This installation is for a HO-Scale Atlas DASH 8-40B using a TCS WOW121 Decoder, AS-MB2 Motherboard, KA4 with built in Keep Alive™
and 28mm WOWSpeaker.

This was performed by our friends from DCC Xpress installations.
They offer high quality WOWSound installations for a flat rate complete with free return shipping!
You can find them at:

These items are available in the WDK-ATL-8 which was used for this installation.
AS-MB2 Motherboard WOW121-Diesel Decoder KA4 Keep-Alive™ UNIV-SH2-O WOWSpeaker Kit
Click here for more information on the WDK-ATL-8 and the rest of the WOWDiesel Kits line.

Important Soldering Tip:
Please do not use any flux either liquid or paste on the mother board. It will damage it. Use only Rosin core solder approved for electronics use.
We recommend to use only Kester "44" rosin core, SN63PB37, .015" diameter, part number 24-6337-0007.
This can be ordered from Techni-Tool under Techni-Tool part number 488SO157

HO-Scale Atlas DASH 8-40B prior to installation.


To start off this install, we must first remove the front and rear coupler screws as indicated above and their housings.
Once that is complete, grasp either end and along the shell and gently pull out to lift it off of the chassis.

With the shell off, we can now remove the original light board. Remove the wires from the board and the board can easily be removed.

Shown with the factory light board removed. We can now attach the AS-MB2 to the chassis.

Shown with the AS-MB2 mounted and the JST connectors installed.

Next, using double sided foam tape, mount the KA4 Keep Alive™ on to the rear of the front weight as shown and solder the wires to the AS-MB2 motherboard
according to the included wiring diagram. Remove the rear weight plug at this time to facilitate mounting of the speaker assembly.


Mount the 28mm speaker into the frame port as shown and solder the speaker wires onto the motherboard speaker pads.

Using a file, cut a small notch in the weight on the opposite side of the speaker as shown above in red, to allow the speaker wires to easily pass through and re-insert this weight into the frame. It is important to do this in order to retain as much rear weight as possible and enhance the sound output,

You can now plug in you WOW121 decoder.

Lastly, in order to keep the wires neat and prevent possible shorts, lace the wires into a bundle using lacing cord, which is a wax impregnated string 
used for wire bundling and making harnesses. There are many choices of lacing cord available from Digikey
We use part number 802534B BK032-ND

Your DASH 8-40B in now WOWSound equipped and ready to roll!

Other solder tips: When stripping wire, only strip a tiny little bit of the insulation. Strip no more then a 1/64 of an inch. When the wire gets tinned with solder the insulation will shrink back more. Try to not expose any more wire then half the length of the solder pad at most. In no case should solder or exposed wire wire ever be outside the boundary of the the solder pad you are attaching a wire to.
Click here for important information on properly Stripping and Tinning wire

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