• Get involved.
    We want your input!
    Apply for Membership and join the conversations about everything related to broadcasting.

    After we receive your registration, a moderator will review it. After your registration is approved, you will be permitted to post.
    If you use a disposable or false email address, your registration will be rejected.

    After your membership is approved, please take a minute to tell us a little bit about yourself.
    https://www.radiodiscussions.com/forums/introduce-yourself.1088/

    Thanks in advance and have fun!
    RadioDiscussions Administrators

Relay Closure Networking System...?

S

spinjector

Can anyone point me to a networked relay closure system of some kind?

I know the monster digital console systems like Telos Axia have networkable relay closures built-in, but in this facility we are years away from anything like that. I need something that can listen to relay closures on things like sat receivers, silence sesnors, and/or EAS decoders, and then distribute those signals to other places in the facility, such as studios, loggers, and BetaBrite/MBC-1.

I could develop something custom with a PIC microcontroller, and use the I2C networking capability, but well, that takes time, money, and headbanging. =-)

Thanks.
 
Barix.com. Look at annuncicom and application notes. Distributes closures over IP!
 
Thinking outside the box---touch-tone encoder/decoder. Gives you 12 different closures.

We bought a pair from Broadcast Tools for use on an STL hop (couldn't get satellite feed locally because of TI)--feeding the relay closures as touch-tones into sca on the stl channel.

Finally found the right contact and got the TI source turned off.; so the encoders/decoders went on the shelf.

Then I had a satellite receiver fail. Weekend, of course. Had another receiver with space for the functioning audio card and relay card (Starguides) but only one audio pair free between studios--not enough for 10 mechanical closures. So connected encoder to relay closures used the spare audio pair for the tones, and wired up the decoder to the trigger input leads on the automation computer.

Worked just fine.
 
Hi all, I just wanted to follow up with what I've found since my first post on this: nothing. Well, not nothing, but not what I was looking for, which is cheap and simple. Everything I found was exorbitantly - $100 to $300, and/or only had a few "channels" to work with. Some manufactures came close. There are devices such as the ADAM industrial control modules from Advantech, but I felt those are too expensive for what I want.

In the end, I decided that the only way to get what I need was to start hacking with microcontrollers, like "The Basic Stamp" from Parallax, Inc. But even these did not do what I want - the networking is where they failed to float my boat. I decided to ignore TCPIP from the getgo, as that involves wayyy too much technical overhead. I looked at 1-Wire, and I2C, but those didn't have the gazongas either. Then I started looking closely at CAN-Bus devices, and...bingo!!!

After doing much reading and comparing of low-level microcontroller-based communication networks, CAN-Bus is exactly what I've been looking for. It's a message based system, rather than address based, so all devices on the network hear all messages and act on them or ignore them, as they are programmed. It's differential half-duplex, and runs at either 400kbps or 1mbps. Microchip Corporation has nearly 100 different single-chip microcontrollers with CAN-Bus connectivity built in - for only a few dollars per chip. They also sell two chips, the MCP2515 CAN-Bus Protocol Controller, and the MCP2551 CAN-Bus Line Transceiver. The two are designed to work together and handle all the bus operations through the SPI interface of whatever microcontroller you choose, and provide both master, slave, and master/slave support - meaning they can both talk and listen.

All this being said, what I hope my end result will be is a network of relay closure detectors, with listeners that do "stuff" based on what they hear from the detectors. In their most basic form, the listeners would simply pass along a closure of their own to whatever equipment they are connected to. In more advanced forms, they could send serial messages to a BetaBrite, or control consoles, etc. In either case, each of the nodes would cost $10-$20. If I use an Mcu with a built-in CAN-Bus interface, it would be one 20-24 pin chip and a few passive support components. If I use the Mcu/controller/transceiver combo (preferred), it'd be three chips and a few extra components.

In the end, I don't know if I have the time/money/patience to develop this to fruition, but we'll see what happens.
 
I am intrigued by your reply, and I've spent the last few hours looking up info on CAN-bus myself. I have a need for the same thing you do: relay closures in remote locations. The CAN-bus system provides the means to put both relays AND switches at any place you have a node. You can even do analog monitoring of something if you like, such as a meter reading.

Having no experience with this system, I too am wary of what it would take to develop a multi-drop system. I also don't see you building a node for $10 or so, especially if you have to use real relays, and not just an open-collector port, and REALLY so if your time is worth anything. You have to have a circuit board to mount the three IC chips on, and interconnect them. Yes, you can do it on a project board, but that's a LOT of time and work, and when you take a hard look at it, those $200-$300 devices start to look pretty cheap! The people who build the commercially-available boxes have already done the hard work, and they're trying to make good on their investment.

In short, it would be fun for me to do as a hobby project, but I don't think my employer would like me to invest a lot of time in this--I've got FAR too much to do now. If I DO follow up, I'll let you know what I come up with. If YOU do, I'd appreciate the same.

Sincerely,

thebeaver32
 
can the Barix relay boxes be setup as a "relay extension?" Basically, can the barix boxes linked together over a LAN connection without a PC?
 
Yes.

cmac said:
can the Barix relay boxes be setup as a "relay extension?" Basically, can the barix boxes linked together over a LAN connection without a PC?
Click to expand...

Yes.

They can also be programmed to run macros (timed things like pattern changes, etc).
 
TomT said:
Thinking outside the box---touch-tone encoder/decoder. Gives you 12 different closures.
Click to expand...

16 actually....if you have the right boxes :) (Cant forget A B C & D...Also known as FO F I & P on the old military Autovon network)
 
Status
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.


Back
Top Bottom