New Spectrum series 2 8 0 won't work on MRC Transformer

[JoeX]

WE just purchased a new 2-8-0 with Tsunami sound and the capibility to run on DC and DCC. WE tested it in the hobby store, it worked find on DC. Got it home and it was a no go on our track. We are running an MRC dual Cab Transformer with pulse and full speed switches. The loco just sits still with headlight blinking. After swapping to another transformer (single wired direct to cab 1) the loco worked and functioned as it should. What could be the problem? IS the pulse feature on this power pack a problem? Or is it the dual cabs? Or could this older transformer be putting out unclean DC that is causing the onboard electronics problems? All other DC locomotives we have work fine with the transformer.

[richg]

Turn off the pulse power. You are not suppose to use pulse power. I think that is in the documentation for the Tsunami on board decoder. The decoder expects DCC or DC, not DC with pulses.
Rich

[JoeX]

Rich, I know not to use the pulse power. I was just stating that the power pack has it in case someone is aware of circuitry used that might cause interference. The trial of the locomotive was made using the full power switch setting on the power pack. It would not run the DCC loco, the power pack does run all our other locomotives. This is an older power pack. Even though it works fine for the other loco's one thing I am wondering is if the filtering section for the DC is weak and "dirty" DC is coming out, would this compromise the new Loco's operation? This is the only thing I can think of? And this is IF these old transformers have any filtering.

[Doneldon]

Joe-

Many power packs with pulse power have a switch to turn the pulse on and off.
If you don't have such a switch you'll need to operate your Connie with a
different power pack. Pulse power is a problem for many DCC decoders. I don't
know if that's true in every case but I do know that it's often true.

                                                                          -- D

[jonathan]

Joe,

Thanks for asking.  This is interesting info.

My sound Connie runs okay on my MRC pack.  The pack does not have pulse power.

However, the loco runs better on my Spectrum power pack (out of production).  By "better" I mean the loco sounds off on a lower voltage with the Spectrum pack.  Also the chuff is faster, more in sync with the drivers.

Strange, but true...

Regards,

Jonathan

[Doneldon]

Jonathan-

You can't compare voltages by comparing throttle positions on different power packs. Only a meter will do that. If you read voltages with a meter, my comment is out of order.
                                                                                           -- D

[Johnson Bar Jeff]

Or could this older transformer be putting out unclean DC that is causing the onboard electronics problems? All other DC locomotives we have work fine with the transformer.

Joe,

I don't have the technical knowledge of some of the other guys on this board. But I can share my personal experience. About three years ago or so, I finally ditched a couple of old--I mean really old--MRC power packs, including a dual cab model with pulse power, that had been around since the early 1960s. I replaced them with a couple of brand-new MRC packs. I was honestly shocked at how much better even really old DC locomotives ran on the new packs. My Spectrum Richmond 4-4-0 runs just fine on the new MRC pack.

FWIW. ...

Jeff