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Rob, I was thinking that a breadboard might be a good investment, along with a bag of various resistors (I have plenty of LEDs already ...). I note that you keep the red and white LEDs on separate circuits and can understand your reasons. However, I was 'hoping' to be able to get the front white and rear red LEDs to work automatically on F0 the same as many of the current RTR locos. I'm hopeful that with a breadboard, and a good look at the circuits inside a Bachmann Class 44 I have, I can duplicate the effect. Hopeful being the operative word! Ian

Andi, That sort of implies that my 'series' solution will not work as the white LED will be too bright. Is that correct? If so, what's the best way to wire up the white LED and 2x red LEDs to give reasonable brightness to all 3 LEDs? (sorry to be such a pain) Ian

Gents, Many thanks for the responses. I had a feeling that it was something to do with the voltages being different, but my Google searches didn't throw up anything about it. If I'm understanding correctly, I have 2 choices: Series connection: 1x red + 1x red + 1x white + 1x 1k5 resistor (to give a total load of ~12v) Parallel connections: 1x red + 1k5 1x red + 1k5 1x white + 10k resistor Is this correct? The bit I don't understand is that a white LED needs a higher voltage, meaning is has a higher internal resistance. So why does it need a larger resistor to work? Ian

Having solved my problem with 'dimming' LEDs I'm now struggling to understand why I cannot get the white / red loco lighting to work. What I'm trying to do is use F0 to control the lighting as follows: Blue/yellow circuit - 2x red rear lights + 1x front light Blue/white circuit - 2x red front lights + 1x rear light In other words, when the loco moves it lights the headcode box at the front, while lighting the red lights at the rear, And this is to work no matter which direction the loco is moving. My circuit layout is below: When I try this, only the (correct) red LEDs light up. So what have I got wrong? With a bit of swapping around of the wires I can get the following to light on a single (white or yellow circuit): 2x red 4x red 2x white But I can't get 2x red + 1x white! In all above cases, the LEDs are in parallel. Is there a 'difference' between red & white LEDs that I'm not taking into consideration? Ian

It would be nice to vary the voltages, but the DCC chip I have only outputs 'on' or 'off'. I wish I could to solve another problem I'm having. Ian

After all my problems with the 'dimming' LEDs I decided to scrap the veroboard I had made and start again. A nagging suspicion was that the board was 'leaking' across the tracks, despite my best efforts to clean the tracks (with alcohol) and make sure the solder did not bridge anything it shouldn't. So, I took the opportunity to re-design the veroboard layout as follows: Assembly was much faster this time as I had all the components to hand and cut to size! I was very careful to clean the tracks at each stage and this time it worked. Hurrah. I checked the voltages on the blue/yellow and blue/white combinations and found ~13v 'on' and ~1.5v 'off'. The ~1.5v hardly lights the LED (unless you use a magnifying glass to look). Hopefully, once it's all installed in the Mainline Class 45 the lights will look 'correct' and not like a place of ill repute, as someone else appeared to get (see post above). Obviously, it's very important to make sure the veroboard tracks are 'spotless' and clean them at each step of the work. Ian

Martyn, I found this photo in "BR Standard Diesels of the 1960s" also showing the 'pioneer' Class 29 in two-tone green but small yellow warning panels. Note that the 'catwalks' were in place in this 1963 photo. Do you think they were in the original class 22s and removed as part of the class 29 conversion (maybe after initial conversions)? Ian

Rob, Good to see you back on the Cameo ... How many cuts did it need to successfully cut through 20-thou styrene? I can't make that out from your posting. And what was the pressure setting? With my Cricut 5-cuts just about got through 20-thou but not enough for the shape to pop out like you describe. I'm curious to know if can 'copy' your settings over to the Cricut to completely cut through 20-thou. Ian

Mark, My 'acme' sketch is attached below. All my previous (successful) attempts at loco lighting were 'hard-wired' and looked a mess. This time I wanted to 'tidy things up' by using some veroboard. When built it looks like this (with apologies for the biscuit crumbs that crept onto the photo). And I'm using connectors at each end for the LEDs. As you can see there are 4x 1k5 resistors in place. All the 'tracks' are on the underside. Ian

