Oceanic Transmitter Calibration Ins and Outs

[Knockout Diver]

Short back story: I bought this Oceanic DataTrans GDI2 a few years ago right before I moved to Oregon and I never got to use it up there. Then I found my way back to Texas and decided to dust off the old gear. Got it all serviced except for the watch and transmitter but I changed the battery in both of those. I put my watch through a pressure chamber and it worked great. I hooked up my Oceanic transmitter to the first stage, turned on the valve, it connected... but the PSI on the watch seemed to be slightly off. So I hooked up my HP splitter and sure enough, the gauge is reading about 200 PSI more. By this time I bought an Oceanic Atom 3.1 (darn you eBay!!!) with a transmitter. Hooked that transmitter up and it's reading the same as the gauge. Opened up the transmitter, everything seems to be correct, nice and clean. Nothing broken or rusted. Hooked it back up, still 200ish off.

The question: Anyone know how to calibrate an Oceanic Transmitter? What exactly does it transmit? Just PSI? PSI and depth?

PS: anyone want to buy a GDI2 and Transmitter? If not, it's going into my bag as a backup.

 

[scubadada]

No calibration. The Data Trans or Data Trans Plus are about 20 years old. Good thing it still works. PPS has had this transmitter since 1995. Who knows what pressures are correct. The 200 psi differential is probably not that important for most situations. Both my transmitters are right on my SPG but are a bit higher than an old SPG.

 

[Knockout Diver]

Thank you! I thought the coil on the inside would have something to do with it but didn't want to mess with it until I heard something.

 

[Tbar]

What's the variance between SPG and new transponder at around 500psi tank pressure?

 

[Knockout Diver]

Good question. I haven't taken my tank that low as air fills are a shore around here.

 

[brtlmj]

Thank you! I thought the coil on the inside would have something to do with it but didn't want to mess with it until I heard something.

By "the coil", do you mean the one with a ferrite core that surrounds the battery compartment? Because I am pretty sure that this is an antenna

B.