Poor-Man's Target Camera

[pettypace]

I've been trying to get back into 200 yard off-hand rifle shooting after a 20 year layoff. Sadly, during those 20 years, my rifles seem to have lost much of their old accuracy, my shooting jacket seems to have shrunk a couple sizes, and my old B&L spotting scope can no longer resolve .30 caliber holes, let alone .22's.

There may be no hope for the rifles and the shooting jacket, but I'm working to replace the B&L scope with more modern technology based on this little camera:



These things cost less than $10 from Amazon and once you figure out how to get some (free) code onto them, they will turn themselves into a web server and send reasonably high resolution pictures to your smart phone over a wifi connection.

Of course, it's not quite that simple. The camera's wifi antenna is etched into the printed circuit board behind the "ESP-32 CAM" lettering. The antenna is tiny and doesn't provide nearly enough "gain" to transmit a usable signal from the 200 yard butts back to the firing line. But those old stories about hackers using antennas made from Pringles cans to break into unsecured wifi networks are not just urban myths. A Pringles can might work. But in keeping with the "Poor Man's" theme, an old Foster's can is better. Here's my prototype "cantenna" which can do 200 yards but probably strains FCC regulations.



Finally, here's a screenshot from my phone at the firing line showing a few .22 caliber holes in a target at the 200 yard butts. The actual image from the camera shows the entire target but was zoomed in on the phone's screen to give maximum magnification.

[deces]

That is a pretty neat set up you made there.

[hporter]

Great idea.

What are you using to power the camera at the target? I use a Mac too, how do you program the card? I looked it up on Amazon this morning and saw a model that comes with a high gain external camera for $11. Might be fun to try!

[uscra112]

For the non tech savvy, search "baby monitor" on Amazon. I have a steerable one mounted at the front door, and one watching the animal-feeding station to monitor for raccoons and opossums. I'd buy a third one for a range camera.

The cameras need 110vac, but any 12vdc battery and a $15 inverter solves that problem. Other than that, they're plug-and-play for as little as $50.

Receivers are rechargeable battery powered.

[MrWolf]

That is pretty neat. I have issues at times with a cheap security camera i have in our chicken coop which is only about 25-30 yards from the router and will still give me issues at times. Always impressed with the ingenuity from you folks.
Ron

[Shawlerbrook]

Wow, we have McGyver on the site .

[popper]

So the software makes a hot spot for wifi ? Yup, called cowboy antenna for Dallas fans. If you bypass the rectifier, run them from DC.

[pettypace]

Great idea.

What are you using to power the camera at the target? I use a Mac too, how do you program the card? I looked it up on Amazon this morning and saw a model that comes with a high gain external camera for $11. Might be fun to try!

1) Save yourself some headaches and get a camera module that piggy-backs with a plug in board with a micro USB connector. The Amazon ad will say something like "ESP32-CAM-MB" (the "MB" somehow signifying the USB connector). Technically, you don't need the USB. But that's the easiest way to connect the camera to your computer to upload software and to a 5 volt USB "power bank" to power the camera at the range.

2) The biggest challenge will be getting software uploaded to the camera for the first time. There are several finicky little details that have to be just right for the upload to work.

3) The most common way to get software onto the camera is through the "Arduino IDE." There are versions of the Arduino IDE for Macs, Windows, and Linux. Just Google "installing Arduino ide" and follow the steps.

4) Once the Arduino IDE is installed on your computer, it needs to be up-graded for the ESP32 board. There are plenty of youtube videos with titles like "getting started with ESP32 and arduino" that will try to guide you through the process. I found many went too fast through computer screens of text too small to read and with accents too foreign to decipher.

One notable exception is a guy I think of as the Mr. Rogers of electronics videos. He goes so slow it will put you to sleep. But if you can stay awake for three minutes of this video (from about 9:20 to 12:35) you should be able to get the Arduino IDE ready for the ESP32.

