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Need Circuit Design -- Cheap...

I want to modify my X-10 Alarm system to trigger my camera's in my home and what I thought was going to be a pretty easy project turned out not so straight forward.

I am willing to pay a fair but moderate fee for a design that includes the parts list needed and a schematic, I can do the rest.

It turns out that the only place in the DS7000 (X-10 Security) that has any signial outside of the microcontroller it uses to indicate that it is armed is a LED.

The Voltage on the LED when the Alarm is Off = +5VDC (LED is off) The Voltage on the LED when the Alanm is On = +3VDC (LED is on) The voltage on the LED when the alarm has been triggered alternates between 3 and 5 +VDC as the LED flashes. (~100 times / minute fairly even, fast flash on/off)

So those are the three conditions I have to work with for this.

Here is what I need:

Conditions:

  1. When the LED comes on I need to Close a NO relay for about 1/4 second (SPST) and then the relay will need to open again and stay open. (The 3VDC will still be on)

  1. When the LED is Off I need to Close another NO relay for about 1/4 second (SPST) and then open again and stay that way until the LED comes back on. (The 5VDC will still be on)

  2. When the Alarm is trigered, Condition 1 will have happened, the LED will be On and have been on since I Armed the system, but once triggered, the same LED will start to Flash and will continue to flash until I reset it. When this happens the relay's don't need to do anything in fact, I don't want them to do anything, so basically this flashing condition needs to be ignored. Condition 3 will only happen when the systems is armed (Condition 1) and triggered.

The relay contacts will have less than 1.5 VDC at less that 10ma on them.

Constraints:

- Any parts must work from +5VDC (or less), Chips, Relays, etc.

- The sense current used to tap in to the LED should be very low, I have no idea how much current the LED driver from the microcontroller can deal with.

- The Flashing condition must be ignored.

- My preference is that the relays be solid state, but if mechanical is required that is ok.

- The parts should be as small as reasonable for me to be able to work with. I want to make this all fit in the X-10 DS-7000 case and there is some room in there but not a lot.

- No PIC's or other microtrollers used, I can do this with a PIC myself but I want to share this with some other X-10 hobbyists who don't have PIC experience or burners.

- This will not be a commercial product, I do not plan to sell it, you may retain any rights to it as long as I can share it for free for X-10 hobbyists only (You will be given credits of course). (If 10 are ever made that would be 8 more than I am aware of...)

Overview of what will actually be going on:

  1. I Arm my Alarm and the "On" relay will in essense push an ON button on an X-10 remote control PCB. This will power on the Camera through an X-10 Module.
  2. A motion detector in the area of the camera will trigger the camera to actually start to transmit images to an X-10 Device that will start a SanDisk recorder to record.
  3. After a set time with no motion all of this will stop.
  4. It must be assumed that the X-10 Alarm also get triggered during all of this since a security motion detector is covering the same area as the camera motion detector.
  5. After a set amount of time the X-10 Security System resets, but the "Armed" light stays blinking until I reset it, this is one way to know the system was triggered while I was not home.
  6. If the X-10 Security is triggered again before the reset, the LED still just blinks. (3-5 VDC)
  7. When I disarm the system the "Armed" LED will go out. (5VDC)
  8. The second relay (Off) will push the Off button on the remote PCB and power down the camera system.

I have everything to do this but the control relay circuit.

Please please reply to snipped-for-privacy@hotmail.com if you are interested in this project.

Thanks

Reply to
Bob Thomas
Loading thread data ...

Why hack into an existing unit?

Take a look at:

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Some additional desgin work will have to be done to set minimum 'on' time for the camera, blink ststus lights, etc.

--
Paul Hovnanian     mailto:Paul@Hovnanian.com
------------------------------------------------------------------
On a clear disk, you can seek forever.
Reply to
Paul Hovnanian P.E.

Hi Paul, Thanks for the link but the key to what I need is for the camera systems to only power up when the alarm system is Armed. I have X-10 Motion Detectors that will turn the camera's on and off, and set the recording on, and they are timed also.

The problem is two fold, the first is I don't want the camera's on all of the time, they have pan and tilt heads that would wear out after a year or so of constantly moving, I also don't want to be recording all of the them, the SanDisk recorder I am using only fits about 6 hours, and last, I don't want it recording me and my family just moving around in the house.

