoder + (again, K1 on the 201 PCB). The Aux 5 terminal on the 201's PCB does not go anywhere so you have to solder your wire directly to the pad of the 21MTC connector (please don't start soldering stuff to the decoder even if it appears easier, we want to modify the loco itself, so decoders can still be changed in and out without de-soldering stuff) Other bits: You need to fit a resistor between the aux 5 output on the 201 PCB and the base of the transistor (marked b in circuit diagram attached). The transistor collector connects to the other side of the relay coil and the emitter of the transistor connects to the decoder - (minus). I used the RHS of the resistor marked R5 on the 201 PCB rather than solder to the MTC21 connector, though you can do that too of course, just be sure to use decoder minus and not track minus or something. After desoldering the wires to the switch I black tacked the relay on it's head beside the switch. I then superglued the BC549 also upside down to the side of the relay. This is then easy to solder everything to. A so called flyback or clamp diode should be fitted across the coils of the relay even though ESU never mentions this in their own documentation about fitting a relay. This is purely there to suppress any induced voltage spikes during switching but should not be omitted as some decoders will be damaged over time if no suppression is included here. Note the flyback diod has the negative end connected to the decoder +. This is not an error, it's how it works. If this is reversed it will provide no protection. This all sounds more complicated than it is probably. The circuit diagram should clear it up. I've included a couple of pics too. The colours of the wires in the diagram don't always match the actual colours I used I'm afraid. The white wire I used is coming from aux 5 on the 21MTC connector via a resistor that is difficult to see because it is enclosed in heat shrink where it's soldered to the base of the transistor. Don't forget to use heat shrink or otherwise adequately insulate your wiring, especially at the transistor if you choose to do it my way. YOu could use a small piece of veroboard but space is limited in the loco so Iike my way with almost everything stuck directly to the upside down relay. You then need to map some free function key to aux 5. Briefly the circuit works by using the transistor as a switch. When the base-emitter junction is saturated, the resistance between the collector and emitter falls to almost zero, allowing current to flow from the decoder + through the relay coil to decoder -, this switching the relay. When the relay is not energised, the red marker lights + has a path to the decoder + so its circuit is complete and the red lights will be on if the marker lights are on. When the relay is de-energised the path is interrupted (you can see nothing is connected to relay pin 10) and so the red lights cannot illuminate, just like with the manual switch, except it's controlled remotely now. I've left the old switch in there as I can use that to isolate a stay alive capacitor (during programming) later. Any questions, feel free to ask. Any suggested improvements are also welcome. I know a FET would probably be a better job instead of the NPN transistor but I had them in my bits box. No warranty, modify your loco at your own risk, incorrect wiring can fry your stuff etc.

I don't have the loco yet. What effect, if any, do those switches have?

The traction motors become generators (thus helping to slow the loco) and feed current either back to the ohle or a battery (then called regenerative braking) or burnt off as heat in a resistor grid in the roof, as is the case with most US diesel electrics.

The 121s didn't have dynamic brakes, right? I don't think anything Irish except the 201s had any form of dynamic brakes.

Yeah the first thing you notice is the sheer weight of the box!

I Just watched Ernie's fantastic flickr videos of shunting keg wagons in Claremorris with what appears to be the Ballina branch train. Was this an unusual occurrence?

Mine arrived today too and I was really pleased to see no prices on the outside No major surprises as I already have other P42 items but still lovely to open them up and see the fine detail and feel the weight of these wagons. Looking forward to many more years of IRM triumphs!

Thx. Bit new for me but lovely models.