Note that at the very end of those three minutes (at about 12:30), Mr. Rogers leaves you scrolling through a list of ESP32 "boards" for one that matches your camera board. What you need is something called "AI Thinker" about a mile down near the bottom of that list of boards. Sooner or later you're gonna need to find that board and select it for any program to work as intended on your camera.

5) Some thoughts about antennas: The camera modules all come with a little plug on the circuit board to attach an external antenna. But the wifi radio is wired to the internal antenna on the printed circuit board -- not to the external antenna plug. In order to switch from the internal PCB antenna to the external antenna plug, you need to de-solder a tiny "zero ohm resistor" from its present position and re-solder it into a new position a tiny distance away. Tricky business at best. A ruined camera module at worst.

A much better solution is to buy a second ESP32 module -- a non-camera version -- that comes with no printed circuit antenna and already has the external antenna plug properly wired into the circuit. This second ESP32 can sit down range (but out of the line of fire) and serve as a wifi link between your cell phone and the camera. If you then wanted to set up targets at, say, 50, 100, and 200 yards, you could have a stand-alone camera at each target with the non-camera ESP32 serving a web page to your cell phone that allows you to easily switch among the three cameras at three different ranges.

Another scenario is that you have a couple compadres shooting with you. You could have three different cameras looking at three different targets at, say, 200 yards. Then, back at the firing line, each shooter could look at his own target on his own cell phone.

[15meter]

Guess I need to recruit the electrical engineer nephew and put him to work.

But I need 300 yard range, I can still resolve .20 holes @ 200 yards(on most days), 300 the mirage comes in to play big time.

[pettypace]

Guess I need to recruit the electrical engineer nephew and put him to work.

But I need 300 yard range, I can still resolve .20 holes @ 200 yards(on most days), 300 the mirage comes in to play big time.

300 yards shouldn't be that hard. Here's a screenshot of a wifi scan from the firing line with the camera cantenna at the 200 yard butts.



The dBm units used for signal strength seem weird at first. But the rule of thumb is that doubling the distance will lower the signal strength by about 6 dBm. In other words, the -74 dBm signal from the camera cantenna at 200 yards should be something like -80 dBm at 400 yards -- weak, but possibly usable.

But that's just with a directional antenna on one end. You can easily have a cantenna on both ends which I suspect would give you 1000 yards with clear line of sight. Just just keep in mind that FCC regulations apply even to old Forster's beer cans.

[wesson357]

Your antenna is for receiving at the shooter end or at the target to transmit the signal better?

[pettypace]

Your antenna is for receiving at the shooter end or at the target to transmit the signal better?

I've tried a single cantenna at the target -- either directly on the camera module or on a separate ESP32 access point to which the camera connects. I've also tried a cantenna on both ends. Never tried a single cantenna at the firing line.

[15meter]

Just just keep in mind that FCC regulations apply even to old Forster's beer cans.

But I shoot at a club in Maybee, if they can't come up with a real name, I doubt that the FCC can find us. 50% of the time the cell phone service is non-existent.

[popper]

I suppose one could also get motion sensing SW for it. Interesting security cam without cell costs.
Edit: Code for motion sensing with separate PIR - IR motion sensor.
https://github.com/curiouselectric/L...ster/README.md

[uscra112]

"Cantennas" have got to be extremely directional. How the signal would be detected outside the beam(s) seems a non-issue.

[jmorris]

I have used broken drones for the same purpose.

Once some kid has destroyed their ability to fly, often the camera and TX are still fine. Just set it on the ground I from of your target stand.

[uscra112]

VERY good! Range won't be an issue with one of those, and they are by default battery powered.

[45workhorse]

I wish you all would speak English.
How do you get the picture to transmit down the string between the two soup cans?

[uscra112]

Now I'm dreaming of how to have a drone transport targets out and back. Would be a great boon for me since with my handicaps I can't walk more than 50 feet or so, and even that costs me.

[725]

I'm with you 45workhorse. Technology makes my head hurt.