MTH CA-1 Caboose buzzing

Wow,

I will have to check my SP CA 1, along with my IC CA 1.

I will let you know the results.

Thanks for the heads up,

Richard

Well Professor,

Same problem here with both of my new MTH C1 cabooses. .  We had to wait a year for these things to arrive.

The noise which is a buzz and a crackling sound becomes more pronounced when the caboose is rolling.  As you mentioned the buzzing and crackling sound as if it is coming from the trucks.  The lights do not seem to flicker.

I guess we have to contact MTH and make them fix the cars.

Richard

Thanks for the info Richard - now I know it's not just mine!

The noise goes away if I unplug the connector to the marker lamps.  I am wondering if it has something to do with the unusual design of the regulator board - I will post something in the electrical forum and see if the gurus have insight.

Thanks,

I have a MTH Erie War Bond and NYC Pacemaker CA 1 from a few years back, and I never noticed this problem. We paid too much for the new MTH CA 1 cabooses to have to disconnect the marker lights.

I hope we can find an easy fix for this problem. Hopefully someone form MTH will pick up on this and provide a solution, or a RA  number.

I am sure other folks on the forum purchased these cars and will let us know about their cabooses tomorrow.

Richard

See this thread.

The problem seems to be caused by too small of a capacitor (10 uF) on the input of the regulator board that powers the 6V marker lamps.

Some possible solutions:

1. Add more capacitance to the input - another 47 uF in parallel with the 10 uF eliminated the buzzing. However, this increases the load on the voltage regulator, and may cause it to run too hot. The increased capacitance may also interfere with DCS signal, although that should be solvable with an inductor.
2. Ditch the MTH voltage regulator, and install a switch-mode power supply module to power the lamps. This is what I did. 5V and adjustable switching modules are plentiful on eBay.

Professor,

 I ran both of my new MTH CA1 cabooses with a Lionel Legacy engine today and although the hum and crackling noise persisted in both cabooses, there was no affect on the performance of my legacy system. I was concerned that this electronic noise would affect my Legacy signal.

Have you ran your CA1 behind an engine yet?

Thanks,

Richard

Hi Richard - I didn't try it before I modified the caboose, but I doubt it would be a problem. I'm no expert on these things, but the buzzing is probably at 60 hZ with the AC signal, and I assume that has no effect on much higher-frequency signals.

New CA-1 here buzzes too, thought it was we just had a bad one. Do your marker lights get hot to the touch at 18V?

Yes, the marker lights on mine were quite hot.

I'm running the switching module at 5V; should keep the markers cooler.

Two questions:

1) Is there a switch under the caboose to turn ON-OFF the lighting circuit? Of so, does turning it OFF stop the buzzing?

2) Has anyone contacted MTH about this situation yet? If so, any "response"?

There is no on-off switch, but it's easy to disconnect the plug for the marker lights to eliminate the buzzing. Wouldn't be hard to wire a switch either.

The roof on mine melted at 18V. The over head bulbs get to hot. The damaged area is under the roof walkways on each end. I started installing a piece of foil above the bulbs hopeing this will help.

NCT,

Is this one of the new CA 1's?

I have not contacted MTH about this yet, but bottom line - they should repair or replace these cabooses.

If MTH knows that theses cabooses will have to run on 18 volts in the DCS or TMCC / Legacy world, then how on earth could the let a product into the market place that melts at 18 volts??

Richard

NCT, where did the roof melt?  Over the bulbs near each end?  Or the cupola, which is over the voltage regulator?

At 18V the voltage regulator is dissipating about 2W and is too hot to touch.  If that's melting the roof that's showing that the whole design is trash.

Replacing the linear regulator with a switching module would prevent that.  A more involved conversion would be to change the 6V marker lamps to something else.

I have my receipt in hand now from the dealer I purchased the cars from. Of course the dealer is not at fault here, but MTH should step up to the plate here.

I wish I had the professor's electrons skills. I don't so I will end up having to deal with MTH on this.

Richard

I too have this caboose in UP livery. Purchased it last year. It also suffers from the buzz mentioned. I've never checked to see if the lights or markers got hot during command operation. We don't have a layout set-up at this time, but I checked last night and didn't see any evidence of warping or melting anywhere from previous sessions.