Indeed but it's easier to just ask in advance before bidding on something. I was recently disappointed with an eBay purchase that was described used but as being in excellent condition. When I opened it up I saw that somebody had pinched the factory fitted speaker and for some reason had removed the main PCB and lost a retaining screw in the process. The detailing on the loco was also broken off in several places. The dark underside of the loco means the pictures are not particularly useful unless very high res, which invariably they are not. In my case it transpired that the seller had himself bought it second hand and sold it on. DJ that's exactly it. I have seen other sellers indicate that the item is used and then explain in the description that it was just opened to test etc. Returning items from Germany purchased via the mother is a logistics nightmare and quite costly. I may bid on items on Irish and UK eBay and have them delivered to the mother (either because the seller won't ship to Germany or the postage rate is horrendous), to be collected in one go on my next visit home. If a loco turns out to be used it will almost certainly be too late to return it by the time I inspect it unfortunately. Neither seller, nor eBay itself could reasonably be expected to believe that I hadn't just run it myself in the intervening weeks/months. So I prefer to clarify up front what I'm bidding on these days before placing a bid

Any idea of a suitable era for these tanktainers on Irish rails?

Thx. The description says new for all of them, which on eBay should mean, brand new, unopened in box. But the description for at least one of those locomotives says "running perfect". It should be listed as used if it's been opened and run, even if for a few minutes to test it. I've asked the seller to clarify if the locos have been run or not. Awaiting a response.

I already bought a weedspray for the tanks and container for use on 20' flats someday and to repurpose the flats I am considering the spoils too, but don't tell the missus!

Great stuff. Already looking forward to a re-run with the red oxide bogies! I honestly think if two or three packs with different running numbers had been produced they'd have sold out almost as quickly this time, at least if I am anything to go by (and I realise a sample size of one doesn't provide statistically significant results lol). I "restricted" myself to two packs because they are duplicates. If a rake of uniquely numbered ones had been available as a bundle I'd have ordered it. I'm not moaning by the way. Just giving a bit of feedback on my purchasing motivations Well done again lads.

Any date to the picture?

Was it a mistake by someone or were there complaints by the public?

Why was it controversial?

Everyone enjoys different aspects to a greater or lesser extent. Why do you ask?

I'll have to have a 121 in my hands before I can say if the switches can influence anything under DCC. Noel are you using a MM decoder?

What sort of part would you have in mind? I'm no expert to be honest. My electronic days in uni are long behind me! I happened to have all the parts except the spdt relay so just went with it.

Ah that's good to know about the 071. I've fitted a sub miniature relay to a 201 but I haven't had a chance to test it yet. It requires a couple of additional components, even when using a v5 decoder. The aux 5 output is used to energise the relay coil but as per the nmra spec for the mtc21 connection, aux 5 is at TTL power level which can't do that energising and the signal therefore needs a small transistor (capable of switching 150mA or so) and associated resistor to amplify this TTL to a usable level. I'm not entirely sure if it's required with the ESU decoders but I put in a clamp diode across the terminals of the relay coil to prevent induced voltage spikes damaging the decoder when the relay is de-energised suddenly. I'll stick up a basic schematic once I've tested it.

I would really like to be able to buy a bag of those.

I'm assuming that you can certainly use the mm decoder out of the box to control the headlights, marker lights (cab lights?) as with the 071 and 201 but it was noticed on those locos that the complementary marker lights are always on or off, meaning when one end's white lights are on, the other end's red lights are also on. This is not prototypical when the loco is actually hauling something. The red marker lights should typically be off when hauling a train, with the red marker lights being on the last coach/wagon instead. A hardware change is required in the 201 (not yet sure about the 071) to enable the white front marker lights to be on without the red rear marker lights. This appears not to be the case with the 121. The lights are independently wired so can be (but aren't from the factory it seems) mapped to allow independent control. Anything that a Lokprogrammer allows in this regard can be done by modifying CVs with a command station like the ecos but it's more difficult and fairly error prone compared to the LP way. If you don't care about the red marker lights being on when hauling a train then you don't need to do anything.

Good post. There will be plenty of time for a more in-depth discussion of mods or small improvements people may wish to embark upon (I may well replace the speakers for example for a double iPhone 6s job, for example). I'm looking forward to hearing the sound belt out of the open vents. Where is the factory speaker located within the body actually?