These do use piezos as I heard the one in my aunt’s house many times since it was in the kitchen. It did 4/6 and according to the box it was made by Gateway Scientific so odds are it has the squared back and metal mounting braket like my 1980’s Sears (never saw my aunt’s off the ceiling, I’ll find out once mine arrives).
Cool. You will have to make a video of it too. Those black boxes on the mounting base do look kind of odd. Were there smoke alarms like these had had squealers at one point? I could be wrong and as probably thinking of the older first alerts (the sa76rs) and I think there was one other first alert that had a squealer but I forget that model. Never realized how many different ones there were.
Time signature has no impact on the speed, or tempo, Time signatures are simply fractions, with the top number representing the number of beats in a measure and the bottom indicating the value of a beat (2=half note, 4=quarter note, 8=eighth note, etc). To give you an idea, standard code 3 is in 4/4 (4 beats/round, with 3 “notes” and 1 beat of rest) at a speed of 60 beats/minute. March time is so named because “standard march time” is at a speed of 120 beats/minute, which is the typical tempo of a standard march, such as those written by Sousa.
That being said, a continuous beeping would be 4/4 or 8/8. Stuff like California code or 4-4 would have the funky time signature.
Oh okay thanks for explaining that to me. Very interesting. 
Nice, I’ve been thinking of adding one of those to my collection. BTW love my PA400+PS24LO 
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I found a wiring harness and mounting bracket for the 710CS on eBay. It came in yesterday’s mail so after I got home from work this morning (6:30am), I wired it, powered the smoke up, and turned the knob to test. Instantly it went into alarm (does the typical Gentex smoke trill), and after a second or 2 delay the strobe flashed, and continued to do so for another 2 seconds or so after turning the knob to normal. Forgot how loud those Gentex smoke were, yet oddly my wife slept through it (I’m going to install a smoke in our bedroom). I plan on shooting a video of it tomorrow.
Great to hear, i’m glad to have you as a valued customer!
Here’s a Kidde KSA 300. It resembles a Probe, except for the bottom design:
http://www.ebay.com/itm/Kidde-KSA-300-22644-Smoke-Alarm-w-Intensity-Safety-Light-NEW-NIB/381622880578?_trksid=p2045573.c100033.m2042&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20131017132637%26meid%3D3112b8a90e8e48bbafa11d25772cafa3%26pid%3D100033%26rk%3D1%26rkt%3D3%26sd%3D381622880578
That Kidde also looks a bit like on old Sears too. Does that Kidde have a piezo or squealer horn?
The Smokey Stover 4002 came in on Wednesday. Why they chose Smokey Stover which had been out of print since 1973 instead any of the other Sunday comics characters around at the time (I know Snoopy was already being used by Jameson) I have no clue. This smoke was made in 1985.
Piezo. The ones in my Sears are black.
The box, one of more unique ones out there.
Here’s a test, this one has the same pitch as the Sears in my grandparents house did (the Smokey Stover in my aunt’s sounded a 1/2 step higher)
I also shot a video of the Gentex 710CS
Cool Smokey Stover unit. I still could have sworn there was a unit that looked like this but had a squealer and if there was a post about that im sorry for repeating myself. LOL!!!
Neat! That’s been on eBay for a while, glad someone finally got it. And I hadn’t known that it actually is made by Gateway (hence the square base) which is probably why the Sears sounded like it (since it was also a Gateway rebrand). There’s a video on YouTube of the hardwired version (can’t remember who posted it)
Does the hardwire version also have a piezo? I was unable to fine the video on youtube.
Yes, it does have a piezo.
Oh okay thanks for posting that video.
Found these @ Savers in Rochester.
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The one on the left looks like your typical 4120, (and so I thought) but when I looked at the back…
It’s actually a Family Gard FG140! I didn’t even realize they were making hardwired units up to 2005. I thought they had switched back to just battery models after their run of the 1839WN-style units.
Sadly when I opened the RS’ box, the base was broken! Evidently the previous owner got mad and slammed it against something. It still works (4/6) but the cover doesn’t like to stay in place, it keeps rotating even though the screw is tightened all the way.
It’s been a while but I found another rare one: a NiB 8201-401C with something special.
Notice it yet?
No? ok lets take a look under the cover
it also sounds higher pitched than the others I’ve come across but still does the GE warble
All 3 of my smaller Home Sentrys
all 3 with the covers open
I believe all I’ll need is the line cord square 8201 and I’ll have the entire Home Sentry line.
Here’s one I found at our flea market that comes every year at this time. It’s a Sears ⁹57474.
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Look at how yellowed the clamshell package got! I’ve seen this before on other alarm clamshell packages.
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Side by side with my ⁹57470.
Nice alarms. Those Sears units look rare as well. They both have piezos right? The sears unit on the left look a bit like my Nortron unit only the Sears unit is smaller. Never saw them growing up but still neat units.
Here’s a GE Home Sentry 8201-401C on ebay, but with a twist that I’ve only seen once before…
http://m.ebay.com/itm/1975-Vintage-Smoke-Alarm-General-Electric-Home-Sentry-GE-8201-001-/122011147680?nav=SEARCH