Bachmann Message Board

Discussion Boards => HO => Topic started by: MarkM on February 08, 2007, 11:50:23 AM



Title: USRA Light 4-8-2 DCC Conversion
Post by: MarkM on February 08, 2007, 11:50:23 AM
I have a USRA Light 4-8-2 Item No. 81602 and installed an MRC 1650 4 function decoder.  I made no other modifications other than plugging in the 8 pin decoder (after removing the jumper).  I am using an MRC Prodigy advance DCC system.

1.  The headlight is dim, not as bright as when operating on straight DC.  What voltage lamp is factory installed?  Any thoughts on how to make it brighter?

2.  Any guidance on how to dissassemble the loco?  In particular, how to remove the boiler shell in order to access the light PCB?


Title: Re: USRA Light 4-8-2 DCC Conversion
Post by: Hoople on February 08, 2007, 11:53:02 AM
MRC decoders are junk. That's why the decoders warm. I beleive MRC decoders are surrounded by heat shrink tubing, and they fail after 1-2 months. Change to a digitrax or a NCE decoder. They work much better.


Title: Re: USRA Light 4-8-2 DCC Conversion
Post by: Tim on February 08, 2007, 12:04:32 PM
Mark

Snip both capacitors or completely remove them.

As for the headlight, did you connect both wires to the decoder,
blue & white, or is one side still connected to the frame?

Tim
Souderton, Pa


Title: Re: USRA Light 4-8-2 DCC Conversion
Post by: MarkM on February 08, 2007, 09:17:36 PM
Tim,
Thanks for the advise.  I did not touch any of the wires.  I simply removed the jumper from the PCB in the tender and plugged in the decoder, verifying the red wire on the decoder did in fact plug in to the red pin on the PCB.

Hoople,
Thanks for the decoder advise.  These MRC decoders have no shrink wrap.  We'll see how long they last.


Title: Re: USRA Light 4-8-2 DCC Conversion
Post by: SteamGene on February 10, 2007, 09:16:03 AM
I don't know if the MRC decoders are junk, but they do seem to have a higher failure rate than the industry standard.  I asked some of my club members to evaluate four locomotives, two with Tsunami and two with MRC Brilliant sound decoders.  They were in four locomotives, two C&O J-2s aand two H-5s ( heavy Mountain and light Mallet).  These were blind tests and the MRCs won.  In fact one of Tsunami just got replaced because IT went bad.
However, programming the MRC is not very easy, and I've had to send several back to MRC where they apparently are currently out of stock. 
Gene