Helmet De-Construction

[Witch]

Ok everyone, before you start asking why I want to take my helmet apart, let me explain.

 

First, I want to paint it. White doesn't do it for me.

 

Second, I may need to replace the speakers.

 

Third, I'm adding a volume control, possible to each speaker seperatly. No, I don't know how yet.

 

Andso, I figured out how to get the stuff that's screwed on off. That styrofoam liner has me baffled. How is it held in there? Glue?

 

If any of ya'll can give me some insight, I'd appreciate it/

 

Later

[Gomer Pylot]

Don't take out the styrofoam. It's not necessary, and if you do, then you have destroyed the impact resistance. It will never, ever, be the same, and you may as well wear nothing, it's just weight on your head. You can do everything necessary with it in place, if you know what you're doing. But if you want to go ahead and screw it up, it's yours, so have fun.

[Gunner]

I rebuild flight helmets. You can remove the styro liner just as long as you replace it w/ a brand new one. You can find new liners online from various sources.

Replacement of speakers is easy just make sure that when you put the new ones in you have the white wires on top so if a speaker blows you can still hear out of the other... PM if you need help. I suggest oregon aero upgrades....

[Superman]

Depends on the type of headgear you have. If it has the Web headgear in it, then it is glued in. If you have a TPL liner then the styro liner is held in with Velcro, but it is still very hard to remove without damaging it. Gomer is correct in that you don’t need to remove it, but you can buy a new styro liner from flight suits.

 

 

The volume problem is probably due to the R22’s pi$$ poor intercom system.

 

 

Clark

[darwin]

Witch,

Fundamentally, do you want to be able to adjust the volume DOWN from whatever the MAX is, or is the volume still unacceptably LOW even when set at MAX?

 

If you want MORE volume than max, you will need a powered amplifier. You will be best off just buying this.

If you want LESS volume than max, you will need an attenuator. This I can describe how to build.

 

-Darwin

[Gomer Pylot]

To attenuate the volume, all you need is a potentiometer to increase the resistance. These are commonly known as volume controls, and can be put on the helmet or inline on the cable, depending on what you get. Using the volume control on the ICS box is the best way to do it, but if you have a really, really cheap one with only one volume control for two pilots, then you may need a separate one on your helmet or headset. Many headsets come with volume controls on them, but for some reason they don't put them on helmets, maybe because most helmet users fly aircraft that have real ICS systems.

[Linc]

The military SPH-4 was glued in. The SPH-5 and HGU-56/P use velcro. It required a modified cake spatula for us to take either one out. Anything else would result in significant damage to the styro liner and cause us to have to replace it.

[Witch]

Thanks guys.

 

Yes, the liner is stuck in there and I was very wary of removing it. I can still paint the helmet, no problem. I just need to keep laquer thinner out of the mix.

 

I took the speakers out and boy am I disappointed. First off, there's only a piece of foam holding the speaker in place. I guess it serves the purpose, but it seems kinda cheap. I'm going to add more acoustic foam and see if that kills the engine niose a little. If not, I just might try to install some sort of anr in it.

 

As for th evolume, the pot in my DC's is 1K Ω. Radio Shack has a 5K Ω, but I think I might do better at Norvac-I hope. The problem is that Mikes headset overpowers mine and I get blasted in the ears. I know it's because Robinson doesn't have any biasing resisters in the system. It totally sucks.

 

Thanks again.

 

Later

[Gomer Pylot]

If you really want to go all the way with the pot, try Mouser. They have everything you can think of, and more. But the RS pot will work fine, if it fits. 1k or 5k or whatever will work, the higher resistances will just attenuate the volume more, but will be the same at zero.

 

You may be able to get more foam in the domes, and it might help. Earplugs are guaranteed to help, and are cheap. The school should have them available for free.

[Witch]

You may be able to get more foam in the domes, and it might help. Earplugs are guaranteed to help, and are cheap. The school should have them available for free.

 

Thanx, I'll try that the next go-round.

 

Later

[Linc]

I took the speakers out and boy am I disappointed. First off, there's only a piece of foam holding the speaker in place. I guess it serves the purpose, but it seems kinda cheap. I'm going to add more acoustic foam and see if that kills the engine niose a little. If not, I just might try to install some sort of anr in it.

Go with the hush kit from Oregon Aero as Gunner mentioned (and I think you did, too). I know guys who swear by them, and the USAARL just did a study that demonstrates they seriously improve the noise reduction qualities of the helmet. But, stay away from the earcup replacement products. They don't provide energy attenuation in the lateral axis.

[Superman]

The problem is that Mikes headset overpowers mine and I get blasted in the ears. I know it's because Robinson doesn't have any biasing resisters in the system. It totally sucks.

 

 

Witch,

 

I’ve been thinking about this volume control idea of yours and I’m wondering if it is worth the trouble.

If you turn down your volume control on your helmet to where the intercom volume doesn’t blow your eardrums, then the comm. radio volume will be too low for you to hear. If you turn up the comm. radio volume so you can hear it, then it is going to blow Mikes eardrums. Without a real audio panel and intercom, I’m just not sure it will work…… But if you had that, I guess you wouldn’t need the volume control anyway.

 

Clark

[Witch]

Well that's the rub, isn't it? I mean on one hand you're lowering the volume to a comfortable level, but because the Robbie has no bias resistors, you can't hear anything. It's a pain. One thing though, Mike was saying to me that with all the radios going and the ICS in the Crane, he's wanting to put a pot on each speaker on his helmet. Great idea, but I'm not sure that one pot would interfere with the other. He'll talk with his avionics guy to work that one out.

 

My DC's can handle the volume fine though. I'm wondering if I ought to get a cheap set of DC's off Ebay and do a Frankenstein on the both of them. Egor!

 

In the meantime, I'll add foam and stuff and get it painted.

 

Later