Pulse speedometers?

What railroads used the Pulse sppedometers in their locomotives? They are the ones that use lights instead of a needle to indicate the speed. To my knowledge only Illinois Central used them, they are in everthing from the SD40-2R (rebuilt SD40) to the former BN SD40-2's and 40-3's (did BN use Pulses?) and the SD70's. I guess they are also in the GP38's and GP40's as well.

I did find a pic of one, so those completley clueless will know:


(this was taken in the IC 6108, a former BN unit.)

I have seen them, on most class-1 equipment, at some point in time. That duplex, LED speedo, is really nothing special. I would imagine the railroads buy what is available, from a recognized manufacturer, at the best price. They seem to be on equipment, with hump control, and with slow speed controls in them, for the really accurate low speed meter on them, I would suppose. Regards

Some of the CN SD40's have that particular speedo.

The U.P. uses pulse speedos on most of their equipment from old switchers and Dash 2s all the way up to the SD70s. Most of these are the type with the needle and dial rather than the LED lit style. They use an axle alternator with 20 ppr.

The needle looks best when pointed at 72 mph.