# Been tinkering with N scale sound...reporting...



## Brakeman Jake (Mar 8, 2009)

Lately,I've been tinkering with some of my N scale articulated locos,installing sound decoders and experimenting with CV programming.In this process,I did learn a lot,having success with some and not so great results with others.

First,I installed new Soundtraxx TSU-4664N in both my Athearn Challenger and Big Boy...the installation is a breeze.However,I've experienced a slight difference between the two.

First,the Challenger...the original MRC decoder had given me some headaches so I had decided to replace the whole hardware so replaced the speaker with a somewhat smaller Soundtraxx speaker.Well the setup sounds nice but for some reason unknown to me,Decoder Pro has a hard time reading the CV's.It takes over an hour to do so.However,it programs easy and the loco is a jewel set like this.

Then,being satisfied with the Challenger,I retrofitted the Big Boy and,as per Soundtraxx's instructions,used the original MRC speaker.Being an 8 Ohms too,it should be OK.Well it is.I had always assumed they weren't of the higher quality,I had doubts but the BB does sound slightly better than the Challenger,wich is nice too.Is it the decoder or the speaker?I don't know.And a strange fact,this decoder gets its CV's read in three minutes while the other takes an hour...mistery to me.

Now...one clumsy thing I did.I've spent a whole night researching why I couldn't hear all these fantastic sounds Soundtraxx decoders give out.Rechecked mapping,re-wrote CV's,checked again to no avail...head scratching indeed.I was about to call quits when it struck me...I had had a glitch sooner and suspecting my DCS 200 was playing tricks with me,I had replaced it with my older generation DCS100 (still new) wich is an eight functions only unit.

I had planned on installing a pair of TSU-750's I have sitting in my two Cabforward's.But got faced with a problem...these things run really hot and the tenders aren't large enough to fit a decent heatsink in them,so I dropped the idea,fearing they might melt the plastic around them.These units run great with TCS DP2X decoders,so I'll leave them this way.Instead,I'll see if I can fit a 750 in a brass I have.Tender is larger and being metal,heat is no worry but these things have a special way to handle current...loco picks one track and the tender picks the other,wich means a conductive drawbar...another technical challenge.


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## NIMT (Jan 6, 2011)

Brakeman Jake,
All is sounding well on the sound front.
On the conductive draw bar question. I replace the draw bar with a non-conductive one, your already going to have to more wires running from the tender to the cab, Lighting, motor, so one extra wire for the power will not hurt you.
I install a plug between the tender and the engine to make life easier on the maintenance side of things.


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## Brakeman Jake (Mar 8, 2009)

Hi!...it's me again.In my last post,I said I wanted to fit a TSU-750 in a brass loco I had on hand.Well,I've done it...with limited success though.The loco is a Key Imports GS4 Daylight 4-8-4 that ran very nice on DC,drawing +/- .5 amps when stalled,so far so good.The decoder should handle it.

Then,removing the tender shell...plenty of room for the weight,decoder,enclosed speaker and the capacitor...project still going strong.

Then removed the loco shell...too bad,this thing has no light but good news,good space for routing the wires.Next step,a visit to the local electronics store to find LED's that would fit.Unfortunately,no available LED's that would fit but...the gentleman explained that,with great care,I might succeed in filing their contour to reduce their size.

Having functional headlight/Mars light was a major condition to the rest of the project.No working lights,no DCC retrofit.So back home I get at it.First re-drilled the light openings to the maximum diameter I could then I started filing the contours of the LED's while watching TV until they both fitted.I had filed enough I was pretty sure they wouldn't work any more but they did.

Then came the fitting of the decoder.While this loco uses frames to carry current,the motor is still insulated,with short wires to the brushes,so this part was easy and I didn't need to replace the conductive drawbar either.Simply make an opening to the front of the tender for wires and the instal is finished.In short,fitting the darn little LED's up front were 70% of the work.

Then came the part I've come to enjoy particularly lately...tinkering CV's.I needed to convert the headlight (white wire,installed in the lower opening) to a Mars light and re-assign the yellow wire (normally rear light) to an on/off function.It took me a little while to figure it out...OK...here's what I did...

Using Decoder Pro,I remapped the headlight to the Mars light function and also remapped the yellow wire to function five,making it an on/off headlight.I haven't figured out how to have a steady Mars light (turns off when shifting reverse),but since it's not much of a bug,it'll likely stay as is.

The sounds...just great.Is it the speaker enclosure used (1/2 in. Soundtraxx speaker) or the metal tender?Can't really tell,probably both.

The only drawback...this thing has terrible current pickup (loco/right-tender/left) so it runs quite decent at fair speeds but glitches all the time at creeping speed on less than perfect track.But guys,it can be done...I've done it...


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## NIMT (Jan 6, 2011)

Sounds like your trucking right along. I have run into the same problems with converting brass loco's to DCC. About the only help is to add a larger capacitor and better pick-up's (which is a pain in the back side)!
I just got in a ton of new LED's, all the way from super tiny 603 SMD LED's to 3MM all in warm white, perrfect for headlights and ditch lights.
If your going to do any more refits or installs give me a shout and I'll send you some up on the quick!


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