Athearn FP7 Decoder Installation featuring the GEN-MB1 Motherboard with Keep Alive®, WOW121-Diesel Decoder and 28mm Speaker by TCS.
Athearn FP7 shown with the shell on prior to installation.
First, remove the front coupler box screw and the coupler box. Next, remove the rear screws as shown above from the rear of the chassis.
Gently remove the shell by pulling out on either side, separating the shell from the chassis and lift up.
Take care to allow the rear coupler to pass up and out from the chassis.
Shown with the shell off. Remove the wire leads from the original lighting board as well as the speaker housing and remove them from the chassis.
Trim and tin the wires as necessary to proceed with the installation. Make note of the wiring locations.
Attach the new GEN-MB1 motherboard on to the chassis and solder the track and motor leads to it.
Next, remove the original speaker shown above from it's housing and mount the 28mm Round WOWSpeaker facing into the speaker housing. This may seem counter-intuitive, but this permits the speaker wires to remain on the outside of the housing allowing for a solid seal all the way around. Because the speaker is mounted facing in there is less risk of getting glue on the speaker cone, but you should still be careful to avoid blocking the back of the speaker.
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.
Next, mount this speaker assembly onto the frame in it's original location, using hot glue to secure it down. Wire the speaker leads to the GEN-MB1.
Solder in the lighting connections from the shell to complete the wiring of your installation according to the included wiring diagram.
This mother board has a 1.5volt power supply to power all the original 1.5v bulbs that come with the Athearn locomotive.
You can now plug in your WOW121 decoder.
You can now reassemble the shell and coupler and your WOWSound equipped Athearn FP7 is ready to roll.
Important Soldering Tip
Please do not use any flux either liquid or paste on the mother board. Over time, the acidic properties of liquid or paste flux will begin eating away at the fiberglass PCB and will damage it. Use only Rosin-core solder or no-clean flux approved for electronics use.
TCS recommends the use of Kester "44" Sn63 Pb37, .015" diameter Rosin-core solder. Kester part number 24-6337-0007.
You can order this solder from the following retailers:
Digikey - PN:KE1110-ND
Techni-Tool - PN:488SO6775
Other solder tips
When stripping wire, only strip a tiny little bit of the insulation. Strip no more than a 1/32 of an inch. When the wire gets tinned with solder, the insulation will shrink back more. Try to not expose any more wire than 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
In order to keep the wires neat and prevent possible shorts, we recommend lacing the wires into a bundle using lacing cord. Lacing cord 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