Massoth decoder issues

[richand26mhz]

Hello, i have acquired a couple of decoders that are no longer working. They were previously working but seems to have gone wrong. One of them does nothing but it started with the engine just charging off at full power until it stopped altogether.

From looking at the chips with my phone i could see what i believe may be the issue and asking the question can it be repaired easily?

From what i can see there may be a potential issue with the orange tube to the right of D+ looks burnt and maybe the chip between D+ and M- has a bubble on it.

Are the parts replaceable?





thanks Rich

 

[Greg Elmassian]

Replaceable yes, but you need to know the part numbers... looks like the motor outputs were shorted to the track leads, the most common mistake made.

Greg

 

[ntpntpntp]

The "bubble" in the chip package is a sure sign of a blown output FET, and there may be other blown outputs too (look for other slight bubbles or dark spots on the other chips in this area of the decoder). Is that such a heat spot on the bottom right of the chip pictured?



I did once replace a FET chip similar to this on a Lenz decoder some years ago. As Greg says, you'll need to be sure you can identify the chip and that you're confident with soldering such small component legs. To be honest, although my repair got the loco working again, the decoder was still never "quite right in the head" so I junked it.

 

[richand26mhz]

Thanks for the information. TBH i think they are just scrap.

 

[PhilP]

Thanks for the information. TBH i think they are just scrap.

Very probably.. You *could* send them back to Massoth in Germany, but they would probably be beyond economic repair?