Hi, John,

Welcome to the forum (a few years late, but anyway).

Some 37xx locos do not have automatic system detection.
There should be a DIP switch with eight positions on the decoder (in the car with the motor). All switches off is analogue operation. The CS2 can show you how to set the switches for a specific address.
Make sure that not all eight switches are off. And only use combinations suggested by the CS2.
Switch 1 on is address 78, switches 1 and 3 on is address 72.

A picture will help if you think it was modified.

'03/92 MARKLIN' show on board mean March 1992 that one was from 2976 starter set analog or 3370 train pack analog I guess.

Photo of 3370 that same your.

Steven & Tom,

Thank you for your replies and the information.

The number on the bogie is: H506946B so it looks as if it is an 'Elisabeth' but with an analogue board. The mystery continues.

I have seen the correct board for this on Ebay but it is very expensive, more than the set is worth. I am undecided if it is worth the investment. Do either of ye know of a source for a board at a reasonable price?

John

I think ultimately the best solution is given in the fourth link Dave provides just above. That is afterall, what I did. These old first Gen MM decoders have minimal functionality and no motor control. I converted both the 3770 that is shown in that thread and a 3750 Elizabeth set. That said, I will send you the decoder from the 3770 set if you would like it. I will not sell it. I do not wish to suffer the greif of someone who damages it when they install it. The small sum of money just isn't worth it. My experience in selling digital equipment, especially old decoders, is that the installer is generally over their head and they just end up destroying it through simple mistakes or a static discharge. Marklin was quite clear back in the middle 80's that static matts, a wrist ground strap and a soldering iron with a grounded tip was essential. I purchased those items then and I still have them. Since it's removal, the decoder has been stored in an antistatic bag. Just PM me your address if you would like it.

The other thing that has been missed is the type of motor fitted.

If you look at Steventrain's photo, his motor has the white permanent magnet fitted, this is required for digital, but not Delta, operation.

Your photos only show the top of the motor, when looking from the side does it have the white permanent magnet or a coil of wires, indicating an analogue motor?

If an analogue ac coil, then the mystery deepens as to how an Hxxxxxxx serial number is on the chassis.

John, I noticed that as well but found this & realised they did come out like that from the factory but I am still trying to figure out how it operates

https://www.google.com.au/search...t315175%252F%3B640%3B480

I'm thinking the original decoder died and the owner probably didn't run digital so the e-unit from a 3370 was a simple, inexpensive way to fix the problem.

John, while you are at it do the small "flickering light" modification. Get the board & go form there. That is your best bet as Ashley so rightly pointed out. I will try to find that simple modification in English unless someone has it on tap?

Cheers

Dave...


PS: John this is the only one I can find to cure the flickering lights namely http://members.ozemail.com.au/~...tew/rms/pdf/tip_ice2.pdf. This one I mentioned before.Some where I have seen on one of the German forums a very simple modification that has to be done to the motor end of this loco to fix the issue & I remember it was all in German but I cannot for the life of me find it. Sorry about that. Maybe a German speaking Marklinist might be able to spot it in maybe Stummis forum?

Edited by user 30 April 2014 01:51:52(UTC)  | Reason: Not specified

Thank you to all for the advice. Things are moving in the right direction and hopefully I will have 3750 on the rails again without flickering lights.