The PVS-31s are the ultimate in binocular night vision goggles. They are made by L3 Technologies and the price tag is not for the faint of heart. Just ask fellow writer Richard L. he has a set. PVS-31 cost around $10k. Well in the world of night vision users, specifically airsoft night vision users there have been some really clever individuals using a dummy set of night vision and converting them into functional dummy PVS-31. Typical binocular night vision like ANVIS6/9, Sentinels, and RNVGs are not articulated. The PVS-15 is but has a limited range for the monocular pods. The DTNVG and PVS-31 have a full range of motion and the monocular pods have magnetic switches that shut power to the tubes when they are folded open or the unit is folded up against the helmet. With the dummy PVS-31 as a starting point, you have the articulation due to the bridge design.
Jeffrey Melochick PVS-5/31
This recent trend in modified functional dummy PVS-31 was spearheaded by Jeffrey Melochick. He started off by 3D printing adapters to mount PVS-5 monoculars to the dummy PVS-31.
What are these dummy PVS-31? They are made by a Chinese company called FMA.
They are nothing special. Just a replica toy housing with some green LEDs inside. However, the PVS-31 design lends itself to be easily modified for use with real night vision.
The monocular housing is bolted to the articulating arm using 4 small screws. If you can bolt on a self-contained unit and route power to the monocular then you can have working night vision.
This is why Melochick used PVS-5 monocular housings. While the PVS-5 is a fixed goggle design, the eyepiece, image intensifier tube and objective lens are all self-contained in a small monocular housing.
Night Eye Binoculars posted a modified pair of PVS-5 monocular housings into a slimmer binocular setup.
Here are some more of Melochick’s modified functional dummy PVS-31s.
As the saying goes, “there is more than one way to skin a cat”. There are other ways to make functional dummy PVS-31 and that is with the use of ANVIS monocular housings. Why can’t you just put an image intensifier tube into the dummy PVS-31? Well, it won’t fit and you need to figure out how to put optics on the monocular housings. The PVS-5 is great but you are limited to MX-9916 image intensifier tubes and they are not really made anymore and no current night vision device uses those. Most night vision uses MX-11769 or MX-10160 tubes. 11769 have pigtails for manual gain control like in a PVS-14. But most binocular night vision does not have manual gain so a 10160 tube is your best bet. The tricky part is getting power to the tube and having optics both front and rear to actually see and use night vision. Well the ANVIS monocular housing solves this problem. With the tube installed and the right optics, you have a self-contained night vision device. And all you need now is 3V to power the tube.
So some people, Melochick included, have made 3D printed adapters to mount the ANVIS monocular to the dummy PVS-31 bridge.
Convert Your Binos To PVS-31
Francisco Garcia modified a set of ATN binocular night vision goggles and mounted them to the dummy PVS-31 bridge.
Looking at the ATN binoculars above, they do not have interpupillary adjustment. You cannot adjust the two monoculars to match the space between your pupils. Also, the monoculars appear to be bolted to the bridge. So Francisco cut an aluminum plate to bridge the gap between the PVS-31 bridge arms and the wider footprint of the ATN monoculars.
Francisco wired it up with a switch and remote pigtail to run a remote battery pack or a CR123 stored inside the housing.
A recent development is shrouded in vague Instagram posts. Apparently, there is something called a BNVD-1431. These seem to be based loosely on the L3 1531s.
One of the downsides to the PVS-31 is the fact that they do not have a rear diopter. That is partially why they are so lightweight. You only have front objective focus. You cannot adjust the rear eyepieces for your eyes. However, 1531s have rear eyepieces like a PVS-14. Which is the benefit to these new BNVD-1431 coming out of China.
Not much is known about the BNVD-1431 and not a lot of good content other than still photos and this one brief video.
If the BNVD-1431 are legitimate night vision housings then this could be a new competitor for affordable night vision. Most night vision bino housings are $1200+. The DTNVG out of Luxembourg is $2,800 and that is without the optics or tubes but they do articulate and are very robust. Hopefully, more people get their hands on these BNVD-1431 and produce some reviews or content with them so we know if they are worth getting or not. Otherwise, you can try your hand at building your own modified functional PVS-31.
The FMA dummy PVS-31 is around $50. Printing an adapter to mount ANVIS or PVS-5 housings will probably set you back $50-$80 depending on who you have design and print them. I believe Melochick was offering his adapter for $80. Then you need the monocular housings, optics and most importantly the image intensifier tubes. But you could easily have a functioning housing for well under $1,000. Then just add the tubes.
Source: The Firearm Blog