This installation is for a HO Scale Bachmann F7A using a TCS WOW121 Diesel Decoder, AK-MB1 Motherboard with built in Keep Alive®, motor mount
and 28mm WOWSpeaker.
Kit Coming Soon! We are in the process of assembling all the items shown here into a new WOWKit. Please check back here to see the new WOWKit when it arrives. Shown prior to installation.
To start off this install, we must first remove the front coupler screw highlighted above and it's housings. With the couplers removed, remove the four screws highlighted above located underneath the chassis. While gently pulling outwards at each end and along each side of the frame, lift the shell off of the frame. Take care to release the handrails as you lift off the shell so they don't break.
The Bachmann F7A shown with the shell off. Remove the two screws highlighted above as well as the wires from the original lighting board and remove it from the chassis.
With the lighting board removed, remove the two screws and the small plastic platform as highlighted above. Trim, tin or lengthen the wire leads as needed and using small lengths of TCS 3/32" and 3/64" shrink tubing, insulate these solder leads.
Clip the 3 caps and the two other components highlighted and remove them from the motor. These will not be needed with this installation. Replace the motor wires with new leads.
Shown with the caps properly removed. Next, remove the two screws holding the speaker enclosure and remove this and the speaker inside. They will not be used in this installation.
Shown with the speaker removed.
Using double sided foam tape, mount the AK-MB1 to the motor mount.
Using the same tape on the bottom of the motor mount, secure this assembly to the top of the motor.
With the AK-MB1 in place, solder the motor and track pickup leads to it.
Using a small amount of hot melt glue, mount the 28mm WOWSound speaker to the frame as shown. NOTE: You must be very careful to avoid getting glue on the speaker cone. Glue on the speaker will ultimately cause it to produce no sound and fail.
You can now plug in your 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 www.digikey.com. We use part number 802534B BK032-ND
Now you can close up the locomotive and reinstall the coupler assemblies. Be sure to be mindful of wire routing and reassembly of the shell as to not damage
or foul the installation. Your Bachmann F7A is now WOWSound equipped and ready to roll!
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
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