Radio based hit detector

[Bruce3]

A while back I was have trouble confirming hits on steel at long distances. I looked at getting a Magnetospeed T1000 hit indicator but didn't want to spend the money. I looked at making one myself. In typical fashion I spent even more money on designing my own hit indicator. The unit plugs into a walkie talkie or Ham radio and the sensor, on a 10ft wire, attaches to the steel target. When the sensor detects an impact, the word "HIT" is transmitted over the radio. Below is a demo and the unit in action,

 

[entropy]

Does it add three dots at the beginning when you miss?

 

[ExtremeSquared]

Any thoughts on shielding the antenna from impact?
I imagine you could turn hardened chain into a radiating 2m element if it is mounted appropriately. Then mount the whole setup behind the steel.

 

[Doug444]

Yeah, my same question - protection from misses. I know, the odds are astronomical, but with my luck, half-way through the first string bullet spatter or an errant round will damage something way out yonder.

ETA - I've RSO'd a few long range matches and sometimes it's downright challenging to verify hits.

 

[Bruce3]

In terms of shielding the device from impact, you could place it behind a barricade, because it doesn't rely on line of sight. The unit uses a 10ft wire to put distance between the target and the main device. This wire can be lengthened to reduce the chance of catching a stray round.

 

[Heir Kommt Die Sonne]

Any of you played Pole Position to the Atari? Like from the 80s. Dont know if the Atari version or the Arcade but theres a version of the game that has a heavily digitalized voice that says "prepare for standby"
If I use this hit spotter device thats the kind of vocal font I want on the radio saying HIT

EDIT: I actually like that setup. I dig it. I'd probably want it even if I don't have issues seeing an impact. Might try this myself.

 

[Bruce3]

Any of you played Pole Position to the Atari? Like from the 80s. Dont know if the Atari version or the Arcade but theres a version of the game that has a heavily digitalized voice that says "prepare for standby"
If I use this hit spotter device thats the kind of vocal font I want on the radio saying HIT

EDIT: I actually like that setup. I dig it. I'd probably want it even if I don't have issues seeing an impact. Might try this myself.

I think it would also be useful if other people are shooting steel too and you want to discern your hit from others.

 

[ExtremeSquared]

Have you dabbled in OpenCV at all? It is surprisingly simple to implement complex image processing on a Raspberry-PI-like board. Next step is a camera-based hit detector that sends back hit coordinates in x,y mrad offsets using morse. I bet you could get either paper or painted steel hit detection running in under 200 lines.

 

[Bruce3]

Have you dabbled in OpenCV at all? It is surprisingly simple to implement complex image processing on a Raspberry-PI-like board. Next step is a camera-based hit detector that sends back hit coordinates in x,y mrad offsets using morse. I bet you could get either paper or painted steel hit detection running in under 200 lines.

Very interesting. May have to take a look into that!

 

[jmorris]

I have used automotive alarm shock sensors and LED brake lights before.

Even triggered other stuff with the same sensors.

https://www.youtube.com/shorts/vp04FpsUl6w



This style works without any electronic gadgets. When the steel is hit, it rocks back and you see the rear red part, you can’t see when it’s blocked by the black part at rest.



These are still my favorite way to shoot steel.

 

[Bruce3]

I have used automotive alarm shock sensors and LED brake lights before.

Even triggered other stuff with the same sensors.

https://www.youtube.com/shorts/vp04FpsUl6w



This style works without any electronic gadgets. When the steel is hit, it rocks back and you see the rear red part, you can’t see when it’s blocked by the black part at rest.

View attachment 1136452

These are still my favorite way to shoot steel.

Wow that's some pretty ingenious targets. Nice work!

 

[jmorris]

Thanks, I ordered one of these back in November, supposed to get it this month, doesn’t look like that’s going to happen though.

https://autotrickler.com/pages/shotmarker

A watched clock stands still…

 

[jmorris]

Any thoughts on shielding the antenna from impact?
I imagine you could turn hardened chain into a radiating 2m element if it is mounted appropriately. Then mount the whole setup behind the steel.

We use conduit (EMT) attached to the frame that holds the steel so the sensor and light are off to the side and slightly ahead of the steel plate, the vibration travels through the tubing.

 

[herrwalther]

Should program it to say "Way off" when you miss.

I think the Army was experimenting with something like this by the time I was getting out. Sensors were being used to count hits at rifle qualification. Namely because some of those green dummy targets are so old with so many rounds through them you could throw a softball through them and hits weren't getting recorded by the pressure sensors. The audio sensors either picked up the proximity of the round or something. I registered some "hits" by shooting the berm in front of the target on some targets that had larger than normal holes.

 

[Jim Watson]

Should program it to say "Way off" when you miss.

Which is why I'd rather have a paper target and a camera.

 

[230RN]

Does it add three dots at the beginning when you miss?

Coffee splurter. Had to wait for it to dry before posting this.

Reminds me at the time I took my code test (mid 1970s) , one of the character groups (I was warned by my Elmer) would be E, I, S, H, and 5.

(dit, didit, dididit, didididit, dididididit.)

Turned out instead of random 5 character groups, by that time they had changed to a "realistic" QSO in code. Questions were, like, "What kind of antenna was the sender using?" and day-to-day things from the QSO.

(QSO = conversation (by code or voice) between two hams on the radio. See "Q-Codes.)

Punch line for entropy's joke? Three dots = "S, added to the "HIT" in code.

Beats spelling out "Maggie's Drawers" in code.

73

 

[Reloadron]

Nice thing about shooting a target, any target, is line of sight. You aren't trying to transmit a hit around corners or through walls. Yes, got my first ticket in '63 when I was 13. Over the years with job, travel, kids my Ham Radio days were set aside. Been thinking about getting back into it. Retired now at 73 and the kids have homes and kids of their own and while I have the indoor range my outdoor range is a frozen tundra. Plenty of time to reload and look for a QSO.

'73s
Ron

 

[230RN]

^ Code is no longer required by international agreement.

With the mods' permission since pure ham stuff is off topic:

I shot a CQ into the air,
It fell to earth, I knew not where;
For, so swiftly it flew, the sight
Could not follow it in its flight.

Especially since it bounced around a couple of times between the ionosphere and the planet.

With apologies to Longfellow.

And to the mods.

Back on topic, please.

DE Terry

REF:
https://en.wikipedia.org/wiki/CQ_(call)