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Digitrax SW1 SDF: SW1: SW1 #4742 Diesel Scheme Copyright (c) Digitrax Inc. July 8th 2007

(C) General Notes

This sound recording courtesy of Eureka Springs and North Arkansas Railway Company, Scenic/Heritage railroad, and very helpful Engineer Tom LeClair. Visit arranged by Loy Spurlock. All sounds recorded by AJ Ireland at Eureka Springs AR, June 22nd 2007.

Note: This SW1 prime mover has significant low-frequency components at idle and low notch settings, so the speaker enclosures should be as large as possible behind the diaphragm to extend adequate frequency response below e.g. 300Hz. This will ensure a more "full" sound that does not appear thin or "tinny".

Each engine we have recorded has a distinct 'personality', so a particular locomotive example may sound slightly different due to unique e.g. tappet, crank-rate shell vibrations and exhaust-stack differences. Horns and bells are often moved between locomotives, and some roads may change/upgrade prime-movers, or change a normally aspirated engine with turbo-chargers etc.

This 600HP SW1 thottle does not strictly "notch", but this scheme employs a notched arrangement for consistency with other schemes

For CV155=01 ["Semi_automatic Notching"], the Prime mover lowest Notch setting is set by the throttle speed setting. F6 (ON) can increase the Notch and F7 (ON) will decrease the Prime mover to the minimum notch set by current throttle setting. If you leave F5 on, you can wind the engine handbrake forever!!