I used to use some of the '12v integrated resistor' type packages (using 1k5 + 0603 SMD) that came from Layouts4U with success. No dimming issue. I am now using 'bare' 0805 SMDs that came from Direct Train Spares in Burnley. Both supplies were red LEDs. Soldering the SMDs is fiddly, but not a problem under a magnifying glass. And in fact, I'm using the resistor off the Layouts4U package on the Direct Train Spares LEDs. So, you'd expect them to act the same, but they didn't. Maybe the resistor value is just a tad to small? Yes, I know about blowing SMD LEDs ... I used a pair of AA batteries as a test supply first (err, 3V ...) and that blew the LED right away. It was bright though - briefly. Now I use a 3V button cell ... (less current) and no problems. I have 3x DCC chips from Hatton to use at present. One is clearly blown, distinguished by the small hole burnt through the insulating plastic shrink wrap. I therefore have 2 others to verify it's not the chip causing the problem. Ian

Many thanks for the responses chaps, they are much appreciated. Just seems odd that no one has reported this 'dimming' problem before. Maybe its just me being dim? (hope not ...). Anyway, I have sourced some diodes from the local Maplin (while they are still trading ...) and will try those in series with my 0805 SMDs to see if that cures the dimming problem. The other thing I need to 'investigate' is if there are difference 'flavours' (voltages) of 0603 & 0805 SMDs. I've got 3v SMDs (it says on the pack - and they do light brightly with a 3v button cell) and I'm wondering if there are 12v versions of the same out there. That might explain my problem if the DCC standard is for ~13v 'on' and ~3v 'off' on the blue / yellow / white wires. Ian

I did try the CV8 reset, but it appears to make no difference. And according to the Hattons CV listing, there is no CV to 'modify' the brightness (as I see some, more expensive, chips do). My problem is not with the tail & head light coming on at the same time, one is always lit while the other is 'dimmed'. Ian

Rob, I did take a look through Brians webpage (found from a Google search ...) and that's what convinced me to put 1k5 resistors on each leg of the White / Yellow instead of a single 1k5 on the Blue. Didn't seem to help though ... Ian

John, Sadly I only have Hattons 8-pin harness chips at present (I do have a Hornby one, but it's hard-wired into the insides of an Bachmann 00-gauge Class 08!). I did try a few Hattons chips and got the same problem. As noted previously, this problem did not happen with 0603 SMDs from Layouts4U (with in-series 1k5 resistors) on the same Hattons Chips. Ian

Huw, Thanks for the above. I think the idea of an additional diode in series with the SMDs is a good one. Maybe that will a; limit the voltage even more and b; cut the voltage off below its threshold. I'll have to find out what the forward limiting voltage of a typical 0805 SMD actually is below which it does not light. I already have each end of the loco as 2x red in parallel (on blue / white) and 1x white(on blue / yellow) with the 1k5 resistor in series on each of white & yellow (obviously the other end of the loco has the white / yellow reversed, but otherwise identical). So quite why this results in 'dimmed' and not 'off' LEDs is causing me the trouble. Once I've tried the additional diodes to have 'off' LEDs, I will then 'fiddle' with the resistor value until I get the correct brightness. Might take a while though ... The strange thing is that I had some 0603 SMDs with inline 1k5 from Layouts4U, and they didn't exhibit this problem (with the same DCC chip type). It was the cost (~£1 each) that took me to buy 0805 SMDs (~£1.50 for 5). Am I missing something? Ian

I may not have made myself clear (easily done ...). The LEDs are wired to the Blue(+ve) + Yellow(-ve) and Blue(+ve) + White(-ve) pairs. Not heard the 'trick' of using the Red in place of Blue. Is this a common idea? I did try the single 1500 ohm resistor on the Blue, but changed to having the same resistor on each of the Yellow & White wires at both ends of the Class 45 (ie: 4x resistors). At least I appear to have got that bit right. What would be a 'common' value for the resistor with SMD LEDs? If it's a multiple of 1500 then I can double / triple up the resistors. However, I still don't see why / how the chip is giving 'any' voltage when the circuit is meant to be 'off'. Ian

