decoder woes

Hi , I have just received the loco in the title and have a problem I need some advice with , I ran it for the half hour in each direction as is recommended and it impressed me very much so I then removed the cab and tried to fit a Zimo MN170N decoder but it would not fit in the available space the pins on this decoder are quite long so I shortened them as much as I dared and it then almost fitted but not quite , I decided to give it a DCC address and ran it without the cab and I was even more impressed as it crawls slower than the laziest Snail and it was equally good at higher speeds .I decided that to get the decoder into the cab I would need to lose the 6 pin socket and solder the wires direct to the pins but i'm puzzlled as to how to proceed as the are just 4 wires utilising 4 pins they seem to be in 2 pairs with each pair consisting of a Black and Red ,on the underside of the socket you can see 4 solder joints 2 of which are marked M+ and M- withe the other pair marked + and - the 2 centre pins appear to be unused and I guess that's because the Loco being steam has no functions am I correct in my assumptions that only 4 pins are used ? .

cluncker said

Hi , I have just received the loco in the title and have a problem I need some advice with , I ran it for the half hour in each direction as is recommended and it impressed me very much so I then removed the cab and tried to fit a Zimo MN170N decoder but it would not fit in the available space the pins on this decoder are quite long so I shortened them as much as I dared and it then almost fitted but not quite , I decided to give it a DCC address and ran it without the cab and I was even more impressed as it crawls slower than the laziest Snail and it was equally good at higher speeds .I decided that to get the decoder into the cab I would need to lose the 6 pin socket and solder the wires direct to the pins but i'm puzzlled as to how to proceed as the are just 4 wires utilising 4 pins they seem to be in 2 pairs with each pair consisting of a Black and Red ,on the underside of the socket you can see 4 solder joints 2 of which are marked M+ and M- withe the other pair marked + and - the 2 centre pins appear to be unused and I guess that's because the Loco being steam has no functions am I correct in my assumptions that only 4 pins are used ? .

From “EFE N Gauge J94 ”, 23rd September 2023, 5:23 PM

Yes, I think that only 4 pins are being used.  I have hard wired decoders into 00 and 0 gauge locos but not N.  Should be the same though, the convention is standard for DCC.

Here's a tutorial from DCC Concepts:

A-DCC-Advice-12-Decoder-Wiring-Colour-Codes-Connectors-and-More-2014.pdf (dccconcepts.com)

There are videos if you search yourself.

Again I have no idea what your installation looks like, always better to post a picture.  Others with N experience may have a better answer.

John

Hi John , thanks for replying , I will try and get a pic or 2 tomorrow but to see the tiny inscriptions on the socket will be a challenge I think but i'll do my best .

This is my very best attempt at  a pic of the underside of the decoder socket , you can see I hope the 4 connection points , using a multimeter in continuity mode all 4 connections have continuity on all 6 pins with the blanking plug in but with the blanking plug out M+ has continuity with pin 1 and M- shows it on pin 2 , the + connection has continuity on pin 4 and the - connection shows it on pin 3 , so correct me if i'm wrong  but I read it as if I label the wires to show their respective pin numbers and then solder each wire to it's corresponding pin I will hopefully be good to go ,?   please let me know what you think .

I'm thinking the connections labelled "M" are to the the motor.  So should be grey and orange wires.  If you get the polarity backwards, no worries, CV29 can fix that.

The +/- connections will be to track and should be black/red.  So use the multimeter to confirm continuity from the connection on the board to wheels that have pickups.

Should be all there is to it.  The really critical thing is to get the wires to the right place.  As I look at the picture I find it difficult to tell which wires are red or orange.  Same for black and grey.  If you are confused you will need to do more disassembly to gain access to the motor and trace the wires.  Don't put power on until you are sure.

John

BTW, just looking at YouChoos.  The MN170 is 12x8.6x2.3.  The MX615 is much smaller at 8.2x5.7x2.

YouChoos
 

Hi Brossard , for whatever reason EFE have seen fit to ignore convention and have used Red or Black wires throughout I agree that the "M" wires are most likely the motor wires so that leaves a Red and a Black wire to decipher , if you look at the 2 wires on the bottom right they are Red and Black with the Red being + and the black being - , looking across the board from Right to Left the 4 connections are roughly inline with pins 1,2,3,4 with pins 5 and 6 not being used and the pin numbers I mention correspond to the numbers on the blanking plug , i'm not home at the moment but in a couple of hours I will test continuity as you suggest from the wheels to the - and + do you know which side of the loco corresponds to - and + ?

