I've been thinking of trying to make a coin operated tv to limit its use by the kids, or at least compell us to think about how much tv we watch. I've got full spousal backing on this, so it occured to me that I could use an x10 controller hooked up to our pc to do this, with some sort of script that would let us put "time" in someone's tv account, etc.
Just wondering if anyone has done this, or something like it, and if the minimal startup costs would be less than the cost of an off-the-shelf coinbox, about $80.
Thanks very much. We have an existing pc that stays on all the time, mostly because after upgrading to XP it won't turn off from within windows. I will check out retrobox, this all sounds very do-able!
I built something similar to limit telephone usage on school nights. A callerID device from Rochelle with an RS232 serial port was connected to one of my PCs. A serial port connected relay board was wired to the phone circuit. While the Rochelle board reported the line "off hook" a timer would increment. 2 minutes prior to cut-off there was a double-click on the phone line. Then the phone would go dead until the next morning.
You can do pretty much the same thing. Wire a relay to short the video or CATV input to the TV set after x-number of minutes hours. If you've got a PC-based HA system or at least have one PC that runs all the time it's fairly easy to do. A simple push-button can be wired to an I/O device. The kids would have to press the button to get the TV signal. This will trigger the timer. The software I wrote for the purpose was simple enough but it was written in THEOS BASIC which is neither PC nor Linux compatible so you'll have to write your own version.
A somewhat less elegant but much simpler solution is to install a programmable timer. ELK Products and Altronix both make devices which can do the job. I sell both of these brands online in case you're interested. The URL is in my sig.
I personally would just give each kid an X10 compatible device (keychain remote, security "panic" button, etc. depending on what hardware you have available) and use that as their unique token. When they turn the TV on with their token, a timer that deducts from their "allotment" is triggered. When they shut it off with their token, the deductions stop. If they turn it off without the token, the timer keeps running and kills the power to the TV (thus enforcing the fact that you need to use your token to start and stop watching).
None of the tokens should be set to directly turn the TV on or off. Rather, they should be using unused RF or X10 codes which a home automation PC can then use as the timer trigger. This requires a setup like Misterhouse or one of the other software packages, which is how all of my stuff is controlled anyway. The trigger (assuming Misterhouse) can read in how much time that token has allotted, start the timer with that amount and keep counting down until it has received an "off" event from that token.
Personally, I'd go the RF remote route as it's easier to detect uniquely without using up X10 addresses. Additionally, using X10 outlets instead of appliance modules will let you completely kill the power to the TV (and whole room if you replace all of the outlets). Much of the implementation details will center around how draconian you need to be, where the TV's will be, etc. For instance, if the timer kills the TV through an appliance module and the kids just unplug the module and plug the TV into the wall ...
is that likely?
if it happens, is it a big deal?
If both are true (as opposed to just wanting to mildly enforce family rules that get forgotten as the hours in front of the TV roll by or implementing something similar in a commercial context), your implementation will be much more difficult and will probably require locking the wall plug and the X10 outlet together somehow.
This all operates on a principle similar to how most folks use the motion sensors for lights. Motion triggers the lights on and a timer that either counts down until it expires or is renewed by further motion.
The X10 wall outlet will run $15-25 or so.
You didn't mention whether you already have an X10 software/computer setup. If not, that will add to the cost, but neither as much as you think or will it not be usable for future projects. My current home automation box came from retrobox.com for $60 and I threw an old Win2K license on it.
J Wynia Myriad > I've been thinking of trying to make a coin operated tv to limit its
Probably a better way to do this is with HomeSeer software. There is a module that allows you to schedule an allowance for using certain devices. Here's what it says in the HomeSeer manual:
"HomeSeer has the ability to track the use of any device connected to an X10 controller. If you would like limit access to the television or a video game console, you can create accounts for family members and give them a fixed amount of time to use the device. For example, you can give Bill 1 hour a day to play video games and give Sue 6 hours a week to watch TV. When the user uses up his/here time, HomeSeer will turn off the device. It is very inexpensive to setup and uses a single X10 appliance controller and a 4-button tabletop controller. "
As much as I hate to say this (mainly because I'm likely not much older than the group being targeted and many of my income-earning interests come from stuff I originally learned about on TLC/Discovery/History/CourtTV/National Geo/... And I don't know where I would be now otherwise, but:
Tip I've learned from trial and error at my day job (Classroom Media/Video Conferencing/General A/V Engineering & Design for a 8,000 student university): Find one of the better quality outdoor receptical "Weatherproof in-use" covers (the "bubble" kind with slots at the bottom for the power cords to exit) and screw it over the (in this case) X10 outlet.
