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LED flasher does not work need help.

JonSea

Well-Known Member
Most Helpful Member
Yes, individual LEDs are still made and sold (Snarky comment will remain in my head only).

Try searching for "5mm LED"

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gary350

Well-Known Member
I guess it won't hurt to use other color lights thieves are typically stupid they will probably think blue or green is a different type security camera. LOL I was originally thinking of using all RED but it is probably better to use other colors too. 150 LED lights maybe I can put 5 LEDs in parallel to get brighter lights easier to see after dark.

More LEDs have been ordered.
 

JonSea

Well-Known Member
Most Helpful Member
Geez oh grief. Sorry I was specific enough. If you want RED LEDs, search for

"Red led 5mm"

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audioguru

Well-Known Member
Most Helpful Member
Do you live in a tent in a park? Then you need batteries for your blinking lights because there is no electricity outlets in the park?
I live in a brick house with locked doors. I do not need blinking lights because thieves do not come here.
 

shortbus=

Well-Known Member
Law changed about 10 years ago we have the right to protect our self if someone is sneaking around in the dark and I shoot them dead it is not a problem 1 less thieve for the legal system to deal with.
I'd run that by a lawyer before trying it out. You can't even do that in Florida. Shooting someone just for trespassing is not the same as "standing your ground".
 

JonSea

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Most Helpful Member
Shoot first and ask questions later - like why you shot and killed the neighbor's dog or worse their little kid who was playing hide and seek.

If someone is kicking down your door and your life is threatened, shooting someone is justified. If your LIFE is not threatened, murder cannot be justified.
 

gary350

Well-Known Member
Do you live in a tent in a park? Then you need batteries for your blinking lights because there is no electricity outlets in the park?
I live in a brick house with locked doors. I do not need blinking lights because thieves do not come here.
YOU must have low crime where you live. Locked doors keep out good people not thieves. Crime keeps getting worse apartments near the house we use to live police were there several times every night. There were shootings there all the time. Lots of houses were getting broken into so we moved to a better neighbor hood. We lived in a better neighbor hood until children graduated from college sold the big house and down sized to a smaller house in a nice neighbor hood but now houses are getting broken into almost every night here. Kids come around after dark break out car windows to see what they can steal. People 2 houses away were broken into and beaten with baseball bats they were in the hospital 2 weeks, police arrested the 2 boys that beat them they spent 30 days in jail now they are out on porbation. People across the street were broken into and several houses near us broken into and 2 cars were stolen. Crime gets worse all the time minimum wage has been $7.35 for 17 years no one can live on that. Drugs get worse people steal to buy drugs. So far people with barking dogs have not been broken into. Some towns crime is worse than others. I caught a girl in my vehicle in Walmart parking lot few weeks before Christmas she was searching the glove box when I opened the door, she jumped out and ran. Our dog is old it is a good watch dog barks at everyone she sees. I would hate to shoot anyone.
 

JonSea

Well-Known Member
Most Helpful Member
Maybe instead of dozens of randomly flashing LEDs, Gary should address the problem more actively.

These cheap microwave radar sensor modules could be used to switch on an LED when a person is detected. These modules have a wide, non-directional detection range, and are designed to stay on for a minute or two when motion is detected.

They operate from 4.5 volts, with a quiescent current of 3mA, with an output that will provide up to 100mA at 3-point-something volts which will be adequate for a red LED (current limiting resistor required). This is probably the most practical solution in this monumental thread and actually addresses the problem it's meant to solve.

I've played with these modules. They will detect a person through a sheetrock wall with no problem. I did a few tests to see if I could limit the field of detection without any luck. Even in a tall narrow steel can with one end open, detection was omnidirectional.

Note the price shown is for 5 boards. They are less than a buck a piece.

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JonSea

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Most Helpful Member
AA alkaline batteries are rated at about 2500 mAh, which would provide over a month's operation.

D alkaline batteries are rated for 20,000 mAh at a 20mA load. With only a 3mA load, they might be expected to last a year or longer.

In either case, a 4 cell pack would be required.
 

gary350

Well-Known Member
Those boards look interesting but I hope to scare people away so I don't have to deal with them. So far so good barking dog and motion detector lights are the best thing to have, a few LED lights might help. LED blinker PC boards with IC for sale on Ebay $2 each. I already have enough parts to build a dozer LED blinkers that will be enough for now. What I was really needing is a single LED flasher circuit that works that I can build easy and cheap with few parts. I am not sure which circuit uses the less power I hope 1 circuit will run for a month on the same AA batteries. The single blinker can probably be set to blink slower to save power.
 
