Welcome to the forum   
Welcome Guest! To enable all features please Login or Register.

Notification

Icon
Error

Share
Options
View
Go to last post in this topic Go to first unread post in this topic
Offline johnmarklin  
#1 Posted : 05 February 2019 21:43:35(UTC)
johnmarklin

Ireland   
Joined: 31/03/2011(UTC)
Posts: 171
Location: Ireland
Good evening fellow Marklin enthusiasts.

I just received a little used Marklin 37990 today. All is complete and in very good little used condition except for the owner's documentation which is missing but that is not a problem.

I am running the Big Boy using a CS2. When the loco runs with chuffing sound turned on the sound can be perfectly synchronised and then all of a sudden the chuffing speeds up even though the speed of the loco remains constant. The chuffing can equally slow down even though the speed has not been altered. Has anyone experienced this weird behaviour with this loco or does anyone have any ideas or suggestions? Could it be the sensor needs cleaning or adjusting? I assume that there is no factory re-set option on this type of decoders.

Thank you in anticipation of your comments.

John
Offline AntoinePrt  
#2 Posted : 06 February 2019 07:00:21(UTC)
AntoinePrt

France   
Joined: 06/01/2017(UTC)
Posts: 143
Location: Ile-de-France, Paris
Hello John,

Maybe you can have a look here.
https://www.marklin-user...rect-sound-with-CS-60215

I have the 37996 so I cannot help you on this.

Sorry.

Keep us posted.

Antoine
Offline klarinettmeister  
#3 Posted : 06 February 2019 17:00:58(UTC)
klarinettmeister

Sweden   
Joined: 13/02/2008(UTC)
Posts: 798
Location: Kirseberg
Hi!
That's very strange. My 37990 didn't act like that at all on the CS2. There could be something that's been changed. There are 2 potentiometers inside the tender casing. I don't remember exactly what they do.

Offline dickinsonj  
#4 Posted : 07 February 2019 02:07:31(UTC)
dickinsonj

United States   
Joined: 05/12/2008(UTC)
Posts: 1,676
Location: Crozet, Virginia
Originally Posted by: AntoinePrt Go to Quoted Post


You can learn a lot about this problem from that thread - good suggestion Antoine.

Early in that thread I had some misconceptions about what was going on with my 37990. I was blaming my CS2, since I had not seen that sound problem when I ran it with my old 6020 controller. Luckily people with more knowledge of Märklin's digital system were able to help me eliminate some of my wildest theories. BigGrin

Pay attention to my posts starting with #15 and you can see what I eventually learned and how I overcame that problem. I have run that loco for almost two years since that thread was active and the sound remains perfect as long as it is on clean track with a proper power bus. Cool
Regards,
Jim

I have almost all Märklin and mostly HO, although I do have a small number of Z gauge trains!
So many trains and so little time.
thanks 4 users liked this useful post by dickinsonj
Offline johnmarklin  
#5 Posted : 07 February 2019 13:58:09(UTC)
johnmarklin

Ireland   
Joined: 31/03/2011(UTC)
Posts: 171
Location: Ireland
Thank you all for your comments links and observations.

I think that I am on the way to solving the problem. What is unusual is that the loco sound goes out of sync. at a point close to where the power is fed to the layout but it works perfectly well at the furthest point from a track power connection. I observed the loco for a while and noticed the problem occurring at a point where two track pieces are joined. Using my multi meter I checked the rails for continuity and no issue was identified but when I checked the centre rail I detected a raised level of resistance between one rail and the next. This was unexpected as the rail is new in a dry environment and all contacts are in place. My next job will be to replace the section/sections of track and hopefully that will solve the problem. I had a Big Boy from a mega starter set before and ran it on the same layout with my CS2 with no issues.

Will keep you posted.

John
Offline dickinsonj  
#6 Posted : 07 February 2019 15:20:35(UTC)
dickinsonj

United States   
Joined: 05/12/2008(UTC)
Posts: 1,676
Location: Crozet, Virginia
Originally Posted by: johnmarklin Go to Quoted Post
Thank you all for your comments links and observations.
...
Will keep you posted.

John


Thanks for the update John.

I think that this problem is mostly limited to that first edition of Big Boys and I have wondered if it was related to the signal generator which synchronizes the chuffing sounds. My only other loco with similar sound problems is one of the double set crocs, which stops and restarts its sound when it encounters a diminished power supply. My power bus has fixed that one though and it is certainly not as sensitive as the 37990 is.

What would solve the problem permanently would be to upgrade the primitive electronics in that loco but it is more complex than most locos and I hesitate to upgrade that one myself. Other than the sound issues it runs as beautifully as it did 18 years ago and pulls the longest consist that I can muster. On the plus side it does at least provide a circuit tester for my track. If the 37990 maintains sound sync then I know I have nailed my track integrity. Cool

It sounds like you have found a major part of the problem by identifying that resistance in the center rail. I had not thought of that and I will check for that if/when I see that problem again. For whatever reason that loco is extremely sensitive to any interruptions in the quality of the power supply. I find it particularly worrisome that new and expensive Märklin track does not have electrical integrity right out of the box. I assume that you are running C track although you did not say.