Most of these have a loop for a (small -- luggage-type) lock of some kind, and those that don't can be modified in a fairly trivial manner to be secure enough. We do this in classrooms where the electrical outlet used by the Instructor's equipment (computer, DVD player, etc) is accessable to discourage people from stealing our power and 'forgetting' to plug things back in for the next class.
See, for example:
formatting link
If you do this (especially with one of the metal covers) it will be virtually impossible for them to physically bypass your controls without destroying something (power cord, outlet, outlet cover) along the way... Unless they find an extra X10 transmitter.
There's not much that can't be done with off the shelf hardware and a bit of elbow grease. Particularly with free/open source stuff like MisterHouse. I've looked at HomeSeer as well and, while it's got some realy nice features, ~$160 as the price tag just for the software is a little steep given what that will buy in hardware.
My home automation PC setup:
Computer - Celeron 800, 256MB and 20GB hard drive: $65 from Retrobox.com OS - Unused Win2K license (MH also runs on Linux which is free) Monitor - Unneeded after initial setup using UltraVNC
formatting link
to remote control the PC. Serial connector to X10 wiring (CM11A) - Included as part of the $50 "ActiveHome" kit from Automated Outlet
formatting link
A W800 RF antenna/reciever for grabbing security remote, keychain remote, etc. RF transmissions straight to the PC. This was $75, but would have been $60 if I'd opted to go without the larger antenna.
formatting link
All of the above adds up to about $190 and, short of the actual sensors, outlet modules, keychain remotes, lamp modules, etc. is everything you need to take complete control of X10 on a dedicated PC.
This machine sits tucked into my office closet happily monitoring activity in the house through the motion sensors and door sensors, controlling lighting, sending me reminders (to shut the windows when rain is forecast, etc.) and doing other routine tasks.
Putting the PC in the middle means that even though I just hit the switch to kill the lights in my theater and that switch just sends an "A2 OFF" X10 signal, the lights actually ramp slowly down over 3 minutes, signaling the start of the movie (while still giving me time to see the remotes for subtitle setup, etc). Hitting it twice in succession kills them immediately. This whole setup lets the X10 devices be simple/dumb and putting the intelligence into a machine built to do the complicated decisions.
J Wynia Myriad Intellect, Inc. "Web technology that earns its keep."
That is a genuine concern, but not insurmountable. I've built software systems and hardware setups that had "tamper-proof" as part of their design. For any kid where a "quick backhander" would be adequate, a system can easily be built to both prevent tampering as well as alert you to tampering.
I've heard these same arguments for keeping kids off the wrong sites on the Internet and monitoring when something gets through and that problem's solvable as well. I know because I've set successful systems into place for this problem where people had been told over and over again that the kids were just too smart and would certainly get around it. When they described the proposed solutions, it was clear why they said the kids would get around them. Their solutions were amateur at best and demonstrated a clear lack of imagination and proper planning for the inevitable attempts.
For any project where this may be a problem, you need to gauge the severity of the problem and apply the appropriate amount of planning. I'd definitely plan entirely differently for limiting TV watching or computer use in a common family room than for in a kid's bedroom. I'd plan entirely differently for kids who have a history of circumventing the rules than for kids who just lose track of time and need a reminder.
In this instance, there are several control points and circumventions that a kid has the skills to pull off. The TV needs power (which is why X10 is a logical choice). If you have both logging of power sent to the TV and when it is turned on and off, you have a control point. The probable circumvention is to plug the TV into a non-controlled electrical outlet. If that's likely, you should plan for that. Either using one of the outdoor locked outlet boxes mentioned earlier or in some other way, make sure that anywhere that the 125 pound TV can be moved by the child has a controlled outlet. At that point, the only circumvention method is cutting the TV cord and splicing a new end on it. While not beyond some older children, you're quickly reaching a point of absurdity for the typical family's children. However, even this can be dealt with by keeping the TV itself locked in a box. And, if channel selection needs to be controlled and can't be directly through cable or satellite box, removing access to the IR sensor for the original remote, instead using an IR relay through the computer, etc. In short, somewhere along the process from wide open access to prison-level TV lockdown there's a solution that will prevent what you want prevented and won't be circumvented without you knowing it. And, oftentimes, just knowing that it's been circumvented is exactly what parents want in the first place.
They want to limit the TV to x hours per week, but aren't able to easily track it themselves. This solution will work FAR better than some chart on the refrigerator and the honor system.
Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.