highpeakman

I corresponded briefly with you the other day on another platform about decals for re-numbering the J94. You mentioned that you had ordered some on Ebay. I just wondered if you have received them yet and whether they look correct? I have ordered similar but am still waiting for delivery. You have really captured the feel of Derbyshire with your work above and it's helping to get me back to working on my layout and models which have been pretty much dormant over the last few months. Thanks. I have always been interested in any railways but the lines and the countryside of the Peak District always have been the main focus of that.

GPS satellites are not geostationary. The constellation of 24 satellites constantly move in orbit around the earth - all with different orbits so that there will always be a number in view at any time. There are also two types of signal transmitted, one of which is used by the military and one, slightly less accurate and more susceptible to jamming, for public use. As you would expect the military grade signal is not available for public use but it is the prime reason for the satellites being there. Accuracy of position is determined by triangulation based on measuring the time taken for the satellites signals to reach the receiver. Accuracy of position information will be determined by quality of software, and the equipment used plus getting a clear view for receiving the signals. In cities where large tall buildings (which both shield the signal but also reflect it causing errors), trees and tunnels occur there can be temporary loss of sight of satellites which a reduction in accuracy of position although not usually major. Usual accuracy should be, at worst case, 30 metres but is usually better. Sometimes maintenance (or fault) of satellites may reduce accuracy for short periods but, again, usually not major as with the constellation constantly moving new satellites come up over the horizon continuously. Usually the receiver has a capability of smoothing out some of these perturbations. The faster you are moving the greater the potential for losing positional information. Some of this can be seen when using a car sat nav in major cities. I have not had it happen in the UK but in Toronto centre I once got lost because the sat nav just lost all ideas of where it was in amongst the sky scrapers.

I would very much appreciate some guidance please to find some suitable transfers for my C&HP J94s. I am in the process of detailing my 3 J94s (so far). I have one DJM model 68012 and two Hornby ones, one of which is 68006. I will be doing a complete renumbering of the third one to 68013. (The Hornby ones have had the high bunkers cut down and the buffers corrected since the picture was taken and before anyone mentions it!) From study of photographs (and my own very distant memory) the size of the numbers on the tank side are correct on the DJM model but too small on the Hornby version so they need replacing. They appear notably bigger than standard BR number sizes for cab sides so I wonder if someone can point me in the right direction to get suitable transfers of the correct size and colour? I have looked at Fox but they appear to say their J94 offering is cab side. I have just been informed of Railtec and will explore their product but haven't found any others yet. I have some HMRS transfers but the biggest ones on the sheet don't seem quite big enough for this application but I might be mistaken. Any suggestions or guidance would be welcome please. Thank you.

I have just got my encoder from RS and have successfully removed the old one from the board using braid to take most of the solder off and then laying the iron briefly along the line of pins while gently prising the old encoder from the top. Only took a couple of minutes. I then used a suction desoldering tool to clear the solder from the through holes afterwards. The Thumbwheel just pulled easily off the old encoder shaft although not a loose fit. I note that the shaft of the old encoder is not round and has a substantial filed flat edge on it which fits into a "D" hole in the thumbwheel. It means that a flat will have to be filed across the new encoder shaft for it to fit nicely. This doesn't seem to have been mentioned above so not sure if my Powercab is different or if it has not been mentioned/noticed.

I was going through lots of old catalogues and leaflets today (Why do we keep so much old stuff around?) and found this. I thought it might stir the memories of some perhaps. Was it better than the Zero 1? Anybody out there who has one in use?

A few miles from here there are (or were) bridge warning markers that are a few miles from the bridge they are warning of on an "A" road. A gantry stands over the road with some hanging markers dangling from it. Presumably high enough (bridge clearance height) so no risk to windscreens but low enough to "clatter" on the bodywork of an over height vehicle. I have no idea how effective that would be or is in practice. I suspect that the type of driver who "doesn't see" a warning sign probably wouldn't hear such a warning anyway. I don't know what the dangling bits are made of - presumably they have to be fairly hefty to make a significant noise but not too hefty in case they cause damage (it might be that the vehicle will not need to go as far as the bridge in this case). They used to use similar things in front of level crossings where the road went under OLE wires on level crossings and probably still do? I don't hear as much about "strikes" on OLE but they must cause as much disruption as bridge strikes plus a few more sparks!