That reminds me of my 24712 turnouts, some of which have never worked properly from new. Not being able to count on basic layout elements like track and turnouts is really making me question my loyalty to my favorite brand of MRR equipment.

I look forward to your updates and hope to learn more specifics of this problem as you progress.
Regards,
Jim

I have almost all Märklin and mostly HO, although I do have a small number of Z gauge trains!
So many trains and so little time.
thanks 2 users liked this useful post by dickinsonj
Offline kiwiAlan  
#7 Posted : 07 February 2019 17:13:09(UTC)
kiwiAlan

United Kingdom   
Joined: 23/07/2014(UTC)
Posts: 8,082
Location: ENGLAND, Didcot
Originally Posted by: dickinsonj Go to Quoted Post

I think that this problem is mostly limited to that first edition of Big Boys and I have wondered if it was related to the signal generator which synchronizes the chuffing sounds. My only other loco with similar sound problems is one of the double set crocs, which stops and restarts its sound when it encounters a diminished power supply. My power bus has fixed that one though and it is certainly not as sensitive as the 37990 is.


If I remember correctly the 37990 is the Insider Big Boy and has two decoders in it to get the required number of functions (8 or 9), and these are set to consecutive addresses. The decoder driving the motor is a 6090 series, which is why it has the potentiometers for max speed and acceleration.

I believe all the later Big Boys had mfx series decoders, but I could be wrong on that.

Offline bph  
#8 Posted : 07 February 2019 17:18:48(UTC)
bph

Norway   
Joined: 04/08/2018(UTC)
Posts: 985
Originally Posted by: dickinsonj Go to Quoted Post
Originally Posted by: AntoinePrt Go to Quoted Post


You can learn a lot about this problem from that thread - good suggestion Antoine.

Early in that thread I had some misconceptions about what was going on with my 37990. I was blaming my CS2, since I had not seen that sound problem when I ran it with my old 6020 controller. Luckily people with more knowledge of Märklin's digital system were able to help me eliminate some of my wildest theories. BigGrin

Pay attention to my posts starting with #15 and you can see what I eventually learned and how I overcame that problem. I have run that loco for almost two years since that thread was active and the sound remains perfect as long as it is on clean track with a proper power bus. Cool



Thanks Jons for your posts regarding this issue.

I have the 37990 myself and working on upgrading from 6021 to a cs3. It works fine on 6021

Has anyone tried to use capacitors on the decoder, custom ore something similar to 60974 ?

Offline dickinsonj  
#9 Posted : 08 February 2019 01:07:59(UTC)
dickinsonj

United States   
Joined: 05/12/2008(UTC)
Posts: 1,676
Location: Crozet, Virginia
Originally Posted by: kiwiAlan Go to Quoted Post

If I remember correctly the 37990 is the Insider Big Boy and has two decoders in it to get the required number of functions (8 or 9), and these are set to consecutive addresses. The decoder driving the motor is a 6090 series, which is why it has the potentiometers for max speed and acceleration.

I believe all the later Big Boys had mfx series decoders, but I could be wrong on that.



That is exactly right on the 37990. It has zero mechanical issues and the motor is a beautiful beast. BigGrin

It uses the two consecutive addresses as you say to make it incredibly fully featured for the day. There was no more room on that ancient chip so they set the speed and acceleration with those pots. Of course today that looks a bit kludgy but they worked with what they had. I hope that later editions had better decoders but I was totally out of the Märklin market during all the time that they made the later Big Boys. So I have a lot to learn about those locos and the tech inside. If I remember correctly someone on this forum said that the quality of the motors was degraded at some point but I don't remember when. It and my Württemberg C have such lovely motors that they ran perfectly long before modern decoders were even available.

I might consider a later edition to accompany mine sometime in the future. I also thought about sending it to Helmut and having it redone correctly because it is so perfect in every other way. I imagine that decreases any collector value it might have, but I doubt if there is much there anyway considering all of the later editions. That is not my main goal with my trains anyway - I want them to work well and be able to enjoy them and probably won't ever sell them.

My wife wants a spreadsheet - good to see that she is planning (I hope a long way) ahead. ThumpUp
Regards,
Jim

I have almost all Märklin and mostly HO, although I do have a small number of Z gauge trains!
So many trains and so little time.
Offline dickinsonj  
#10 Posted : 08 February 2019 01:11:10(UTC)
dickinsonj

United States   
Joined: 05/12/2008(UTC)
Posts: 1,676
Location: Crozet, Virginia
Originally Posted by: bph Go to Quoted Post

Has anyone tried to use capacitors on the decoder, custom ore something similar to 60974 ?


