MRC Sound Decoders

[snjroy]

Yeah, I have several MRC decoders, and my Digitrax system has a tough time reading CVs. I keep all my instructions, write the loco identifier on each, and write the CVs down for future reference. I do that for all of my decoders (contrary to Dave, I have pretty much every make on my pike... that's what happens when you buy things on sale!). And when they don't come with instructions , I download and print them. 

Simon

[fmilhaupt]

How old are these decoders?

If I remember correctly, the older MRC decoders were fussy about which programming mode you used. I don't recall off-hand which modes worked and which didn't, though.

[wjstix]

hobo9941

I still have a few MRC decoders that I haven't replaced. They are good runners, but I cannot lower the sound volumes, even when changing the CVs. Is there any way to lower the sound on these decoders.

 

Just to back up a second - so this isn't one MRC decoder but several? And none respond to a CV change of any CV? Sounds like a problem with your system rather than the decoders. Which model decoders do you have? CV settings have changed for MRC over time. Do you have Decoder Pro (or know someone who does?) That could solve the problem. As I mentioned earlier, I find MRC decoders can be hard to read CVs on, but can on Decoder Pro. Usually I can program the decoders on a programming track or by programming on the main, or via Decoder Pro.

[CSX Robert]

I don't know if all MRC sound decoders have this feature, but with at least some you can adjust the volume by "double clicking" the headlight, turning it off then on, or on then off, fairly quickly.  It only gives you three levels and mute, but it does give you a quick and easy way to adjust the volume and maintains the setting when powered off and back on.

 

[snjroy]

Yes, I don't hesistate to go low-tech when I have a problem!

I did dig up my MRC instructions for the 4-4-0. These CVs control the sound volume:

CV56: chuff (0-3)

CV51: whistle (0-3)

CV53: bell (0-3)

Default on these are 3 (!). So I would try setting them at 1 and see what happens. Of course, you might have another decoder type and it might not work...

Simon

 

[Trainman440]

snjroy

 

 

mvlandsw

If all else fails put a resistor in series with the speaker.

 

 

 

 

Or put some tape on the speaker, or on the underside of the tender to cover the holes that the sounds comes out from.

Simon

 

Lol its usually the other way around, with the speaker not loud enough!

 

[wjstix]

I've found the only way I can read CVs from an MRC decoder is using Decoder Pro. However, you should still be able to change CVs (unless you've somehow locked the decoder so no CVs can change - but I don't think MRC decoders have the 'lock' option?).

Sometimes programming on the main works better than a programming track for MRC decoders. If you can program on the main, hit F1 to ring the bell then change CV 53 to zero. If bell is still ringing, try changing CV 49 to zero. If the bell is still ringing, for some reason your system isn't changing the CVs. (If the decoder otherwise works OK, it's apparently not a problem with the decoder.)

Last resort try putting on programming track and change CV 125 to "1" to do factory re-set, then try setting CV49 to lower number.

[snjroy]

mvlandsw

If all else fails put a resistor in series with the speaker.

 

Or put some tape on the speaker, or on the underside of the tender to cover the holes that the sounds comes out from. I have an older Athearn-Roundhouse 4-4-0 with the infamous MRC decoder and I have the same issue. Works OK otherwise, after some other minor adjustments. It's a sweet little engine and it pulls like a champ!

Simon

[Remeyer53]

Some Athearn locomotives with the MRC sound decoders had an sound volume control that you could turn with a small screwdriver. In my case it was a 4-6-6-4 Challenger. The adjustment could be reached by removing one of the small hatches on the tender.

[mvlandsw]

If all else fails put a resistor in series with the speaker.

[RR_Mel]

What DCC controller are you using to change CVs?  Some MRC decoders won’t respond to some controllers.
I use the MRC USB adapter from my computer to my Prodigy Controller with JMRI Decoder Pro and it works great on all of my MRC decoders.


Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951



My Model Railroad    

 
Bakersfield, California
 
Aging is not for wimps.

[hobo9941]

Thanks for the reply. Myproblem is that no changes in the CVs actually changes the sound volume.

[hobo9941]

I still have a few MRC decoders that I haven't replaced. They are good runners, but I cannot lower the sound volumes, even when changing the CVs. Is there any way to lower the sound on these decoders.