CD&F Info and Reverse Engineering Progress!

[trevor229]

Hey everybody, I acquired a smaller yellow box CD&F not too long ago and decided to see if I could retune the receiver onboard for ham/amateur frequencies (Spoiler, I did it!). What that all led to was reverse engineering the entire thing. The article is still being updated by me as I discover new things, but I figured I would share it with you all to read. If anyone has any info on basically anything about the company or the controllers (models, history, manuals, diagrams, etc) please please do let me know via DM or something so I can document it! I found someone else selling the bigger grey controllers with buttons inside and the maxon data radios for not too much, I think I am going to grab one of those to look at as well.

I'm documenting things on the RECESSIM reverse engineering wiki, here's the link https://wiki.recessim.com/view/CD%26F_( ... ontroller)

[NahIDee]

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.

[trevor229]

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.

[NahIDee]

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.

[trevor229]

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.

Wow she is quite dirty in that pic! I do have some notes on the wiki about troubleshooting, I have fixed my tone filters by reflowing all solder joints with leaded solder. I've "broke" them and fixed them that way.

Unfortunately to precisely tune those filters you do need a scope and a tone generator. I think I could make a general graph of approximate set frequency to resistance of the onboard potentiometer. I'd want to get some more filters to try that on though just in case.

One side question, is there an FCC-ID on your CD&F anywhere? Perhaps on the radio board? I'm still trying to compile a list of models.

EDIT: I just went for one of the CD&Fs on ebay, I really hope I get a large silver one. I dont need or want another small one!