I think that might be tough. Have you seen the electronics inside that loco? They look a good bit like a school electronics project and appear almost built up by hand. Maybe that makes it easier, not harder. I don't really know because I am not an electronics guy, but there are three boards and they look primitive as hell, although otherwise they work extremely well.

It is kind of like how the US sent people to the moon with less computing power than a couple of modern phones. ThumpUp
Regards,
Jim

I have almost all Märklin and mostly HO, although I do have a small number of Z gauge trains!
So many trains and so little time.
Offline johnmarklin  
#11 Posted : 09 February 2019 17:47:19(UTC)
johnmarklin

Ireland   
Joined: 31/03/2011(UTC)
Posts: 171
Location: Ireland
Thank you all for your suggestions.

The search for the ultimate solution continues. Despite the fact of the resistance issue I have also discovered that when I power up the smoke generators the sound problem is exacerbated. This suggests there may be a problem with the installation of the generators. The sound goes out of sync at points near to where the power is fed to the track and settles down to normal at about the furthest point from the power feed. The fact that the smoke generators are having this effect on the sound points to a significant current draw which in turn impacts on the decoder. I will continue to pursue a solution and will let you know if I ever find it.

John
Offline dickinsonj  
#12 Posted : 10 February 2019 01:17:35(UTC)
dickinsonj

United States   
Joined: 05/12/2008(UTC)
Posts: 1,676
Location: Crozet, Virginia
Originally Posted by: johnmarklin Go to Quoted Post
Thank you all for your suggestions.

The search for the ultimate solution continues. Despite the fact of the resistance issue I have also discovered that when I power up the smoke generators the sound problem is exacerbated. This suggests there may be a problem with the installation of the generators.


Interesting. Since I switched to a CS2 I have never run any smoke units - too integrated into the rest of the house. So I have never seen that behavior and it makes sense that it might impact the chip output.
Originally Posted by: johnmarklin Go to Quoted Post
The sound goes out of sync at points near to where the power is fed to the track and settles down to normal at about the furthest point from the power feed. The fact that the smoke generators are having this effect on the sound points to a significant current draw which in turn impacts on the decoder.

Ok - so why is the problem worse near the power feed and better with more resistance causing track joints when you get farther away? Actually I had one mainline where I did get a very short screw up in my sound and it was the segment closest to the booster. That sounds like it is too much power and not too little though, right? But that does not make sense, at least not to me.

Originally Posted by: johnmarklin Go to Quoted Post
I will continue to pursue a solution and will let you know if I ever find it.

John


I would love to learn more about exactly what is going on with that loco because it is still at the top of my favorites list. I look forward to hearing anything more that you discover. Cool

Until I upgraded my electrical bus I often just ran it without sound or not at all. Have you looked under the front engine cover, where the signal generator is located? I oil pretty lightly and have found that pulse generator assembly awash in oil on mine. On my last layout, cleaning that whole assembly made the sound problem largely go away.

I assume that it is an early digital design flaw and that only modern electronics will really fix it to our current expectations. For now mine is fine and when it isn't I will have to decide what to do. It is quite frustrating to avoid the operating sounds on such a magnificent loco - If my problem returns I will probably consider a total upgrade after all.
Regards,
Jim

I have almost all Märklin and mostly HO, although I do have a small number of Z gauge trains!
So many trains and so little time.
Offline johnmarklin  
#13 Posted : 17 February 2019 12:14:02(UTC)
johnmarklin

Ireland   
Joined: 31/03/2011(UTC)
Posts: 171
Location: Ireland
The search for a solution continues. Regarding the resistance at the joint between two c rail track pieces I have identified the actual problem. The tops of the centre rail on one piece of track for about 25cm from the joint appear to have oxidized or a previous owner spilt some goo on the track. A quick rub of a track cleaning rubber solved the problem, no more sound drop out. It is more probable that something had been spilt on it as my layout is in a constantly heated room. The sound of the loco still goes out of sync in other areas of the layout and this is still more pronounced when the smoke generator is running. I am using the recommended power supply unit.

Can anyone tell me what is the purpose of switches 9 an 10 on the second decoder dip switch block. There is no explanation in the owner's manual other than 'Operating noise clock speed'.

looking forward to your replies.

John

Users browsing this topic
Similar Topics
Marklin 37990 Big Boy - Incorrect sound with CS 60215 (Digital)
by AshleyH 15/02/2016 11:33:54(UTC)
Marklin 37990 Spare Parts (Collector's Corner general)
by Fergs 21/07/2014 11:41:44(UTC)
marklin 37990 (General MRR)
by interno6 01/12/2009 17:18:43(UTC)
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.

| Powered by YAF.NET | YAF.NET © 2003-2024, Yet Another Forum.NET
This page was generated in 0.735 seconds.