By: Mark Mervine
Märklin® introduced the V80 locomotive (36080) equipped with a digital decoder and special motor. This locomotive is similar in construction to the 368xx series hobby locomotives. Like the hobby locomotives, however, the V80 is not equipped with sound. Many modelers believe that the sound component adds a new dimension to model railroading.
Recently, fellow chapter member Jeff Koellmer and I added a Loksound® v3.5 decoder to my Märklin® V80. This article describes how we accomplished the installation. The technique and identification of parts required are credited to a Mr. Lutz Hemmerich, whose information is posted on a website elsewhere. Our thanks go to Mr. Hemmerich for introducing us to this exciting solution. In addition to the 36080 V80 diesel locomotive, the parts needed for the installation were as follows:
a) Märklin/Trix® Part Number 611654, Circuit Board (equipped with a NMRA standard 8-pin plug).
b) LokSound® v3.5 Digital Decoder, ESU part number 524xx.
c) .63” double LokSound® speaker, ESU part number 50447.
These parts can be obtained from your Märklin® and ESU dealers.
An ESU® LokSound® programmer attached to a Personal Computer (PC) was also used to adjust the decoder’s settings once the installation was completed, but this can also be accomplished with other devices (your Märklin® 6021 Control Unit or Uhlenbrock Intellibox). Other tools required for the installation were a soldering iron, wire cutter, needle nose pliers and small screwdriver. We found that it helped to have two people working to aide in the de-soldering/soldering process (extra set of hands) as explained further below.
Step 1 – Remove the Locomotive Body
The first step in the process was to remove the locomotive’s body. There are two retaining screws that are accessible when the locomotive is inverted and placed on a work surface. Access to the motor and electronics was available when the locomotive chassis was set upright.
(Click Images to enlarge)
Step 2 – Disconnect the Headlamps
In preparation for replacing the existing circuit board, we disconnected the headlamps that were located at both ends of the unit. We carefully slid the ribbon cables from their respective sockets on the circuit card to permit easier access to the circuit board.
Step 3 – Replace the existing Circuit Board
The next step in the process was the most difficult, but was made easier with two sets of hands. First, we disconnected the power pick-up cables from the circuit board. There was one red wire and two brown wires soldered to each of three corners of the circuit board. We unsoldered these three wires and moved them out of the way for the time being.
We removed the circuit board from the chassis by first taking out the four retaining screws, and then by lifting the board/motor assembly out of the chassis. The cardan shafts leading to the driving wheels became unseated in this process but were easily reset later on. We found a small piece of double-faced tape between the old circuit board and the motor. With the circuit board/motor assembly now apart from the chassis, we gently pried the circuit board upwards to loosen the tape. The motor was attached to the circuit board by two “globs” of solder. While Jeff heated up both globs with my soldering iron, I applied gentle pressure on the motor to slide it away from the old circuit board (a little tricky..),. Once free, the old board was set aside.
The new circuit board (part a. listed above) was then installed by reversing the process of reheating the solder “glob” and sliding the circuit board into the position vacated by the old board. We put a piece of black electrical tape on the back of the new circuit board to prevent any potential short circuit between the circuit card and motor assembly. The drive shafts were reset and the new circuit board/motor assembly re-installed using the four retaining screws. The three power pick-up cables were re-soldered to the contacts in the respective corners of the new circuit board.
The end result was that a new circuit board containing an eight-pin receptacle now replaced the older circuit board. Since there is not much clearance inside the shell of the V80, the plug was cut from the new LokSound® decoder (Part b. above) and the eight wires were carefully soldered directly to the new motor circuit board’s female plug receptacle. Before continuing, we decided to perform a bench test. We placed the chassis with the new circuit board and LokSound® decoder on a special programming track. We used the ESU Programmer connected to a PC, to test out our progress and make sure all was working as anticipated. The new decoder worked flawlessly and each available function was checked in turn and the sounds were impressive!
Following the bench test, the chassis was returned to the work table. To complete the installation, the new .63” double speaker (part c. listed above) needed to be connected to the decoder. We unsoldered the two wires from the stock speaker and connected them to the new double speaker. We then soldered a wire between the two speakers and installed them in the supplied sound chamber.
Step 4 – Install the New Speaker and Decoder in the Chassis
We found it necessary to use a piece of tape to hold one end of the speaker sound chamber away from the drive train. The decoder was also a tight fit and it took a little trial and error to squeeze the speaker and decoder into the frame and have the shell fit correctly on the chassis.
Step 5 – Replace Locomotive Body
All that was left to do was to re-install the body on the chassis, place the locomotive on our layout and dispatch our creation while enjoying the sound of its engine and horn. After testing, I edited the stock sound file and added a conductor’s whistle and two station announcements; all controlled by function keys on our controller. Overall, we found the process to be straight-forward, quick and well worth the effort and small added expense.