Identify apeks second stage

[scubaalblake]

I have 4 apeks regs…..ATX40, TX40, TX50.
second stages are all pretty much the same and I am very familiar with the internals.
just picked up a DST with two second stages from eBay.
ebay ad said ‘just serviced’ but looking at the filter it hadnt been done for years (which I expected)
i have serviced the first stage and one of the second stages for my oxygen reg - all good.

the other second stage is a little ‘weird’.
all my other apeks second stages have a valve spindle where the adjuster screws to the inside of the spindle.
this second stage has a plastic adjuster that screws down the outside of the spindle itself.
it has a TX50 cover - but is different to the others I have.
it might be a TX50 - but if so it has different internals to the others I have.
it’s definitely old. Does anyone knows what it might be?

pictures of the spindle attached so you can see what I mean.
cheers

 

[axxel57]

I have 4 apeks regs…..ATX40, TX40, TX50.
second stages are all pretty much the same and I am very familiar with the internals.
just picked up a DST with two second stages from eBay.
ebay ad said ‘just serviced’ but looking at the filter it hadnt been done for years (which I expected)
i have serviced the first stage and one of the second stages for my oxygen reg - all good.

the other second stage is a little ‘weird’.
all my other apeks second stages have a valve spindle where the adjuster screws to the inside of the spindle.
this second stage has a plastic adjuster that screws down the outside of the spindle itself.
it has a TX50 cover - but is different to the others I have.
it might be a TX50 - but if so it has different internals to the others I have.
it’s definitely old. Does anyone knows what it might be?

pictures of the spindle attached so you can see what I mean.
cheers

I guess it's a pretty old version of the TX40......., but I'm not extremely familiar with the Apeks Regs.

 

[tbone1004]

non adjustable version, so basically a TX40. It may be a T40, AT40, etc. but it doesn't really matter as the guts should be the same. You can convert it to adjustable, but most don't bother.

 

[Jimchris]

I just had a couple of these on the bench for service, back when Apeks was building regulators for Zeagle. Is the diaphragm in good shape? Most of the Apeks 2nd stages from this era that I've come across, the diaphragms needed replacement due to being very warped.

 

[Centrals]

The adjusting screw is completely different from my ancient T20 and TX40.

Apeks 2nd stage adjust screw

Apeks 2nd stage adjust screw

jonasdive.com

Apeks rarely changes the design of the part.

Could be DIY.