Properly spoiled by my factory-installed sound engines, and boostered by David B’s tutorial, I have launched into a new project, and I thought I’d share my experiences as I go.
The subject engine is a Proto 2000 EMD GP38-2 in CSX colors. I had previously installed an NCE D13SRJ motor decoder. This engine has illuminated light boards. I had wired these to function outputs 2 and 3 so I could control them. The rumor was that these lightboard lamps were wired incorrectly on the factory light board/plug, and it was necessary to rewire them so they didn’t destroy the decoder. This decoder does not have onboard current limiting resistors, so I actually changed all 4 lamps to 13v lamps. By the time I unwired all the lamps, I decided to discard the factory plug and hardwire the decoder.
I purchased a couple sound decoders at last weeks train show. They were the Digitrax SFX0416 and SFX004. The former is a sound and 4-function only decoder. The latter is a Soundbug. The Soundbug does not need to be used with a Soundbug enabled motor decoder, but can be wired to the track rails only. It has no function outputs. After some testing, I decided to put in the SFX0416. Each of these came with a 1.1 inch speaker. My GP38 has a very narrow shell, and I couldn’t convince myself the factory speaker would fit, so I am going to use a mini-oval speaker from Tony’s. I made a speaker enclosure out of styrene and adhered the speaker inside it with a narow strip of double-sided foam tape. Someday, this tape will probably fail, but right now it seems stuck pretty well.
The photo shows the frame after I “hacked” a section out for the speaker enclosure. I still need to find a home for the capacitor and make sure I have room for both decoders under the shell. I made the cutout with a coping saw - a little “primative Pete-ish”, but it worked.
Ditch lights… It’s like a sickness, isn’t it. [:)]
The tricky part was figuring out how to run the number boards off function outputs, but not let the function buttons on the throttle affect both sound and lights. I ended up mapping the function 3 and 4 outputs of the NCE decoder to come on when F0 (lights) were activated on the throttle. That way, the number boards dont turn on and off when I use the bell and horn sounds.[:-^]
Here is my opinion of P2K sound installs(alot of you might cringe when I say this…); I remove the extra weight and deposit it into the bin. I find that it is complete overkill for our scale, and with the free-rolling offereing today in terms of rolling stock, the uber-weight is unessesary. The worst case senario being that you need to double head your trains. That being said, with the weight removed, it lends itself to alot of extra room for the speaker. The weight can be added back on if nessesary with peel-and-stick weights in the future.
I’m inclined to agree with you. I don’t do this professionally, so I don’t mind putting in the time. It took me a couple hours to get the weight cut to my satisfaction. It would have taken only about 30 seconds to ditch it completely. The weight does perform another task: It supports the lights in the proper orientation to the fixtures in the shell. I know I could have worked out another way to support the lights.
Just for fun, I weighed the weight (after removing the cut out section). It was 7 ounces. I have a bit more cutting to do on it. Maybe I’ll be less conservative. Just doing my best and trying to minimize my impact on the engine.
David, if you get a chance, let us know how you eliminate the crossing gate sounds (F7 and F10 ) in the Digitrax decoders. If you did in another thread, sorry, I missed it.
To eleimate the F7 and F10 sounds, you need to rewrite the .sdf file in your .spj file. Ive done this many, many times and would be happy to email (for YOUR use only) a copy of a project that I would use for the GP38 (I am assuming you have the PR2). I think you would enjoy the sounds.
Done! Here’s a peek under the hood and the final result on my turntable…
I built the speaker enclosure from .020 sheet styrene. The speaker is inside the enclosure, mounted and sealed (hopefully) to the bottom with double-stick foam tape. I punched a couple holes with a holepunch for the sound to get out from the front of the speaker.
I modified the weight to cut out a spot for the enclosure, and made the cutout over the motor longer and deeper to make room for the decoders and wires. The lamps have all been changed to 13v, 30ma bulbs compatible with the primary NCE decoder. The challenges are mostly mechanical: making room for the speaker, capacitor and decoders, and then routing the wiring. As you can see, there are various layers of tape holding things in place.
When I do a decoder install, I tend to test in stages. In this case, I wired the motor first, temporarily tacked on the rail power, and tested the motor. Then the lights, the speaker and capacitor, and finally the rails, testing at each stage.
I’m not really sure how most folks deal with a dual-decoder install. The strategy here is to assign unique short addresses and a common long address. I figured if I need to tweek a CV, I should be able to switch both decoders to their short addresses (CV29 = 6), make the adjustment in ops mode by addressing the decoder I want with the short address, and then change both back to the long addresses (CV29=38). In practice, I may have trouble doing this. The sound decoder did not want to switch between long and short addresses in ops mode. At any rate, I set the unique short addresses before wiring the two decoders together. I considered attempting to lock the decoders before wiring together, but I didn’t do it. The worst case is I need to disconnect power
I figured it out! [:D][(-D] [:D][(-D] [:D][(-D] [:D][(-D] [:D][(-D]
Most functions on the PowerCab, like F0 (lights), F1 (bell), etc. are not momentary. Press them once and they turn on. Press them again to turn them off. In my case, the grade crossing sounds (and a couple other less obnoxious ones) were occurring at decoder power on because I had pressed them to actuate the sounds ONCE. I needed to toggle them back off. NO MORE OBNOXIOUS GRADE CROSSINGS EVERY TIME THE DECODER RESETS! YEAH!
I suppose this is sort of what previous advice was talking about. I just didn’t get it.
