# LMS 3990 Electrical schematic



## bfjou812 (Jun 1, 2020)

Does anyone have/know where I can get a detailed electrical schematic for the LMS 3990? I'm specifically looking for the pin out of the plug. I have some parts laying around and since there isn't anything else going on I thought I'd try to piece a tach together to kill some time. Thanks in advance.


----------



## higgite (Jun 2, 2020)

Have you given LMS a call? I don't know if they would have a point to point diagram or not, but they're pretty helpful folks.

Tom


----------



## bfjou812 (Jun 2, 2020)

I have not called or got in touch with them. I checked their website and from what I could find they don't list anything for that model. I'm going to try later this afternoon.


----------



## Tio Loco (Jun 2, 2020)

Check this out....



			Macpod LLC: Hacking the SX2 Mini Mill - (Adding a reverse switch and reverse engineering the tachometer port protocol)


----------



## bfjou812 (Jun 3, 2020)

Tio Loco, Thanks for the link. I may wind up going that route.
I did get a response fron Chris @ LMS. He sent me a schematic of what I was asking for and very helpful. Unfortunately it seems that the plus is set up for their brand of tach only and to try using that would not be an easy task.  So looks like I need to explore other avenues.  Thanks for your help.


----------

