Digitrax DH127MT | Series 7 Mobile Decoder | HO Scale

The Digitrax DH127MT is a Series 7 HO mobile decoder built on the 21-pin MTC connector. If your locomotive has a 21MTC socket - common on European-built and many newer North American models - this drops straight in with no soldering and no harness to route. One amp continuous, two amps peak, with two FX7 function outputs at a generous 300mA.

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• 21-pin MTC socket (21MT) - plugs directly into any 21MTC-equipped HO locomotive, no soldering required.
• 1.0 amp continuous, 2.0 amps peak - comfortable for single-motor HO diesels and steam.
• 2 FX7 function outputs at 300mA, enough headroom for incandescent bulbs as well as LEDs, with effects like Mars light, ditch lights and beacons.
• Series 7 platform with back-EMF speed stabilisation for controlled slow-speed switching.
• Standard NMRA DCC - runs and programs on any DCC system, not just Digitrax.

How do I know if my locomotive takes a 21MTC decoder?
Pull the shell and look for a 21-pin connector on the circuit board, arranged in two rows with one pin position blanked off as a key. If you see an 8-pin or 9-pin socket instead, you need a DH127P, DH127PS or DH127D.

Which way round does it plug in?
The blanked pin position keys the connector so it can only seat one way. Seat it square and do not force it - a bent pin is the usual cause of a decoder that will not respond.

Does it have sound?
No. This is a motor and function decoder. For sound in HO, look at a Digitrax SDXH series decoder or a SoundTraxx unit, plus a speaker.

Do I need a Digitrax command station?
No. It is a standard NMRA DCC decoder and works on any DCC system.