Unitrol 480K?

[q2bman]

Ya the horn, to me, sounds not at all like a horn. I don't know what horn they were attempting to mimick. The pa 300 is the best "air horn" sound. It doesn't sound like a horn but at least it is as loud at the other tones. The whelen horn sounds like some highschool b-ball game just ended. More of a buzzer than a horn. I wounder why no one has ever came up with a harmonic dual tone wail. That would seem to be very effective. It's not the cold war era any longer, why do we not use dual tone sirens? They are very effective.

I would like to see Whelen come out with a dual tone siren that has the wail feature time so that one output is slightly less frequency wise than the other output. Kind of make a harmonic siren tone.

Can you imagine a dual tone Thunderbolt flying down the street!!!

Hows that for bothersome!

[Robert Gift]

I'd love that, but it wouldisturb the peace too much.
(I'm looking forward to hearing a Thunderbolthis Wednesday during Denver's 11 a.m. monthy test.)

In the late 50's a new pumper arrived at my father's station (Peeble's Volunteer FD) whichad two sirens.
They came as a matched set, sounding a minor third or a 5th apart - as I recall. Each had a red light on the front of it.

Sounded very desperate, as though crying - wailing.

I think the dissonant sirens would stand out even better.
Didn't someone make a dissonant hi-lo?
Like AB "Hi" and FG "Low"?