Horn and photo courtesy Brent Lee.
The S-3K is generally similar in appearance to the S-3L, and the same prefixes and suffixes apply to its designation. The horn was introduced to comply with a Canadian Board of Transport Ministers regulation requiring the use of the D# minor chord on railroad airhorns. Ironically, few were sold in Canada, but a number appeared in the US, particularly on early GE locomotives.
Prime Manufacturing Corp. of Oak Creek, WI produced a horn identical to the S-3K, which they called the PM-990.
Factory tuning: 311, 370, and 380 Hz (approximately D#, F#, A#)
No large railroads have acquired the S-3K in recent years, but a few can
still be heard on older BNSF locomotives of Burlington Northern ancestry.
S-3K sound samples:Burlington Northern, various locomotives:
Sample 1...355kB...16 seconds
Sample 2...85kB...3 seconds
Sample 3...134kB...6 seconds
Sample 4...117kB...5 seconds
Sample 5...180kB...8 seconds
Sample 6...436kB...20 seconds
Sample 7...259kB...11 seconds
Sample 8...161kB...7 seconds
Sample 9...377kB...17 seconds
When bad things happen to good horns:Like its more common cousin the S-3L, the S-3K shares the Supertyfon family propensity for harmonic overblowing and generally getting into trouble. Below are a few examples of S-3K's with various problems on Burlington Northern locomotives.