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JonSea

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Most Helpful Member
The idea is the radar boards turn on an LED as people approach. They get close, they see an LED go on - they've been detected. They back off, the LED goes off. They get close again, the LED turns on again. They move to a different spot. The same or a different LED turns on - detected again. They don't know if these are connected to an alarm system, a camera or something else.

The alternative is a bunch of flashing LEDs that flash all the time. Nothing changes if they get close. Don't need a whole lot of brains to figure out nothing happens.

Less than a buck a module, plus an LED and resistor. That's pretty cheap.
 

gary350

Well-Known Member
The idea is the radar boards turn on an LED as people approach. They get close, they see an LED go on - they've been detected. They back off, the LED goes off. They get close again, the LED turns on again. They move to a different spot. The same or a different LED turns on - detected again. They don't know if these are connected to an alarm system, a camera or something else.

The alternative is a bunch of flashing LEDs that flash all the time. Nothing changes if they get close. Don't need a whole lot of brains to figure out nothing happens.

Less than a buck a module, plus an LED and resistor. That's pretty cheap.
That sounds interesting. Which end of the board is the detector? Where does LED & batteries solder on?
 

JonSea

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Most Helpful Member
I don't think those boards include the radar source. They only detect radar frequencies or leakage from a microwave.
Wrongo. They are self-contained motion detectors. As I explained, I have played with them and they will detect a person through a sheetrock wall.

There's a detailed write up here.
 

JonSea

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Most Helpful Member
That sounds interesting. Which end of the board is the detector? Where does LED & batteries solder on?
It's pretty simple - details are readily available. Engineering consulting doesn't come cheap.

Here's a picture of the board. VIN is the positive power connection. If needs to be greater than 4.5 volts. The negative side of the battery goes to GND.

The LED series resistor connects to OUT. Connect the LED between the resistor (positive end of LED) and GND. Done. The resistor should be between 110 & 220 ohms for a red LED.

Connect nothing to 3V3 or to CDS.

[There's provision for a photocell, but some discussion about whether it enables the output when it's dark or light.]

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This info is from the link in the above post. Just the pertinent info so as not to get anybody lost in the details.

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JonSea

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Most Helpful Member
Next thing you know, some one will be trying to steal WI-FI from the McDonald's down the street .
I often take my laptop to McDonald's, buy lunch and work away for a while.

What I'm amazed by is at least a couple of people I've noticed regularly come in, spread laptop and stacks of paper across a table and work for an hour or two and never buy anything to eat or drink.

The location near me isn't so busy that all the tables are in use, but still. Seems like the social contract is, that if you're going to use their space, wifi and even power, you should make some purchase there. I'm somewhat surprised that they haven't been kicked out.
 

gary350

Well-Known Member
I have 2 questions.

1. Can this photo conductive cell be used to tune off this LED flasher during the day then turn on after dark.

2. If LED is removed from a working circuit will the circuit continue to run and us up the batteries?

OK I admit we are paranoid about thieves because 2 teenage boys live 5 houses from us they have been breaking into many houses in the area for 2 years. They been to jail several times. They are out of jail again they been out 2 weeks. Every time they get out of jail it does not take long 3 or 4 weeks they are breaking into houses again. Last time the boys put 2 people in the hospital for more than a week. These boys are stupid they think if no one see them they won't get caught but they don't realize they have a history of breaking into houses, they will be the first suspects. We talked to the police for 30 minutes we were told, courier criminals usually get more aggressive they soon begin to think dead witnesses will keep them from getting caught again. Police office said, buy a gun and don't be afraid to use it these boys already have a criminal history that gives the shooter an advantage in court. I just want to scare these 2 boys away, I don't want to shoot anyone. My attorney said, If you have to shoot make sure they are dead, if they are injured they will sue you and you may be paying them a monthly check the rest of your life. WTF type legal system do we have? 5 police cars were at the boys house last night with lights flashing, today I see the 2 boys smoking cigarettes in the yard, I have no clue what was going no last night.

I ordered a bargain pack 100 PNP transistors $3 free postage from Colorado they will be here in a few days.

https://www.ebay.com/itm/3-x-Photo-Conductive-Cell-650nm-LDR-RADIAL-5mm-USA-SELLER-Free-Shipping/233103896211?hash=item3646132e93:g:bekAAOSw6BtVT9kO
 

JonSea

Well-Known Member
Most Helpful Member
I have 2 questions.

1. Can this photo conductive cell be used to tune off this LED flasher during the day then turn on after dark.

2. If LED is removed from a working circuit will the circuit continue to run and us up the batteries?
1. I ready don't spend time typing this stuff up for my health. As I stated already - I don't know anything additional:

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2. Why would you remove the LED and leave the module powered? That makes ZERO sense.
 

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