Let's talk IR emitters

[SoCalBobS]

I have a few questions or items to discuss about our upgraded IR emitters.

Stock Heng Long emitters are usually behind a 2 or 3 mm aperture, usually set back only 2 mm or so. Why do we set ours back ~ 9 mm? Is it because we often place them in the barrel, which has a 6mm bore? What are we trying to avoid, a wide spread hit capability? If this were the case, would placing them in the original spot behind the original smaller opening achieve the same result? When we do install them in our barrels, should we also include a smaller than 6mm diameter sleeve? Does narrowing the diameter give a stronger beam as well as a narrower one? I've heard that the newer Heng Long IR bulbs have a respectable range. Has anyone compared them side to side in the daylight?

Just thought I'd wake everyone up a bit...

[tank_me]

The Tamiya tanks come with the barrel clamp IR emitter and if I remember correctly the LED is set back about 9mm from the end. I'd have to dig my KV-2 one out to verify that. That was the original standard they were trying to standardize on. The HL tanks weren't really even a consideration in the process. The point of having it set back is to narrow the beam so you can't "shotgun" a bunch of tanks at once or tanks really close to the emitter that are not intended targets. Now that there are so many different tanks with different mounting points, the 9mm set back just got applied to all tanks by the clubs running the battles...Tamiya or other.

I know other folks can weigh in on the emitter characteristics as they have done testing on the various LEDs available.

Derek

[Rubicon99]

I have a few questions or items to discuss about our upgraded IR emitters.

Stock Heng Long emitters are usually behind a 2 or 3 mm aperture, usually set back only 2 mm or so. Why do we set ours back ~ 9 mm? Is it because we often place them in the barrel, which has a 6mm bore? What are we trying to avoid, a wide spread hit capability? If this were the case, would placing them in the original spot behind the original smaller opening achieve the same result? When we do install them in our barrels, should we also include a smaller than 6mm diameter sleeve? Does narrowing the diameter give a stronger beam as well as a narrower one? I've heard that the newer Heng Long IR bulbs have a respectable range. Has anyone compared them side to side in the daylight?

Just thought I'd wake everyone up a bit...

Bob the HL emitter opens are much smaller then the Tamiya opening or barrel placement opens. The smaller opening has a similar effect on the beam as would a 9mm set back. The issue with the smaller emitter opening comes when the use of an HP bulb is added. These tend to have enough energy that the smaller opening and 2-3mm HL set back becomes insufficient and the tank starts "shot gunning" the field with a spread that exceeds a 45 degree arc.

The newer HL emitters are actually pretty decent. I would place them somewhere between the stock Tamiya and HP bulb in performance. They have a good range when new (at least 150ft against a Tamiya IR receiver and about 120ft against a LegoDEI), but the range does fall off rather quickly as they age or if they are used in bright sunlight. By comparison the HP bulbs have about a 30ft greater range under similar conditions again both types of IR receivers and have roughly four times the usable life.

I typically run my factory HL emitters without a 9mm set back IF they are left in the stock location or until they are replaced with HP bulbs. At which point I add the greater set back.

Really the only drawbacks to a HL bulb is they do tend to loose performance (range) rather quickly and they are not always placed in the best position for IR battling.

[DavidN]

On some of my tank destroyers, I put smaller tubes at the front of the main tubes to ensure my comrades don't accidentally get shot by me.

And on some of my tanks, I had my emitters 20mm back inside the barrel and they are still good.

[oldwolf]

I have been experimenting with this as well. At present I mount my ir bulb in a 6mm diameter brass tube, which serves as a holder for smaller steel tubes. I found that a 20mm long, steel tube with 4mm id and 1mm wall, inside surface painted flat black, works ok at the longest indoor range I can set up in my house: approximately 50 ft. Indoor testing is never perfect since a lot of flat, smooth surfaces can reflect the ir and cause collateral hits. Subsequently I have slipped 2mm id with 1mm wall tube into the 4mm id one, also extending overall length to about 25mm from tip of ir bulb. This latter is giving me about the narrowness of the firing cone that I am looking for. Outdoor testing is waiting for melting of the snow cover with the coming spring. My two acres of mostly woods will only give a maximum open straight line of fire of about 120 feet. Much better than my inside distance though.
Basically, since I know of no one else nearby who is into the hobby, I want to make accurate shooting a challenge. My only “opponents” being the LegoDEI anti tank mines, set up on end to act as rpg or missle launchers.