I'm retro fitting DCC and lights to an old Mainline Class 45, and am experiencing problems with the lights (F0 headlights). They work, but don't go 'off' properly. They are still lit dimly - and enough to be annoying. I'm using 3v 0805 SMDs with a 1500 ohm resister to avoid blowing the LEDs (done that already!). They are wired to the Blue / Yellow & Blue / White DCC cables to give directional working. The chip is a Hattons 8-pin harnessed version. I checked the voltage on the yellow & white circuits and get ~13v DC when 'on' and ~3v DC when 'off'. Is this normal, and how do you avoid the LEDs being dimly lit at the 'off' voltage? Any help appreciated! Ian

An NEM362 Kadee (#18, #19) might be 'easier', but it's still going to need a hole in the bufferbeam (unless there's a 'trick' I'm missing - hence the posting!). And you need the Craftsman kit, which I believe is getting hard to obtain. I got mine from the 'spares box' at a Chesterfield model shop last year. Fingers crossed, someone will respond with some ideas ... Ian

Has anyone experience of fitting Kadee couplers (whisker type #156 or #158 probably) to the Craftsman DK16 bufferbeam kit for an old 00-gauge Mainline Class 45. A photo of the replacement bufferbeam (to be attached, correctly, to the bogie and not the body!). As far as I can see it is going to need a 'slot' cut through the buffer to take the Kadee, with the width of the slot wide enough to push the 'whisker' end of the Kadee through the hole (and then installing the draft box 'behind' the bufferbeam). Any help / guidance / suggestions appreciated. Yes, I know updating / modifying an old Mainline Class 45 is 'not worth it', but I've had the model from new (~1982?) and it's been in storage for most of it's life since and it's a nice 'challenge'. Ian

Naysay away, I've no problem with that. There's always an element of truth in both sides of a discussion. I'm sure I could get my ageing Lima and Hornby motors to run 'smoothly', but I didn't think I would be able to get the slow running abilities of more current models. With the CD motors (10-pole?) installed, I can get a model moving on Step-1 with a DCC controller (28-steps). Ian

The 1974 RCTS Coaching Stock Book has the following TSO 37xx listed as Sc: SC3704/96/98/99/3800/01/04/07/17/18/26. The 1976 RCTS Coaching Stock Book had following TSO 37xx listed as Sc: SC3792/96/98/99/3800/01/04/07/17/18. By the time of the 1977 RCTS Coaching Stock Book they were down to: SC3801/07/13. In the 1980 RCTs Coaching Stock Book they were still: SC3801/07/13 And by the 1981 RCTS Coaching Stock Book they were down to: SC3801 only. In all cases, the Sc ones were 64-seats (not 48-seats). Ian

From my 30 odd years working on railways, the superelevation is always applied by raising the outside rail. The one exception I had was Singapore Metro North-East Line & Changi Lines (built concurrently) where the superelevation of the tunnel tracks was applied by rotating the whole trackform about the centroid of the vehicle (~1m above the plane of the rails). Causes all manner of headaches, and I believe this was not repeated. Ian

I chose to replace the motors in a number of my old (~1980s) Lima and Hornby locomotives. The new motors certainly provide a smoother operation, especially at low speed. If you want details, let me know although all my information came off a couple of YouTube videos. Ian

I used to use an M2 nut and bolt, but I've found it is much easier (& cheaper ...) to use a self-tapping screw as you are usually attaching to a plastic surface. I found that either an MF-ST30B (No.0x6.4mm pan head) in black or MF-ST55 (No.0x6.4mm countersunk) from modelfixings.com (just a happy customer) work very well. All they need is a 1mm pilot hole to screw into. I mark the location for the drilling using a bodger (errr, is that the proper term? It's a sharp metal point attached to a wooden handle) through the hole in the Kadee draft block when it's in the correct location. I posted a few photos at http://www.rmweb.co.uk/community/index.php?/topic/112980-signaller69s-projects-more-coaching-stock/page-11&do=findComment&comment=2999278 Ian

Clive, I like that idea. Nice one. I can 'adopt' it for use with my Cricut cutter. I found the Cricut will 'cut' the styrene 95% of the way through, and I was wondering how to get the cutout out if it was very small (large cutouts can be released with a fingernail). I think your judicious use of diagonals will solve my problem. Thanks. I'll have to give it a try ... Ian