I just started actively using an ITT Night Quest NQ PVS14 that I have. Comparing that with several quys that have newly purchased PVS14's, I debating if I should upgrade this unit.

Looking at the paperwork & warranty papers, I purchased this new in 2004 but at a significant discount as it has a somewhat big black right at the zone 2/zone 3 area. Serial # is RS 114XX. It's just recently developed a tiny but annoying bright spot or emission point literally right in the center.

Any ideas as to what tube was used in this? Would it have been comparable to Omni V or VI specs? I don't have a tube data sheet, it never came with one.

I'm not unhappy with the unit but I'm wondering if it would be worthwhile to upgrade this with a new tube and single battery compartment? If I upgrade, should I go to the latest & newest tube? Are there tubes available that, although not the latest, have enough of a cost savings but enough improvement to justify the upgrade? I really don't mind tubes with blemishes either, as long as they aren't in zone 1. Who would offer these tubes/rebuild services or could I undertake it myself? I could swear there was a thread here about DIY PVS14 rebuilding but I can't seem to find it.

Lots of questions here and for the most part the answer is it depends... Your tube is most likely a B grade ITT commercial tube. I don't think SELA tubes would allow those kind of blemishes but who knows. Let us add up the cost here. $300 for single battery housing, $1800 to $2200 for new tube with warranty. We will split the difference and just call it $2300 to upgrade your existing unit.

Your tube has used value as a beater (roughly $500 to $600). So we have a net cost to you of roughly $1800 assuming you do the work yourself although I am sure if you bought a tube and lower housing from a dealer they would give you a really good deal on the install if not do it for free. Where can you buy a new autogating 14 for $1800 ? Yes this is the way to go and if you learn some skills you can even do it cheaper. I have good experience buying used tubes but this is an extreme gamble if you don't know what you are doing.

Call TNVC and I am sure you can get some quotes on tubes. They have a wide variety to suit your needs. Your old tube is most likely around  Omni IV performance. You will see a very noticeable improvement with a new model autogating tube. The L3 Omni VIII tubes are very nice and the ITT offerings are nice as well. TNVC even has some other commercial tubes that in my experience performed really well. Give them a call to discuss your options.

Another option is to just sell your scope as is and use that money for an new unit. I would estimate its value at $1500 to $1800. Hard to say because I have seen folks pay a lot of money for old gear on eBay. They usually have no idea what they are bidding on.