« Some Number Stuff - John Dunn, Consultant, Ambertec, P.E., P.C. | Main | Root Mean Square versus Root Sum Square - John Dunn, Consultant, Ambertec, P.E., P.C. »

February 04, 2012



Thanks for the tip. I will definately use that in some of my (bad) music composition.

Stoney McMurray

Try augmenting the Bb to Bb# -- OK: B, which is more classic train-whistle. But why do the Canadians specify the key? It would be interesting to know whether this was based on some study of human perception of train whistles, or just some arbitrary bit of bureaucratic over-reach. Certainly, the augmented triad is meant to be more jarring than a plain minor triad would be, and thus more attention-getting for anybody with an ear trained even minimally to Western music.

William Ketel

The whistles that we made in the shop to simulate a train whistle, which they did fairly well, used tubes that were 4,5,6,and 7 inches long. With the plugs taking up about 1 inch total, it was an interesting way to provide uniformity without needing any complex instrumentation. And they all did sound pretty much the same. It was a good use for scraps of hydraulic tubing.

John Dunn

From the group Technology Professionals of New York and New Jersey:

C.K. Leverett, PMP • John, I sent your link off to a group of railroad friends, including a couple of Canadians, and got this response back from one of them:

"The reason Canadian horns must be three tone goes back to the initial introduction of the EMD F-units in the 40's. The single tone (blat) horn was close to a moose mating call, and attracted them to the tracks where many were killed by trains."

So now we know the rest of the story.


Thank you, C.K. Leverett.

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Your comment could not be posted. Error type:
Your comment has been saved. Comments are moderated and will not appear until approved by the author. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.


Post a comment

Comments are moderated, and will not appear until the author has approved them.

Your Information

(Name and email address are required. Email address will not be displayed with the comment.)


  Learn about our  

 free engineering 

consulting referral 

      service at:


  IEEE Consultant's 

      Network of 

     Long Island


We have over forty 

electrical, electronic, 

mechanical and 

software engineers 

with expertise in more 

than sixty-five categories 

of technology and business. 

All are members of the 

IEEE and adhere to the 

IEEE professional codes 

of ethics. 

No fee is charged for the

referral service. 

Each member is an 

independent consultant 

and negotiates his/her 

own consulting agreement.


Editor: Jerry Brown


John Dunn

Marty Kanner

Murray Kleiner

Dick LaRosa

David Pinkowitz

Carl Schwab

Gerry Bodner

Larry Rachman


Unless otherwise noted, 

reprinting or republication 

of anarticle on this blog is 

authorized by crediting the 

author and prominently 

displaying the following 

sentence at the beginning 

or end of the article,

including the hyperlink to

IEEE Consultant's Network 

of Long Island

"This report is republished 

with permission of IEEE 

Consultant's Network of 

Long Island"



Blog powered by Typepad

Enter your email address:

Delivered by FeedBurner