Auscision 45 Decoder Installation.


I fitted a Soundtraxx Tsunami AT-1000 12 Cylinder Alco 251 decoder as this is a “straight” swap for the installed Light Board, making it easy to add sound.


For the purists amongst us I would recommend a Loksound V4 from DCCsound, loaded with their recorded sound project, when available.  See: and use the method explained at the bottom of the page for installing a speker.


Installing the AT-1000.


1. Remove the 45’s body by removing the 2 Couplers and 4 screws (2 each side of the Coupler).


2. Remove all wires from the Light Board Tabs and cut the wires in the centre of the board going to Headlight/Marker light On/Off Switches in the Fuel Tank. Remove and discard the Light Board. Trim the Tank Switch wiring.


3. Using a pair of larger Side cutters, not your small sharp ones you use for decoder installations and cut off the 6 Lugs as shown below. These are not necessary and provide more clearance for fitting the “electronics”. Using side cutters instead of the Dremel, eliminates any fine metal from getting into the mechanism and it is easier.



Note: As shown above, the Fuel Tank has already been dislodged, see later.


4. Apply some tape to the underside of the AT-1000 or make a styrene strip to insulate the decoder. Attach the decoder to motor, I used some Blu Tac.


5. Solder the loco’s wires to the appropriate Tabs using the decoder’s Instruction Manual as shown below.


NOTE: The Red and Black bogie Pick Up wires are SWAPPED OVER from front and rear. That is, connect the Front RED wire to the decoder’s Tab 1 and connect the Rear BLACK wire to Tab 10 (on the same “side” of the decoder). For the L/H side Front BLACK wire to Tab 4 and Rear RED wire to Tab 7. If you connect both red wires to the R/H side and the black wires to the L/H side, you’ll get a short circuit.


6.  The 4 wires from each of the Lights Boards are to be connected to the decoder’s Tabs as follows:


            Blue and Purple - Function Common – Tab 2/9.

            White – Head/Marker Lights Negative – Tab 3/8.

            Orange – Red Marker Lights - F5/F6. The wires may need to be lengthened.


The Headlight and White Markers illuminate together.


NOTE: There is NO NEED to install Resistors for the LEDs. Three 4.7 K resistors are already installed on the Light Boards, for the LEDs, making the light quite bright. Adding extra resistors may dull the lights to your desired effect – experiment here.


7. With judicial shortening of the included 220 uF Capacitor leads, I located the Capacitor under the decoder, on the on the “ledge” above the forward Flywheel.

Alternatively remove the Capacitor leads from the AT-1000 and then unsolder them from the capacitor. Clean out the decoder’s “+ & -“solder pads where you disconnected the two leads from, with some De-soldering Wick. This allows you to solder in the capacitor into the now cleaned out holes, facing rearwards (over the rear flywheel), for a better connection.

NOTE: If you do not install the 220 uF Capacitor, the decoder will not have ANY form of “sound” stay alive (there is NO Motor stay alive provided by the 220 uF capacitor) and it will shut down the sound at any hint of dirt and obviously stall if the loco does not “coast” over the dirt/power interruption. I also have had instances of not being able to read CVs, without this capacitor fitted, in other AT-1000 installations. If wanting to install the TCS Keep Alives or other similar units, see my “alive” page, at:


8. I removed the Speaker Box and installed (Blu Taced) an 18 mm MRC Round Speaker that is fitted to an enclosure already, to the Body, facing down below the Fan ensuring that it will not foul the body/decoder, when replacing the Body. To make a 35 x 16 mm speaker fit from Soundtraxx/QSI, you’ll need to modify the speaker or the supplied enclosure.


I have tested on my 45s and 48s, a 15 x 11 x 8 mm Sugar Cube speaker PLUS the appropriate Baffle, from Streamline Backshop at:


I have added a photo and details at the bottom of this page of the final speaker installation using a Sugar Cube speaker from Gwydir Valley Models.


9. Handling the mechanism while installing the decoder, the two thin Spigots (square pieces in the two body scrapped sections in the photo) securing the Tanks to the body are easily broken. I “broke off” both of my Tanks. I filed the spigots off the Tanks so that they can be glued in 4 places, as shown below. I used 5 Minute Araldite. I also scrapped the paint off the body. Now they stay connected irrespective of who is handling the loco.



10. Place the 45 on the Program Track and attempt to read CVs, say CV 1. If it reads “3” then the decoder is installed without any “shorts”.


11. Program your loco as desired. Out of the box, all you have to program is the desired 4 digit address and it works.


With ALL of my Tsunamis, I program for what I consider, better operation and sound, using Decoder Pro:


Adjust the middle and upper frequency bands of the Equaliser (4 in total to max (255)). In my opinion this makes a “better” and louder sound.

I then adjust the volume to about 80 out of 255. Adjust to you desired volume.

Note. If using Sugar Cube Speakers, crackling (distortion) is evident at too high a volume.

I also reduce my Top Speed to about 30 MPH using a Speed Table, see below.

Note: Soundtraxx do not support CVs 5 and 6.


To see how I speed match ALL of my locos including the 45, see my “Speed Matching” blog entry at:


This is a guide on how to install a Tsunami AT-1000. Other types/brands can be fitted with the appropriate changes. As I don’t have a 21 Pin decoder, I cannot see if anything has to changed but be careful, the 21 Pin can be installed in REVERSE and may be damaged if the loco is placed on powered layout (not the Program Track).


Installing a Gwydir Valley Sugar Cube Speaker or similar type.


1.      Remove the supplied Speaker Enclosure.

2.      Cut an appropriate sized piece of plastic (yellow in photo) and secure it with the two screws removed in Step 1.

3.      Seal the speaker in the supplied timber enclosure, the small amounts of Blu Tack between speaker and enclosure, at the “ends”.

4.      Secure the Speaker/Enclosure to the plastic.

5.      Most importantly jam/secure some Blu Tack around the speaker enclosure. This reduces the vibration of the speaker enclosure.

6.      Apply some electrical tape to the Fan opening inside the body to “block up” this outlet/vent.

7.      You’ll be surprised how much difference to sound quality and volume applying the Blu Tack and tape makes.

8.      Have the loco on the track and making sound, it will sound “tiny” and distorted. Blow the Horn etc and this is with the speaker in an enclosure.

9.      As you lower/fit the body, the sound improves out of site. Blow the Horn and WOW what a difference. The body acts as some sort of “amplifier/filter etc”. So much for all the theory.

10.  As with all of my Soundtraxx Tsunami installations, I adjust the Equalizer settings, usually done with Decoder Pro but for those of you that don’t use Decoder Pro, the CVs are: CV 153 to “7”, CV 157 to “250”, CV 158 to “255”, CV 159 to “255” and CV 160 to “255”. You’ll now have to reduce the overall volume to your desired level - CV 128 to between “1 and 255”.