We used to get some real "pea soupers" in the Nottingham area in the 60s. I can remember driving by following the white centre lines on the road and hoping that there was nothing actually in front! (Young and stupid!). I have driven tens of thousands of miles around the UK since then but not come across anything so bad since. I was told at school in those days that Nottingham was actually the foggiest area in the country (by a Met Office technical definition and based on the most foggy days rather than density). Not sure if that was correct or not.

Thanks. That would explain them. I look forward to hearing more about that part of the work in time.

What are those circular structures on either side of the box?

This one was slow and noisy before this, although bearable.

I have recently suffered problems with the PCB on one of these locos after I removed the decoder chip, returning it to DC operation, but eventually overcame that by replacing the 8 pin DCC socket and some careful reflowing of solder joints. (Covered in another thread in the DCC help area). Having done all of that I carefully lightly lubricated the bearings (oil) and gear train (grease) but now find the loco will only run for about 30-40 seconds on the rolling road before slowly grinding to a halt. This happens no matter which direction it runs or what speed it is set to. After about a minute it will run again before again slowing and stopping. Presumably over heating? This is one of the first generation Heljan Cl 17 and I know there were a lot of problems with the motors but it has always seemed to work fine on my layout. The only thing is that my layout is a relatively short out and back so it may not have demonstrated this fault until I tried continuous running on the rolling road. Can anyone advise if this behaviour is typical of the problems with motors on this model please?

Still having a problem with this one. I replaced the 8 pin decoder socket as I could see that one of the pin sockets was damaged. Unfortunately it is still not making good connection with supply volts and there seems to be some PCB track problems. If I was keeping the loco I would happily replace the PCB with hard wiring but, as I intend to sell it I would like to have it back to factory condition if possible. So, I would now like to replace the whole circuit board but it seems that Gaugemaster (the official Heljan spares stockist) does not have a stock of Class 17 spares. The site states that no breakdown diagram is available for this model so I can't get the precise part number of the PCB. A reply to my query about this advises me that you just have to plough through the list of part numbers until you find what you want but although the parts price list contains several cl 17 part numbers there are no pictures or description of what each of them is. Curiously all cl17 parts that I have found are listed at £1ea. Perhaps I may have given up too soon as the list contains all the parts for all 00 Heljan locos (at least 1,000) and are not listed in any particular order but seem to be randomly listed. I could not find a way to reduce this list to just cl17 parts. A further query to GM about this has not yet been answered. So, please, if anyone has a part number diagram of the class 17 or knows of an available pre owned (or new) PCB to suit perhaps you would be kind enough to advise. Thanks. Edit: Update: Further work on reflowing soldered joints on board appears to have solved the problem - at least for the moment!

As noted above, about 6 different blanking plugs of differing types! One decoder works but an identical one (tested good) doesn't! I'll get to the bottom of it but need a bit more time to work on it at the moment.

Thanks for the suggestion although I have tried that. I do have track voltage on the pins at the topside of the blanking plug but it is not reaching the motor tabs on the PCB. Curiously it is reaching the loco lights so it looks like a probable PCB fault. I have "reflowed" the solder pins on the PCB under the socket but no solution yet.

Thanks very much for that article and pics. Brings back many memories. I was there in that crowd somewhere as we did the show for many years. I moved to Derby in 1954 and the smell of the Works got ingrained into my blood especially when going into town over London Road bridge on the bus. I always insisted on being upstairs so I could get a good view of the shed and works. If I go now to visit a heritage railway the smell of hot oil and steam takes me straight back to Derby Works.

Thanks Nigel. I have just removed the PCB and am about to start examining it. I will reflow the joints around the socket. I think that what was getting to me is that if it is a bad joint/broken track then I would expect to see some sort of connection problems with the working decoder plugged in as well. But touching around it and the board has no intermittent effect on it, it's rock solid. I have now plugged that decoder in around a dozen times - always the same - works perfectly immediately. However I have just plugged in another decoder of exactly the same type (with the same type of plug and which was verified working using the ESU tester) and that doesn't work either (lights work but not motor)! Looking at the PCB I have found one point where a couple of resistors are placed on the board and the joints don't look good but also they are covered in insulating tape to stop them shorting on the chassis but they have broken through the tape. Don't think that's the fault but it needs looking at nevertheless and may mean other things are quite right. This model is first generation of this model and I think there were other problems with the model and Heljan offered replacement chassis? This one wasn't refitted. I have to do other things now but will get back to it later. Thank you for your suggestions.

