What do you do when you can’t find a max tracer unit for your hop?

[simonh]

Well you make your own!

View attachment 129492View attachment 129493View attachment 129494View attachment 129495

 

[Rogerborg]

Oh, nice one. I've tracered up a couple of peasant hop units, but just with LEDs inset into them and a single resistor inline in the wiring, nothing that fancy.  Is that 2 LEDs per side?

 

[simonh]

2 leds per side, one set of UV one set of blue (UV light up red tracers better) two would probably have been fine but why take chances

I think I could do a neater job for the next one

 

[Sewdhull]

That's cool. What's the forward V on the LEDs, do you need resistors at all? 

 

[simonh]

I can’t recall offhand but I did the calcs and the resistors are needed, I tried a few variations and blew lots of leds in the testing

 

[Sewdhull]

ok, the UV leds i was looking at were I think, 3.5 fV so 4 of those, even 3 would be under or around battery voltage in series. Looks like yours are parallel tho so you'd need the current limiters.

LED drivers are cheap, so that's another possibility.

 

[simonh]

3.2-3.8 fv - I am running them off a 9v battery, the resistors are really small IIRC, I bought them off bright components for pennies really and yes running parallel. One 9v lasts around 6 hours or so. 

 

[simonh]

V1 was a failure, far too bulky.

v2 is better.View attachment 129694View attachment 129695View attachment 129696

 

[Pseudotectonic]

do these light up BBs better than tracer units? since this is a constant light

 

[simonh]

I’ve not yet tested this with bbs yet, my son has run a mad bull tracer hop for years and I never noticed the bbs out of that being any brighter than ones through my flash unit tracer.

this one is a lot brighter than the mad bull unit though so I guess we will see.

we can’t fit a tracer unit on this gun as it has an integrated silencer so one can’t be fitted.

 

[Sewdhull]

A slight aside, the Perun hybrid mosfet has power out put for such things as magazines and tracers.

Also I'd be tempted to connect the LEDs in series or parallel/series ( since you have 4 leds), you'd only need one resistor for limiting if any.

A project I'm interested in myself.

I notice that my UV torch makes for less bright tracers compared to pretty much all my white torches. Did you test the LEDs shining on a bb to gauge the effectiveness of the white or UV leds?

Sorry for all the input.

 

[Pseudotectonic]

Very tempted to do this, what wavelengths of an LED do I need for green and/or red tracer BBs?

My googlefu says I might need around 470 nm (a blue light) for charging red tracers assuming they are calcium sulfide based... but I am really not sure

Anyone know the correct numbers / absorption and emission spectra? And for green ones? In the UV range?

 

[Sewdhull]

365nm emitters are cheap and as UV as you need. White LEDs will do the same thing, which ironically are UV LEDs with a phosphor coating. Shine a torch on the bbs and you will see a wide range of light wavelengths will activate the phosphors. It will depend on what phosphor is used.

I do not think it matters about the tracer colour. Red is not as bright to our eyes as green at the same energy and phosphors favour the green...

 

[simonh]

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All back together, not running any resistors for the moment, I can always add some in if it proves unreliable.

i know blue leds light up green BBs well, the UV ones are for red tracers, we generally run a mix of both just because… 

I have some white leds as well but the blue/UV mix just looks a bit cooler in the side of the gun.

The gun this is in is HPA so no mosfet required.

i do like to run a separate battery feed for the built in tracer mostly just because that is how we’ve always done it and you can choose to run the tracer or not.

 

[simonh]

IMG_2643.mov

 





3A00C86E-54D1-4EA1-AA40-D607AA058CB2.mov

 

 

[AttackBunny]

This is awesome, fair play for having a hand steady enough to solder something so small ? 

is it just a case of battery input - resistors - LED  or more then that? 
thanks! 

 

[simonh]

there are online calculators that you put in the LED voltage, no of LEDs circuit type and battery supply and it will tell you what resistors you need.

I can assure you many many LEDs were destroyed in this process as I practiced!

 

[simonh]

It’s been out for its first game day today at Gaol, and while most of the gameplay ended up being outdoors, this did work brilliantly for the indoor sections.