MTFCA Forum

I have some MARX trains from the 1950s 60s. One of the engine tenders features Sound of Power, an old style circuit board that creates static. The power is picked up by a wheel that rubs on the center rail. The wheel has gaps in it to stop the electricity on an equally spaced interim.

SO shh shh shh shh shh shh shh shh

QUESTION IS, Who still dabbles in the hobby that could analyze and repair a shorted out or just dead circuit board? I think I have a couple that don't work.

One of the old car radio shops could probably repair it or build one.
An old transistor AM/FM shirt pocket radio would make a very similar noise.

tom_strickling wrote: ↑

Mon Dec 18, 2023 5:43 pm

I have some MARX trains from the 1950s 60s.... Who still dabbles in the hobby that could analyze and repair a shorted out or just dead circuit board?

Tom,

I don't often frequent this forum, so have only just come across your request. As you probably realise I'm a fair distance from you, but it may be possible to provide some advice to assist in fault-finding. To that end I have a couple of questions:

(1) Do you have a good photograph of these boards?
(2) What voltage does the system work on?

Luke.

I can't help but you have struck a nerve. Several friends had Marx, and they were wonderful back then. This has nothing to do with Marx but is from the same era. Thanks for reminding me of those wonderful times.
Rich

Watch this video - the problem may not be the circuit board itself but there may be a short due to compromised foam insulation and/or poor conductivity that can be remedied by cleaning and polishing the wheels, center drum and the rivets where the trucks are fastened to the frame, etc.

https://www.youtube.com/watch?v=i1Mr9b5T864

I tinker with old computers from the 1970's and 1980's and one common failure point for them are the capacitors. Certain styles/types of capacitors start leaking and basically fail to work at all. If capacitors are involved look for any leakage or bulging capacitors. Also be very careful in dealing with capacitors, they hold a charge for some period of time after power is turned off - you can get quite a shock from them if they aren't discharged.

Based on what you've described, it sounds like you might be dealing with some classic wear and tear on those circuit boards. Don't overlook ModelTGal's advice about the capacitors. They're often the first component to go in older electronics.

ModelTGal wrote: ↑

Mon Apr 01, 2024 12:17 pm

I tinker with old computers from the 1970's and 1980's and one common failure point for them are the capacitors. Certain styles/types of capacitors start leaking and basically fail to work at all. If capacitors are involved look for any leakage or bulging capacitors. Also be very careful in dealing with capacitors, they hold a charge for some period of time after power is turned off - you can get quite a shock from them if they aren't discharged.

But that ruins the surprise. .