Synchronized Clock/PA/Bell System Enthusiasts?

Hi all,

I was just wondering if anyone is aware of a similar forum or Discord server that focuses on systems of synchronized clocks, PA Systems, Bell systems, etc. Mainly since I have a few questions for enthusiasts of such systems but would also love to learn more about them. Thanks!

I don’t particularly have an answer, however I think there were a lot of enthusiasts in this community that overlap. Hoping that someone here can help you out! What kind of questions do you have?

I’m trying to figure out my school’s clock/PA/bell equipment and how they all tie in. My school has multiple buildings of various ages and with that comes a variety of systems used. Here are some of the questions I had:

  1. Master Clocks. What could my school’s master clock situation be? One building, we will call it Building A, the older building that I’d expect to host the clock and PA systems, uses Simplex 6310 synchronized clocks, and a master clock in a locked utility closet, so I can’t see it. This particular closet is right next to my locker and did happen to be cracked open the other day as there were some Wi-Fi issues IT was working out, but I didn’t think to peek inside. The other two newer buildings (let’s call them B and C) use wireless Sapling clocks that I have noticed are about 15 seconds ahead of the clocks in Building A and are synced exactly to Apple/Internet time, meaning the clocks in Building A are around 15 secs behind. Does this mean there are two different master clocks? What kinds could they possibly be based on the visible hardware?

  2. Privacy/Call Switch? Another thing I have noticed in my school is these Simplex switches (only in Building A) that I cannot find a model number for. They basically look like little black light switches on metal panels, the top saying “PRIVACY” in little letters. What are these used for?

  3. Perhaps the Most Confusing: The Bell System! Lastly, I am trying to figure out what kind of bell system my school uses. My school bell sounds like this (volume warning) and produces about a 2 second continuous tone like that to signal class changes. This tone sounds in all 3 buildings, but it sounds the clearest in Building A if that makes sense. Buildings B and C, assuming they were built AFTER the installation of this system, likely get bell/PA feeds wirelessly since the bell and announcements sound a little distorted. (side note: if anyone knows the equipment they use for THAT, I’d love to know, but it’s not as much of a mystery as the rest of this.) I am almost certain that the bell/PA system is Bogen because the speakers all around the school are Bogen. I know that Bogen PA systems have a “time tones” feature I read a little bit about where they can be connected to a relay of a synchronized clock system or something along the lines of that, and play a tone when the synced clocks hit a selected time. Based on all of the above information, does that seem likely? Based on the tone sound I provided, would any enthusiasts be able to identify any particular equipment?

Next week I will look out for any other “clues” and reply to this topic with them. Thanks to anyone who knows anything!

Maybe in places like a nurse’s office where you don’t need a bell to go off at the end of class, you can turn it off for that room. Idk much about PA systems, so don’t quote me on this

They most likely disable the microphone in the paging speaker or something, because depending on the system the admin may be able to listen in on rooms, and that switch inhibits that function for that room.

Yeah, seems very likely. I’m just curious about why it’s Simplex because to my knowledge they don’t make bell systems.

They may have at one point. Their original name was Simplex Time Recorder.

Simplex used to be big in the time industry. My school had a Simplex mechanical class change bell system until it died a few years ago.