Athearn GP50 Decoder Installation featuring the GEN-MB1 Motherboard with Keep Alive®, WOW121-Diesel Decoder, and GEN-SH1 WOWSpeaker Kit by TCS.
First, remove the coupler box screws and the coupler boxes from both ends of the locomotive.
With the couplers removed the shell should lift right off the chassis.
Remove the original lighting board from the chassis and remove the wires from the board tabs.
Next, we will remove the front weight so we can install the motherboard. To do this remove the two screws (highlighted above) from the front weight and lift it off.
Beneath the front weight are track wires that were held in place by the weight. To make sure that the wires don't bind up in the drive mechanism they were taped down with Kapton Tape.
Clip the the GEN-MB1 into the motor plastic motor clips and solder the track and motor connections to the board.
Next, we will remove the rear weight so we can fit a speaker.
To remove the rear weight simply unscrew the screws highlighted above and lift the weight right out.
With the weight removed you can mount your 35mm x 16mm WOWSpeaker in the GEN-SH1 speaker housing and screw the housing to the frame with the screws you removed from the weight.
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.
Solder the speaker and light wires to the motherboard according to the diagram on your motherboards manual. This mother board has a 1.5volt power supply to power all the original 1.5v bulbs that come with the Athearn locomotive. This motherboard can be configured for LED operation as well, the mother board has built in current limit resistors for LED use. Consult the wiring diagram for LED use.
All the original 1.5volt bulbs supplied with the Athearn loco were used. The "FL" solder pad is the forward 1.5v solder pad for the front lights. The "RL" solder pad is the reverse 1.5v solder pad for the reverse lights. The ditch light bulbs are connected to the solder pads marked "1", "2". The solder pad marked "1.5V" is the common power source for the bulbs.
Finally, install your WOW121-Diesel decoder on the GEN-MB1 motherboard, replace the shell (it should slide over the installation easily), and replace the couplers on the shell.
Your WOWSound equipped engine is now ready to run!
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