There's interesting! Haven't had time to take the PCB out yet but if I leave the decoder plugged in but put DC on the track it works perfectly happily! (Obviously the decoder is set to allow DC running). Can it still be a pin/connection problem? The decoder plug makes thing work correctly but any normal blanking plug doesn't work unless pressed hard in one direction. Driving me mad!

I tried bending the pins slightly on one blanking plug and that made no difference. If I "twist" the plug in the socket - and not lightly - it does connect and the motor works. So it looks like it may be a bad connection on the socket into the PCB. It still bothers me though that the decoder chip plug just fits in and everything works as the same connections must be used. Need to remove the PCB I think.

You may well be correct. I just noted that if I push carefully sideways on the blanking plate then it will make contact and the loco runs. That could be an intermittent contact on the base of the decoder socket or, as you rightly point out, I had wondered already as the pins on the decoder look to be a bit bigger than those on the blanking plugs and that would make sense as to why it works but the plugs don't. I was a bit puzzled as I would have thought that at least one of my 6 blanking plugs that have been tried would still have worked. I was just about to make a "jig" out of another old decoder plug but will try bending pins on one of the plugs to see if that works first. Thanks.

That looks like one of the blanking plates I have and have tried. I am currently suspicious of the socket on the PCB - either making contact with pins in a plug or a soldered connection underneath the socket. Thanks for taking an interest.

Thanks Nigel. I didn't originally see any signs of an intermittent contact and, because the decoder worked OK, hadn't looked to closely. After a lot of finger poking there does seem to be something suspect around the decoder socket or the "bedding" of plug contacts into the socket although precisely where I am unsure at the moment. I think it has to be something like that. Looks like I will have to remove the PCB and check, which I was reluctant to do, but now seems necessary. Thanks for your help.

Thank you very much for the suggestion. I had wondered about using the test rig like that and will now try it although, as I have used several blanking plugs, I don't really suspect them. I asked about the plug in the picture as I was going to try to put the original one back in the loco but can't remember which one was there when I took it out!

Thanks for your answer. I have already tried a lot of that. I have used several different plugs with no difference in result. Also it always works first time with the decoder fitted no no dodgy connections have been seen - so far. Believe it or not I do have an electronics background although my practical training was left behind in the 60s and 70s. However I also remember that sometimes the b....... obvious can be overlooked by the best and that description doesn't apply to me! Thanks again.

Thanks for pointing that out. You are, of course, absolutely correct and I have actually been working on that basis. Looking at it again I can't work out why I typed those pin numbers but I wrote it after a very frustrating day (disconnected reasons as well) trying to sort this out and, being tired, didn't read it back which I normally do. My lack of ability to type correctly really isn't the same as my testing ability however and I have actually checked the correct pins. Summing up. I refitted the decoder and it works correctly on DCC. Blanking plug(s) fitted it will not work on DC. Removing both the plug and decoder and measuring on the decoder socket pins: Measuring voltage across pins 4 (black) and 8 (red) I see full track voltage. I also applied dc power directly across pin 5 (grey) and pin 1 (orange) and the motor does turn normally. I have tried several different blanking plugs - even one which only links between pins 4 to 5 and pins 1 to 8 (so not inc 6&2) - loco will not work. I am aware that orientation of the blanking plug does not affect it. Pic shows test track with voltage and one of the blanking plugs used connecting the pins as above. Can anyone confirm that the pic of a blanking plug is the original Heljan one please?

I'm still being puzzled by this one. There is full track voltage (dc) on the blanking plug pins 8 (red) and 4 (black) which are linked (on the blanking plug) to pins 1 & 5 (orange and grey) which should be the motor drive. As the motor functions with a decoder in place there does not appear to be a problem with it. Now about to make an 8 pin header with connections so I can apply volts directly to pins 1&5 without the other pins in place and trace the connections to the motor but, before I do that, again, has anyone out there got any ideas please? Something on the Heljan PCB perhaps causing an issue?