So I recently built this homemade pannel which is pretty basic but good enough for me. However I’m trying figure out a way to add coding somehow because continuous is annoying after awhile. Is there some sort of module I can buy with a code 3 option?
You could go with a System Sensor MDL3 sync module. If you put in the temporal jumper (circled below), it will output a temporal pattern rather than a sync protocol.
Nice panel build! I like the compact layout — looks clean.
If you’re trying to get away from constant tone and add something like Code-3, there are a few ways to go about it, depending on how deep you want to get into wiring or programming.
Since you asked about a module you can buy, here are a few commercial options that can handle coding or sync patterns:
- Wheelock SM/DSM modules – These are made for syncing Wheelock signals and do Code-3 out of the box. DSM is daisy-chainable for multiple circuits, SM is single-zone.
- Gentex AVSM – Works with Gentex devices and supports temporal coding (Code-3). You wire it inline between the NAC power source and the devices.
- System Sensor MDL or MDL3 – Sync module for System Sensor horns/strobes. Does Code-3 and syncs multiple devices cleanly, but only works with System Sensor products.
- Simplex 4905-9938 – This one’s a bit more niche, but if you’re running TrueAlert devices it gives you synced output with temporal patterns.
That said, commercial modules can be picky with brand compatibility and sometimes overpriced on eBay. If you’re already comfortable with DIY (sounds like you are), honestly your best bet might be a small microcontroller like an Arduino Nano or even a 555 timer circuit to generate Code-3 pulses through a relay. That way you’re not locked into any specific brand and can customize timing however you want.
Let me know what kind of signals you’re using (brand/model) and I can point you toward something that’ll work well.