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Kato SD 90 and 40-2 Track and electrical/DCC
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Super User 808 posts duckdogger Super User 808 posts
duckdogger
This is about a Tsunami install in these models.
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duckdogger Super User 808 posts
duckdogger

Kato SD 90 and 40-2

Both of the models have boards which differ from those of the Kato SD70 Mac. The 40-2 is of the vintage where the track feeds to the light board are via copper stops beneath the running boards. The 90 board is much longer and the motor feed is different, too. The Soundtraxx site refers to the standard KT series for these models so I presume we just make the modifications needed to adapt the Kato to the standard KT board?
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dmitzel Regular poster 276 posts
dmitzel

I'm interested in this question

I also have a pair of Kato SD90MACs on my UP Burlington Sub roster. No Kato SD40-2 units, however - just a pair of UPY SD38-2 engines for yard service, a couple of Kato WC SD45 locomotives for transfers and other than four F40PH's the rest of my roster is four Proto 2000 GP38-2's for locals. I'm waiting on Bowser's Canadian SD40-2's for a pair to run in SOO transfer service.

I've been building an Excel table for all my engines - to determine which decoder will be best. I plan on starting out with the Soundtraxx model 828062 TSU-KT1000 for Kato HO SD38-2 for my first installation - to try out sound on a first locomotive while using it to test trackwork as I build.

I'm not sold on sound for the whole roster - I figure the yard switchers and perhaps the "screamers" (the Metra and Amtrak F40's) are best suited for sound. The remaining engines will most likely get "mute" decoders, which will help manage the overall cost too. The TCS 1335 model DP5 decoder seems promising here, but I'm interested in hearing what others are using.

 
D.M. Mitzel
Div. 8-NCR-NMRA
Oxford, Mich. USA
Visit my layout blog at  http://danmitzel.blogspot.com/
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duckdogger Super User 808 posts
duckdogger

More thought on the Tsunami KT1000 boards

Now that the fog of too much Thanksgiving Day turkey has passed, the connection differences are minor. But it does beg the question, especially of Kato, why are they not standardized?

On the SD-40-2 (early run) I will wire the TSU to the truck lugs and bypass the copper strip completely. Likewise the motor leads are thin copper or brass and can be shaped to mate with the board. Worst case scenario is to solder a feeder from the motor lead and solder to the board. SImilar approach for the SD90.

Many installs on Kato units such as these involve setting the speaker on the decoder board  (as the motor sits low in the fuel tank, there is room to spare) and firing upwards. The result is very muted sound even at a full volume setting of 255.

A better practice is to mount the speaker on to the vertical frame lugs at the rear truck and fire down through the opening for the gear tower.  The caveat is the speaker enclosure height caps at about 10mm to 12mm due to the light tunnel and its mounting lugs. This applies to the SD40-2s, SD70s, and the SD90.

For instance, a RailMasters' 16x35 oval speaker with a 10mm deep enclosure produces great sound in this application. Ulrich carries a 10mm tall enclosure for this speaker. I used 4 tiny dabs of bathroom silicone to attach the speaker to the frame. Even then, I removed the rear light tunnel to make sure there was no interference. I simply relocated the LED to the lens where it enters the body. I secured it with Faller Expert cement (high styrene content) and ran wire back to the decoder leads.

Of course you can make your own enclosure to the 10mm height from styrene. I tend to avoid this as my enclosures look as if they were made by Andy Warhol on a 6 beer buzz. Another option is to trim the frame lugs with a Dremel, a hack saw blade, a jewelers saw, or an expensive end mill. I cut mine with a jewelers saw. Not fast, but effective. And not that much slower than the Dremel.
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duckdogger Super User 808 posts
duckdogger

Update

I have now completed 3 Katos, all SD70s, and modified the frames on 4 more. For cutting the vertical lugs, my process evolved to a small hobby hack saw with metal capable blades. It took about 3 minutes per lug. The Dremel and jeweler's file proved way to slow -about 30 minutes due to heat build up, blade breakage, etc. but maybe I was a factor, too. The original speaker was a 16x35 from RailMasters in a 10mm deep enclosure. Mounting is up in the hood body firing down. This required removing the light tunnel, cutting the LED from the Tsunami board, and wiring it directly to the light lens where it attaches to the body. The other 2 Katos use the same speaker but with RailMasters 14.5mm deep enclosure (according to Jeff at RailMasters, this is the only body he has for this specific speaker). Mounting and light remounting are the same. But the sound is much stronger in the 14.5mm deep enclosure. The turbo sound is very shrill at idle and the lower range speed steps. I reduced this via CV153 at 7 and then tweaking CV158 - 160. The values I used for my operating environment yielded a -12db cut in the 1000, 2000, and 4000 HZ frequencies. Yours ears may be different. But the sound is deeper as the exhaust can now be heard over the turbo whine.
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K-Pack Regular poster 397 posts
K-Pack

Speakers

Are the speakers you are referring to the DSM-8 or the smaller, non-reflex speakers?  I'm unfamiliar with Kato SD70s but I'd assume you'd have enough space in the back to get a DSM-8 in there.  Glad the installs worked for you!

-Kevin

http://www.protomodeler.com

http://theweatheringshop.com/kevin.html
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duckdogger Super User 808 posts
duckdogger

Katos have less room than you might think.

I did not use the DSM-8 in the Katos because I thought I would not get the benefit of the larger speaker due to the restrictive opening dimensions in the frame. I used a RailMasters' 16 mm X 35 mm in a 14.5 mm deep enclosure. The DSM-8 is my choice for Genesis hood and cowl units such as SD45-2 and FP45 . The abundance of roof openings allow the speakers to shine.
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Prof_Klyzlr Moderator 7,962 posts
Prof_Klyzlr

Headline : "EQ saves day, Small Speakers exonerated..."

Dear Duck,

Quote:

 I reduced this via CV153 at 7 and then tweaking CV158 - 160. The values I used for my operating environment yielded a -12db cut in the 1000, 2000, and 4000 HZ frequencies ... the sound is deeper as the exhaust can now be heard over the turbo whine.

Congratulations, you have just discovered the audio processing known as "EQ"!

Seriously, what you've done is drop the relative level of the "high" frequencies that the TSU is capable of, 
and are now letting the power amp stage use more of it's available power to focus on pushing the bottom end/ low frequencies...

(for those reading along, NB that Duck didn't change the speaker to overcome some percieved "never going to be big enough to reproduce low frequency sounds" issue,

but rather he tweaked the source signal being played back 
in concert with his speaker selection. enclosure, and mounting,
to get the desired audible result!)

It's not rocket science, but it is "Audio 101", and the results can be amazing...

Happy Modelling,
Aim to Improve,
Prof Klyzlr

 
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