I'm using my TNVC, PVS-14 in a Night Cap, attached via the plastic J-arm that came with my kit. It's attached via a Wilcox shroud and L4, G11 mount.

Recently, whenever I turn my head to look straight up at the sky, to look at the stars, it shuts off. This happens without the unit being tilted up in the mount. If I do it slowly, it does not happen. But if I move my head fast, to look straight up, it shuts off.

I cannot get it to do this with the unit removed from the mount.

Can anyone give me advice? Is something lose or is this some "tactical feature" that I'm just discovering?

Yes, I am prepared to be identified as a stupid newb.

You're falling victim to the auto-shutoff "feature" of the PVS-14, which automatically turns the unit off when it it is flipped, even without the power switch being cycled.  

This is accomplished through a highly unreliable combination of magnetic, gravitational, and electronic sorcery, and often causes confusion and irritation with new users in a variety of situations.  

Luckily, there are a number of ways to "defeat" this "feature," but by far the easiest is to simply cut small squares of electrical tape, and to put them over the two contacts on either side of the threaded hole for the J-Arm before installing it.

This does, of course, require you to remember to switch off your PVS-14 before flipping it up, lest you have a green glowing beacon floating over top of your head, but this should be SOP anyways because of the aforementioned unreliability of the auto-shutoff feature--invariably, it will always shut-off when you don't want it to, and won't shut-off when you do.  

~Augee

^^^What he said.

+1 for all of this but I would like to add:

I just disassemble the J-Arm and gut the "feature" altogether. While I'm in there I chamfer all of the nesting holes for the position locking nubs so the adjustment you choose to fit you locks more permanently and stable once it is adjusted for you. If your J-Arm has the newer rectangular teeth then this does not apply to you.

OK. I'll play around with it. I had heard (read) that the J-arm has an auto shut off feature when it is flipped up. But I am NOT flipping up the unit. I'm simply looking up at the sky with the scope still over my left eye. More interesting is that it does not do this all the time.

Anyway, as long as nothing is wrong with my 14, I can live with the irritating engineer designed because-I-know-what-you-will-need-better-than-you feature...

Thanks for the advice.

Momentum. Note you said going slowly doesn't do it. Doesn't take much for the inertia to initiate it shutting off. 


Super fun when you're driving. 

The auto-shutoff feature is totally unpredictable.

It isn't that someone thinks that they know better than you do. This was designed poorly and malfunctions erratically. If it worked properly then it would be a neat feature. As it stands, I would defeat it. It's a pain to deal with. All you need is the main switch.

I took someone out on hike a couple of weeks ago and his PVS-7B was doing the same thing. I didn't have any issues because my J-Arm is gutted.

Due to the evolutionary traits that I see in night vision gear, I am led to believe that there has been an insufficient amount of input from dynamic field users and an excess of input from sedate labcoat wearers.

The ergonomics and ruggedness that should be easy to achieve are slow to materialize compared to the advances in technology.