Decoders
Most of the times the decoders from TCS Train Control Systems are used.
More recently, I started to use Zmodell decoders
TCS Z2 Decoder
The Z2 decoders with wires are used for the AZL locomotives with four digits order numbers and the Budd RDC (first run). These locomotives are DCC prepared. They have six soldering pads which are then connected with the wires to the decoder.
TCS AZL4 Decoder
The newer AZL locomotives with five digits order numbers are prepared for drop-in decoders. Two drop-in decoders are available: DZ123Z0 from Digitrax and AZL4 from TCS. Both have SMD LEDs on board for the head and rear lighting. The drop-in decoder of my choice is the AZL4 because it has two additional functions that can be used for illuminating the headlights. Additionally, it has soldering pads for connecting directly a LED without a resistor parallel to the front LED on the PCB. This is not described on the decoder information sheet, but it is obvious when looking at the printed circuit board. These additional features are very helpful for a good illumination of the headlight as some of the newer AZL locomotives have only very weak headlights.
I use the Lenz Digital DCC System. Unfortunately, the TCS decoders for z scale don't support the RailCom feature of Lenz (also known as bi-directional communication) nor the ABC technic (AutomaticBrakingControl).
Digitrax DZ123Z0 Decoder
As mentioned above the drop-in decoder DZ123Z0 from Digitrax is used with the
newer AZL locomotives with five digits order numbers. It has SMD LEDs
on board for the head and rear lighting. The pads which make the contact
with the chassis have solder on it. It has to be filed down in order to
fit into the chassis.
Zmodell ZDL-AZL-SD40-2 Decoder
The Zmodell decoders ZDL-AZL-SD40-2 (pdf) were released in Europe at the beginning of 2024 and in the US in spring 2024. They are specially designed for the AZL engines SD40-2 and SD40T-2. They featured bright LEDs and most of all an integrated power buffer which supplies power to decoders during times of power interruption due to dirty track or problematic track work. This leads to fantastic driving characteristics with uninterrupted slow speed and to no flickering of the lights. The digital decoder is based on Doehler & Haass® hardware and software technology (pdf).
Installation: Install the decoder with the four screws to the chassis. This gives a good electrical connection of the decoder board with the chassis.
Zmodell ZDL-AZL-01 Decoder
Zmodell universal digital decoder for AZL and Märklin/AZL models
The Zmodell decoders ZDL-AZL-01 (pdf) were released in Europe in summer 2024. They featured bright LEDs and most of all an integrated power buffer which supplies power to decoders during times of power interruption due to dirty track or problematic track work. This leads to fantastic driving characteristics with uninterrupted slow speed and to no flickering of the lights. And the bright LEDs make for example the ditchlights of the SD70ACe really visible, while with the other decoders you can't see them. The digital decoder is based on Doehler & Haass® hardware and software technology (pdf).
The Zmodell decoder ZDL-AZL-01 can replace the TCS decoder AZL4 and the Digitrax decoder DZ123Z0.
Installation: Even though the decoder is a drop-in decoder it doesn't drop in easily! The track pads above and under the board have solder on it. The solder has to be carefully and patiently reduced in height by for example filing so that it sits firmly in the clips of the chassis. Always check before continue to file.