First priority is to determine which are motor wires.  After that, by elimination you know the track wires, but I'd confirm with a meter anyway.  As I said polarity isn't an issue because there's a CV for that.

The tutorial provides advice on which pickup wire goes to the left and right.  Be sure to read the cautions.

John

Brossard I entirely missed your link to the MX615 and apologise for that , I think that to remove all chance of damaging a very good decoder I have decided to place an order for a MX615N with coastal DCC who are a good bit cheaper than youchoos neither coastal or youchoos have it in stock so i've placed an advance order and will wait for it to come into stock , the MN170N will fit many of my other locos and I have one that runs very well on DC but I cannot get it to run nicely with it's current ESU decoder so i'll try it in there , thanks for all your help it is much appreciated .

All but one of my locos have Zimo sound decoders and they are really excellent.  The exception is ESU Loksound (J39) and that runs superbly as well.  These are really fine brands so I have to wonder why your other loco isn't doing well.

John

The loco in question is a Bachman N gauge 4 MT tank ,i've tried a Lenz silver mini the ESU and a CT Elektronik and it still fails to perform as I need on DCC ,on DC it's fine but it just does'nt seem to like DCC I intend to sell it and emphasise that it does'nt like DCC , the J94 is intended to replace it and should do a better job than the 4MT as it ill be confined to sidings under traincontroller control .

cluncker said

The loco in question is a Bachman N gauge 4 MT tank ,i've tried a Lenz silver mini the ESU and a CT Elektronik and it still fails to perform as I need on DCC ,on DC it's fine but it just does'nt seem to like DCC I intend to sell it and emphasise that it does'nt like DCC , the J94 is intended to replace it and should do a better job than the 4MT as it ill be confined to sidings under traincontroller control .

From “Post #288,745”, 24th September 2023, 4:06 PM

Well, I have no experience with N locos so really can't offer much.  If you haven't already done so, you could try playing around with CVs to try to tune the performance.  Start voltage, acceleration, those sorts of things.  Have a look through the manual.  Check other forums because chances are if you have the issue, others do as well and a solution may present.

John

I've spent a great many hours adjusting CV's to no avail and to be honest i'll be happier with the J94 over the 4MT as it'll suit it's intended purpose and location much better I think , what I actually intend is moving a Jinty from the sidings to a small servicing workshop where the 4MT was intended to do very littlle other than visting an ash pit and a sanding tower and then returning to the workshop ,the Jinty will now not be used in the sidings ( mostly coal) and will be replaced by the J944 to work the sidings along with an 08 , the new scenario appeals to me more than the old one .

Your taste in locos matches mine, although mine are somewhat bigger.  Dapol's J94 is due out by the beginning of next year.  Lionheart's 3MT is also due at about the same time.

John

I've always had a soft spot for steam and the dirtier and grimier the better lol , my layout although based on the BR LM region in the summer of 63 is more a collection of hazy memories from that year when I was 10 , given my upbringing in a seaside town in Essex where both of the lines to london were being electrified back then I wonder where this longing for the BR LM comes from as the only experience I ever had as a child was visiting a distant Uncle who was employed on the West Coast mainline , I only met him once for a long weekend but his stories of the railways in his youth stirred something in me that I never lost .The 08 was included in my scheme because the LTS line ran right past my primary school playground and one day in 64 a brand new 08 went past I guess on it's way to the depot and terminus at shoeburyness and there's another memory that I never lost , a few days ago turned 70 and yes I still miss those Golden days . I had another thought about the 4MT and realised that with a now spare Zimo chip going begging I would try that in the 4MT and see if it likes that .

Snap! Again, well almost.  My layout is nominally set in 1962 but in the Eastern Region.  My 00 efforts had always been LMS in the mid 30s and I guess I felt like a change.  I chose 1962 because it was a time when the infrastructure was still place.  The old locos were still in service along with first gen. diesels and BR steam designs.  My grandad, I am told, was a driver for LMS but also remote and far too intimidating for me to question.  There's a photo of him and a mate on a motorbike with an LMS 2-6-4T in the background.  I do remember spending a lot of time next to the L&Y main line which wasn't too far from my house.  I can still remember steam locos, just.  The family flitted to Canada in 1967 so that was that.  So, now I'm trying, with a few others, to keep British Railways alive here.

