brass AT&SF M190 dcc and improvement

[Dirk Jan Blikkendaal]

Thanks a lot!
Realize now I posted 1 old/wrong picture..... removal of the raised SAMHONGSA on the underside of the powered front truck was quite crucial for troublefree operation.
On my model those letters could sometimes cause a short on turnouts (these letters hitting the diverging track)........ see 1st picture.
Thanks to Ron's posting of this thread I decided to add the front headlight  (small LED with 470K resistor) just a couple of days ago (2nd picture)......... I am happy!
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[peteski]

That is an interesting conversion Dirk.  Very nicely done.
I believe that on those trucks the gears also protrude slightly through the bottom cover.  So the raised lettering protruded even more (low enough to touch the rail?!  Wow!  How did you figure out that  the lettering was causing the short?

Also, 470k (lower case k) or 47000 ohm resistor would likely result in the LED barely glowing.  You probably meant 4.7k

[Dirk Jan Blikkendaal]

Hi Peteski,

I found out about the low lettering simply because the model shorted/stopped while crossing the diverging track on some turnouts with the powered truck over that spot/track....
Not on all turnouts but on a couple.... the lower deck of my layout is already in use for about 30 years using Peco Electrofrogs.... tolerances are probably quite critical on my model.... and although I make a point of good/accurate/level trackwork and checking/adjusting wheel gauge on all engines this happened to me..... happily problem solved!

The gears are not protruding below the cover plate...... just visible and easy to lubricate sparingly every now and then. For 1980 N scale those Samhongsa drives had really good slow speed and overall speed control in my opinion......

Regarding the LED: thats a type error.....sorry..... I used 470 ohm but thats too bright I agree..... on this older decoder there is no brightness adjustment like on present good decoders. So I added another resistor to adjust the brightness yesterday.....

[peteski]

Thanks for the explanation dirk.