Getting a reasonably narrow, but detectable at long range, cone of fire is a challenge.

[RichJohnson]

You need to get some local friends involved. Have a bbq, during some beer, battle some tanks on your property, they might like it and get their own.

I test my tanks quite a bit when I have to make my own IR mounts. The IDF m50 Marksman proved very challenging. I have found that the Hgh power (Heat rounds) as we call the the IR led here, tends to shoot right through plastic and hit tanks right next to you. It seems to be able to go through at least one layer of styrene. Urethane is denser and seems to shield it adequately so far. I too try to use a brass tube where possible. The optimum seems to be a 9 mm set back in a 5mm tube.
always remember to test backfire. IR does come out of the rear of the bulbs and if you mount it exposed it will hit tanks behind you.

[oldwolf]

I secure the led in its brass tube with a good size glob of blu-tac. I am pretty sure it is opaque to ir and at the same time lets me pull the led out fairly easily if it fails.

It would be nice to experiment with neutral density filters made for ir but they are expensive and dont look easy to cut and fit to something. Regular neutral density filters for photography are transparent to ir, as far as I know. If cheap, easily cut neutral density filters for ir could be found it would be a simple matter to simulate different armor thicknesses for the front, sides and rear of a tank.

[BcuriousR]

FRAG uses a restrictor. The tube is 3/4"-1" long. The hole in the end is drilled with a #52 bit.

[oldwolf]

Interesting, FRAG is very close to aperture and bulb set back that I am experimenting with. Maybe I am not as far off track as I thought I might be.

[oldwolf]

This is how I have the ir emitter mounted on my centurions. 2 mm id for the opening.

[DavidN]

How about the latest HL IR receivers on their tanks, are they any good? Or do we still need to replace them with LegoDEI? Thank you!

[RichJohnson]

We know the HL small black mushroom with the dome on top really does not work well by any means.
if Hl has a new Ir receiver we have not seen it yet. So stick with the Lego DEI as they work very well.

[Rubicon99]

How about the latest HL IR receivers on their tanks, are they any good? Or do we still need to replace them with LegoDEI? Thank you!

Still JUNK in any environment other then indoor use.

Although I have 3D printed some new "easy attachment" sun shades that do improve the outdoor usefulness. I was going to bring these to the next LA battle for the new players that have not updated yet or those that it is their first battle.

[DavidN]

Still JUNK in any environment other then indoor use.

Although I have 3D printed some new "easy attachment" sun shades that do improve the outdoor usefulness. I was going to bring these to the next LA battle for the new players that have not updated yet or those that it is their first battle.

Thank you! That's good info to know. Please persuade Mike to change the receiver on his M41. He kept saying that his receiver worked. I had to shoot him 2-3 times to register 1 hit, lol.

[Rubicon99]

Thank you! That's good info to know. Please persuade Mike to change the receiver on his M41. He kept saying that his receiver worked. I had to shoot him 2-3 times to register 1 hit, lol.

LOL!!!!! You are not wrong his tank is next to impossible to hit with that stock HL receiver. Sure it works 🥴🥴 he is not wrong, but you have to be within five feet and shoot it 2,3,4,5 times. He knows better then this, he has been at it a long time. I think as a group we need to bring it up at the next LA battle. Maybe if we all together ask him he will spend the $35 and join the LegoDEI club.

The sun shade I have made for the stock HL receivers are really intended for the very new or first time player. Not for someone with Mikes experience.

[RichJohnson]

I’ve mentioned it to him several times.

[cmdrcody]

Who has the LegoDEI for sale other than Etsy?

[RichJohnson]

DAK RC. But his may only be Clark versions. I don’t know if he has the HL type receivers.

[DavidN]

I think we just need to ask him to bring his tank out in the open with a one-on-one test. Then we can to prove that his tank needs to be upgraded.

[SoCalBobS]

Who has the LegoDEI for sale other than Etsy?

The only other company I know of offering a comparable product is DGS Military in Canada:

https://dgsselkirk.wixsite.com/dgsmilitaryhobby/henglong-ir-upgrade-kit

It's HL compatible, so presumably with Lego also. It's $50 including shipping but comes with an emitter mount too.

(Screenshot)


However LegoDEI is a member of our tanking community and has always been trustworthy.