John

So you're in Canada ? we went to Aussie in 65 but only lasted 2 years as my burn under a lightbulb Mum just could.nt bear the heat I never could figure her out but then again she could'nt figure me either but why does a sun shy person decide to go to Perth which in Aussie is almost as hot as it gets but one good thing was that they still had steam and it was a reminder of home standing on a railway footbridge being bathed in steam soot and smoke and loving it .In the late 70's I lived in Bristol for 18 months and worked with a great guy who had driven steam under BR he had an LP record with one recording being himself driving a steamer out of Bristol Temple Meads he walked me along the route of a Beeching closed inner city line and I recently learnt that they are trying to re open that line that should never have been closed , he invited me to his house to show me something that he reckoned i'd like and there in all it's glory was an exact live steam coal fired 1/4 scale replica of flying scotsman that had taken him 12 years to build what a wondrous thing that was ,I sometimes wonder where it is now as I never saw him again after I left Bristol .I long for the day when BR lives again as someday people will come to their senses and bring back the Nationalised railway that on privatisation was the most cost efficient railway in the world according to the OECD .I had an auntie in Canada an East end girl who drove fire engines and Ambulances in the Blitz and them emigrated at the end of the war I know little of her but Know that she was in B.C she visited here in the mid 70's and was supposed to stay for a month but went back after one week as she said that England and especially London had become so built up that she felt that everything was closing in on her ,god knows how she'd feel now as everything is 10 times worse .

Family lore has it that we were supposed to go to Oz but my sister came along and that put us over some sort of family size limit, so Canada it was.

I went to New Zealand on holiday once and I was very impressed.  Temperate climate and no pests.

I have travelled to the UK many times for work and really enjoyed the chance to explore Hobby Shops and Railway meccas, like York, Steamtown in Carnforth and Severn Valley.  I have to agree with your aunt though, UK has got too congested and very expensive, or at least that was my take when I was last there some 20 years ago.  I could never go back to live.  Now, of course most of the Hobby shops are gone, as they have here.  I don't mind because I can get my British stuff quite readily on line and delivery times are quite good.

I had an old friend who came over a few years before we did but never went back.  He was also a railway nut and used to tell me how, if he ever got some money, he'd go over to tour all the Hobby shops.  I think his picture of the UK was fixed at the time he left, the 1960s.  He would have had a shock I think, not least because Hobby shops were vanishing.  He's gone now sadly.

John

Everything has gone it started in my hometown while were in Aussie , when we came back after just 2 years there was a giant hole in the ground where a wonderful shopping arcade had once stood and whole roads were demolished including many of those where my pre aussie schoolfriends had lived and were replaced with a failed ring road that never became a ring and god awful tower blocks that by the early 70's had become modern slums and it's gone on and on with even the very few buildings that the council said it would protect being bought up by developers and then mysteriously catching fire and having to be demolished so all this towns history went up in a developers favourite smoke .It's the same countrywide , I saw an estimate recently that said that if the current rate of building on green field sites that existed in 1980 was to continue to the end of this century then half of all agricutural land in the uk will have been built on , i'm glad i'm now 70 because this countries insanity continues to break my heart .I've just realised that we are actually on model rail site so if we chat again in future i'll try not to burden you with my woes and talk about trains and steam and some Diesel but deinately no electric please  .Tomorrow i'll try that now spare zimo chip in the 4MT and let you know how it goes .

Back on thread: The wire that goes to Motor + is supposed to be orange. The M - is supposed to be grey. these are the ones that should be connected properly. The other two from the pick ups can actually go either way round but I stick to the red to right and black to left rule.. If the motor wires are reversed the motor rotation is also reversed.

I've used 6 pin Zimo decoders and have de soldered the pins and soldered the wires directly. You should have a Zimo sheet that came with the decoder that shows which pins to solder to. If not, you can go to the Zimo website and it will show you on there.

The MN170 is the replacement for the MX617.

Hi , thank you you've made things clearer in my mind now but i'll leave the chip alone and use it elsewhere as i've pre ordered an MX615 with coastal dcc .