Anybody see a reason that in a A-B-A setup with 2 DCC A units (only one with sound) and a dummy B, that the sound unit couldn't be placed either leading or trailing?
mreagantAnybody see a reason that in a A-B-A setup with 2 DCC A units (only one with sound) and a dummy B, that the sound unit couldn't be placed either leading or trailing?
No. Why should it? The sound is being heard anyway and the lights should work in the same way as if you would run it alone.
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I've seen it done before by Joe Fugate on his layout. I frankly like the idea for things like ABBA setups. Only thing is, I would put the sound unit in the dummy B unit so that the sound comes from the center of the consist instead of one of the extremes. But thats just me.
Good Luck with it!
--Jake
I have an Athearn A (powerd) and B (dummy). I have a moter DCC decoder in the A unit and am installing a Digitrax sound only decoder in the dummy. I am wiring one of the B unit function leads to a light to facilitate programing the sound decoder.
I have purchased some old Athearn BB SD40-2 dummy units which I will be putting sound in only. I have ordered NWSL wheels to replace the plastic dummy wheels. I will run the dummy units in 3/4 unit lash-ups with powerd units. I got this idea from Joe Fugate.
Jim, Modeling the Kansas City Southern Lines in HO scale.
I'd put the sound in the B unit. Not to make it come from the middle of the consist, but simply because a non-powered B unit hs space for a HUGE speaker and enclosure. Or more than one - Bruce at Litchfield used to have a picture on his site of one with THREE speakers, two large ones plus a crossover and a small one for the highs. I once had a spare Stewart F7B I was doing this to - those are easy as the non-powered dummy units still have metal wheels and the metal sideframe plates for power pickup - you just need to solder wires to the plates. Plus the frame is metal so they have enough weight to make good contact witht he track.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks for the quick feeback. I thought it would work O.K. Putting the sound in the B is not an option, at least for now, as the sound is in the A--a BLI F7. The issue arose for me because the other A is a very nice P2K E8 and although I've seen E's running off the lead behind an F or FP in passenger livery, I'd sure like to showcase the E8 on occasion.
See my follow-up question about decoders for these units coming up in a minute.
If you've only got one sound unit in a consist, be sure that you understand the limitations of consisting with your DCC system. Depending on your system, you may need to do some special decoder programming to let you use the horn and such while running.
I have a Lenz system, which lets me run a consist either from the consist address or from any of the individual unit addresses, so I usually just run from the sound unit's address. If I've got a B-unit, though, I need to do something different to get the right headlights on and off. I haven't gotten around to messing with the function mapping for "advanced consisting." This was described in MR a month or two ago, and it might be worth a look.
It takes an iron man to play with a toy iron horse.
Would'nt the sound equiped loco start at a higher voltage than the one without? You'd have to do some adjusting CV's to get the locos to start at the same time.
Santa Fe all the way! Would'nt the sound equiped loco start at a higher voltage than the one without? You'd have to do some adjusting CV's to get the locos to start at the same time.
Generally not on DCC. This is only an issue in DC, because the sound decoder needs 5+ volts to start making noise. Since there's always power on the rails with DCC this is no longer an issue. Of course there will be variations between different decoders, and different brands of locos will have different motors and gearing and may not run together without some adjustment, but sound units with good motor drives will start moving at speed step 1. Speed of movement will depend on the motor and gears.
When consisting in DCC, one should expect to need some amount of speed matching between the powered units. This is true whether the engines have sound or not. Even two of the same model from the same manufacturer with the same decoder typically need tweaking to get them starting and moving together.
rrinker I'd put the sound in the B unit. Not to make it come from the middle of the consist, but simply because a non-powered B unit hs space for a HUGE speaker and enclosure. Or more than one - Bruce at Litchfield used to have a picture on his site of one with THREE speakers, two large ones plus a crossover and a small one for the highs. I once had a spare Stewart F7B I was doing this to - those are easy as the non-powered dummy units still have metal wheels and the metal sideframe plates for power pickup - you just need to solder wires to the plates. Plus the frame is metal so they have enough weight to make good contact witht he track. --Randy
Randy you couldn't be more correct, I have tow permanent lash ups and A-B-B-A Proto H2K set up all powered and all with sound and a Stewart A-B-A with both A units powered and each having sound but the speakers are mounted in the dummy B unit and it sounds awesome much better then the Proto set up. I will admit though when the train passes you can can hear a determinable difference of four vs two but the bigger better quality speakers and enclosures more then make up the difference.
Just to clarify a little, it doesn't really matter so much where the sound decoder is, as where the speaker is. I've done a couple of A-B sets of F's where I've had a sound and power decoder in the A unit, and run two wires (thru the windows in the doors at the ends of the units) back to a 1" speaker in the dummy B unit. With all that room you can use a big speaker and enclosure (or two speakers / enclosures) and get great sound. In an A-B-A set, if only one has sound, it would be best to have the sound come from the B unit I would think.
If it's a "semi-permanent" A-B-A set, with drawbars between, you could put sound & power decoders in BOTH A units, and run wires back to two 1" speakers in the B unit - one at each end.
If you REALLY want to go nuts, a B unit has enough room for TWO decoders - so if you run A-B-A sets, put a decoder for an E unit (two 567's) plus an F, and have 3 motor sounds. Or run A-B pairs with the B having an E unit decoder, then if you run two sets as A-B-B-A you'd have 4 motor sounds for 4 units.
Yes, this is extremely out there and crazy.