So the idea is to only have the cam system active when the Alarm System is Armed, which is only when no one is home.

Your idea is spot on for having the system always active, but I have that now, I also have a remote that I use to turn it on when I leave the house, but that means two remotes, one to arm the Alarm and one to turn on the Camera's, I want to automate it all off the Alarm System being armed.

Thanks, Bill

Reply to
Bob Thomas

Seems the specmanship is manager material. Are you sure that is the LED voltages?

Reply to
Martin Riddle

Not necessarily. Imagine a series R coming to a panel pin, and labeled "LED", LED from there to a grounding switch. Now... What do you see on that pin.... Hmmmmm ?:-)

...Jim Thompson

-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at

formatting link
| 1962 |

In Memoriam... Duane Lee Thompson October 31, 1972 - April 20,2006 4th Child, 2nd Son, of Jim & Naomi Thompson Victim of Colon Cancer

Reply to
Jim Thompson

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

Thanks, yea the LED drop + the Switch Vsat. Makes sense.

Cheers

Reply to
Martin Riddle

Very Sure, the way it looks is that +5DC is on a common line to all 8 LED's, then the other side leads to its own pin on a microcontroller, so you get about, what, a 1.7VDC drop from the LED taking it down to

3.7VDC and the 0.7VDC could be the switch in the micontroller or some from that and some from a current limiting resister.

Now all I need so someone that can "help me" design what I need for a reasonable price. 25 years ago this would have been at best a 2 day project, maybe 2 hours, but your manager comment was kind of funny, I when in to management 25 years ago (frontal lobotomy required) ans have really lost my touch. I do about a project ever year or so using PIC's so it removed me even further from what would seem to be a simple descret component project...

Reply to
Bob Thomas

That is likely it, there are 8 LED in the series of LED's, one side is all on a common line @ 5VDC, the other side leads to a microcontroller pin for each LED, not sure of the R is on the commmon 5VDC rail, or each LED has one between it and the microcontroller, or the rest of the drop is from microcontroller itself.

Still my issue remains the same, finding someone to "help me" design a circuit to do what I described in my first post, my hands on knowledge could be called rusty at best.

Any suggestions?

Reply to
Bob Thomas

"Voltage on the LED" means measured where?

...Jim Thompson

--
| James E.Thompson, P.E.                           |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |

                          In Memoriam...
                       Duane Lee Thompson
                October 31, 1972 - April 20,2006
          4th Child, 2nd Son, of Jim & Naomi Thompson
                     Victim of Colon Cancer
Reply to
Jim Thompson

So, is it driving a 7-segment LED? What is the digit output for different conditions?

It will not be cheap, if you insist on solving digital problem with analog solution.

Use =B5C.

Reply to
linnix

They a 8 separate LED's, one just happens to indicate that the system is armed, they are individual. I may end up and just use a PIC in the long run, it did not seem that hard of a problem.

Reply to
Bob Thomas

If I measure between the circuit ground and each pin of the LED when the LED is OFF I get 5VDC on both pins, and when the LED is on I get

+5VDC on one pin of the LED and +3VDC on the other pin.

If I measure across the two LED pins directly, with the LED ON I get

1.9VDC, when the LED is OFF 1.2mV. (almost 0V)

When the LED is Flashing I get alternating readings between roughly 0V and 3VDC wnen measuring across the 2 LED pins.

When measured between the LED and circuit ground I get 3VDC and near 0 VDC alternating on one pin, and the other is a steady 5VDC when flashing.

I was kind of hoping that a cap or something could be used to smooth out the flashing and have that looked at by the control circuit I am looking for as the same as the LED being ON.

It seemed to me the biggest issue was telling when the system was armed or not, if it was not for the flashing when triggered it think that would not have been hard. The rest is just trigging one of 2 relays for a short time one for each state armed/disarmed.

Thanks...

Reply to
Bob Thomas

ff)

on)

=A0 =A0 =A0...Jim Thompson

=A0 =A0...Jim Thompson

Sound like there are pull down resistors from the controller pins to LEDs. Just cut the LEDs and hook the port pins to your own =B5C. You can mirror the LEDs with other output pins of your =B5C.

Monitor/count them from your =B5C.

