ROSW

If you do look at Lee, skip the single stage and check out the classic turret.

I'm an embedded developer (hw & sw) by trade but a real novice when it comes to Android development. If you are still interested, please send a PM and let me know what you have in mind.

Here's the PCB.

Here are the pictures. Attached to ProChrono By itself with Velcro for mounting. Two AA batteries for power. Powers ON when ProChrono is turned ON. No switch required.

Oops. Been offline for a while. Will try to get pictures posted soon.

Sorry about not following up. Lots of excuses; didn't see much interest on the forum; day job; lazy. I built up a couple of the boards when they came in and everything worked as expected. The unit plugs into the PC and is in a small plastic case that velcros to its bottom. It uses 2 AA cells and there is no power switch; turning ON the PC turns it ON; turning OFF the PC turns it OFF. I have considered creating an enhanced version of the code which has a display window that mimics the PC display. So far that is on hold. If there is interest I'll try to post some pictures of the hardware.

I recently bundled up my new Pro Chrono Digital and a laptop with the program on it and took it to the range for the first time. The Pro Chron worked great but the laptop program was a disaster. I could see the Pro Chron display fine but the laptop was unusable in the bright sunlight. Being a embedded developer I decided to design a commercially viable solution using my Android phone (or tablet) and a Bluetooth module to communicate with the Pro Chrono. I've looked at the other postings to this forum and enhanced them where possible. 1) FCC certified Bluetooth module 2) no switch - automatically turns on/off with the Pro Chrono 3) uses 2 low cost alkaline AA batteries for about double the run time of a 9v battery 4) 'velcros' to the bottom of the Pro Chrono. 5) Professional PCB. The Pro Chron display is quite visible and adding a numeric display to the app would make the buttons much more difficult to use, especially in sunlight. Therefore the Android app is VERY simple - 6 BIG, BRIGHT buttons. Today I called Competition Electronics to see if they would be interested in the design. They politely informed me they had a design in the works, so no. So here I am. I have parts for about five gen 2 boards coming in later this week and the Android app has been working on my gen 1 board for some time. Being a pre-production small run, the cost is high - a bit over $50 per board (no profit). I expect in moderate production the cost (not price) could get down to the $20 range. The Android app is not on the PlayStore and is not protected (at least at this time). So my question is - is there any interest? and if so, where and for what? -ROSW PS Will post photos of the gen 2 module when I get one built up. PPS Sorry, there is no iPhone app. Apple in all there wisdom and to protect the user experience, requires an authorization chip for Bluetooth modules to connect. And once you get authorized to buy the chip from them, you must build the device it uses in an Apple approved facility. I have ideas on how to get a solution using an iPhone, but that will need to wait, at least for a while

Thanks. Much appreciated.

Other than the bullet being detected by both the front and back sensors, the next most important thing to accurate readings is to have the bullet go directly through the two sensors (the shortest distance). Any angle will increase the distance the bullet must travel which in turn decrease the reported velocity.

I've been shooting rifles since back in the '50s. Started with a 30-06 my father built back then and am still taking it to the range these days. Introduced each of my sons to shooting as they got big enough. About a year ago my son brought along a couple of pistols on a trip to the range and offered to let me shoot them. I've been hooked ever since. Purchased my first hand gun soon afterwards followed by ... and ... and ...(you get the idea). I found this forum last week while doing a web search for the serial protocol info for the ProChrono. I WAS planning on designing and building a Bluetooth interface for it but I soon realized all the work has already been done. However because my day job is designing and building battery powered, radio linked commercial gadgets, I hope to be able to contribute to all the effort that has already been done. I must admit though, there is not much work remaining.

You are welcome. Didn't think of it at the time but Jameco is another source that may carry then at a reasonable price.

Give DigiKey a try. Prices are about the same as Mouser but you can ship USPS for less if the weight is low enough.