trevor229 wrote: ↑Wed May 01, 2024 10:00 pm
NahIDee wrote: ↑Sun Apr 28, 2024 4:12 pm
I've been waiting for someone to do something like this! Best of luck on it! I've got a large CD&F if you're interested in tackling that.
I've got a 1991 Plectron / Federal Signal SC controller I'm trying to get working; I might be interested in some help with reverse engineering the tone filters since they're all missing.
Oh nice! Is it like this one I saw on ebay? I tried contacting the guy to ask for a large one and offer to pay extra to ensure that/for the hassle but no response. The ones with maxon radios seem luke a much better solution, there were some earlier variants of this kinda that are all analog in the radio board. Looks like that entire board is modular as well. Needless to say, if it is like this one I am definitely interested! I'd love to see pictures if you have time.
It's currently a WIP on getting it working right now. The receiver is a D.L. Johnson EF-3410 UHF receiver, instead of the later Maxon radios. I wasn't able to get it, but I found out how to bypass the audio output from the radio to the audio input to the tone filters. It was originally wired for 230VAC instead of 115VAC, so I took the time to do the work on getting it switched to 115VAC. I encountered a few issues with the fire signal card randomly activating, and also the power supply module having a solder joint on the unregulated 18VDC pin cracking and causing a loss of power across the board.
Of the five tone filters that came with the board, only two of them work. I've got three NOS XR2211CPs coming within the week or next week to see if that'll fix the issue.
With the Plectron RCS / Federal Signal SC, the previous owner deliberately cut one of the oscillator crystals off and tossed all the tone filters. Luckily, I have both the Federal Signal manual and the Plectron manual for the board, and have the schematics to make new tone filters if need be; problem is, I don't have the oscilloscope or RF generator that's needed to program the tone filters. I got a replacement crystal on hand, just I have yet to install it.
Here's a picture of the CD&F after I originally picked it up. The enclosure now houses a Federal Signal FCH and is mounted on the backboard for an Alertronic panel.