Reply to
linnix 

--
This should work: (View in Courier)

.       +5V
.        |
.        +---+---+---------+------+----------+-[+10µF-]-GND
.        |   |   |         |      |K         |8     
.      [10K] |  [Rt]     [10K][1N4148]   +---+---+
.        |   |   |         |      |     2|_ Vcc  |3
.        |U1A|   +-[100nF]-+------+-----O|T   OUT|---+-----+
. VARM>--|--|+\\  |                      6|       |   |     |K
.        |  |  >-+         +5--[1M]--+---|TH 7555|[COIL][1N4001]
.        +--|-/  |                   |  7|_      |   |     |
.        |   |   |                   +--O|D      |  GND   GND
.        |  GND  |                   |   +---+---+    
.        |       |                [200nF]    |1        
.        |       |                   |      GND 
.        |       |                  GND
.        |       |
.        |       |        +5
.        |       |        |
.        |       |        +---------+-----+----------+-[+10µF-]-GND
.        |       | LM393  |         |     |K         |8
.        |       |  U1B [10K]     [10K][1N4148   +---+---+
.        |       +--|-\\   |         |     |     2|_ Vcc  |3
.        |       |  |  >--+-[100nF]-+-----+-----O|T   OUT|---+-----+
.        +-------|--|+/                         6|       |   |     |K
.        |       |                +5--[1M]---+---|TH 7555|[COIL][1N4001]
.      [39K]    [Ct]                         |  7|_      |   |     |
.        |       |                           +--O|D GND  |  GND   GND
.       GND     GND                          |   +---+---+    
.                                         [200nF]    |1       
.                                            |      GND         
.                                           GND

 

The values of Rt and Ct will depend on the flash rate of the LED, so
post the rate and I\'ll post the values.

Relays are Hamlin HE721A0500.

Send the check to:

John Fields
8905 Bluegrass Drive
Austin, Texas 78759

JF
Reply to
John Fields 

--
Oops,  hold the check...

JF
Reply to
John Fields

Hi John, OK, holding check, but about to order the parts, I just have one question regarding U1 the LM393, here is the pin out I found on Digi-Key, can you tell me the pin-outs I would use from your schematic?

I added my best guess to your drawing at the bottom, can you see if that is right?

------------- Output A | | V+ -------|1 8|------- Inverting Input A| |Output B -------|2 7|------- Non-Inverting Input A| |Inverting Input B -------|3 6|------- Ground | |Non-Inverting Input B -------|4 5|------- | | -------------

Here us the URL of the LM393 I used for reference:

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Why hold the check? Is there something wrong you discovered since posting? As for the flash rate I will try to get a better count, I did it by just trying to count and time at the same time but I will put my Freq counter on it and see if I can get it down pat. I counted about

50 flashes in 30 seconds, so 100 flashes per minute, ~100Hz?

I plan to order the parts ASAP and try and test it by this or next weekend at the latest, so if I should old on that please tell me now.

Thanks,

Again, you can email me at snipped-for-privacy@hotmail.com if you want to send non-ASCII schematic with the pinouts.

I added the pin numbers for the LM393 as I "guessed" them, could you please review and correct as needed?

Thanks, Bill

Reply to
Bob Thomas

LM393 can't compare to +4V with a +5V supply ;-)

...Jim Thompson

--
| James E.Thompson, P.E.                           |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
 I love to cook with wine     Sometimes I even put it in the food
Reply to
Jim Thompson

ave

rting Input B

/ds/LM/LM193.pdf

That's a little more than 1Hz, of the order of a few Ohm-Farad. Save your check for huge resistors or caps.

Reply to
linnix 

--
Aarghhh... you\'re right, you sly devil... ;)

In all candor, though, if I had to have someone review my designs who
could do so with accuracy, authority, and without rancor, I\'d probably
choose you.  

Except where external hysteresis-free comparator based VCOs are
concerned, of course ;)

JF
Reply to
John Fields

Thanks! I appreciate that!

Huh? Can you cite one that didn't have hysteresis? I may have erred, but I doubt that I did. Was I too subtle ?:-)

While working on a "real" project, during waits for simulation results, I've been pondering the OP's requirements... not very clear as to sequencing. A good if-then sequential description would help.

...Jim Thompson

--
| James E.Thompson, P.E.                           |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
 I love to cook with wine     Sometimes I even put it in the food
Reply to
Jim Thompson

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