Shearwater Perdix AI

[scubadada]

So - what is the sampling time frame on the Perdix? I can't seem to find it - 2 secs, 5 secs, 10 secs, 30 secs? I down loaded my first dive and realized I did not set a sampling so it must be standard and I can not find it in the operating instructions.

That's interesting, I could not find it in the Perdix AI manual either. My Oceanic computers offer 2, 15, 30, and 60 seconds. I use 30 seconds, dive resolution is adequate for me. If the Perdix log gives dive details in a tabular form, you may be able to determine the sampling rate by checking how many data points are available each minute. From my VT3 log, you can see that there are two data points per minute.

Let us know what you find out

 

[Basking Ridge Diver]

Let us know what you find out

10 sec increments. But you need to follow the dive line to figure it out. It is not broken out like OceanLog where you can cleanly see the Elapsed Dive Time.

 

[Joneill]

10 sec increments. But you need to follow the dive line to figure it out. It is not broken out like OceanLog where you can cleanly see the Elapsed Dive Time.

Section 4.2 of the Perdix AI manual states: "Pressure data is transmitted every 5 seconds.". So data is sent every 5 seconds, but not sure how often it logs a data point.

 

[scubadada]

Section 4.2 of the Perdix AI manual clearly states:

"Pressure data is transmitted every 5 seconds."

I'm not sure that is the sampling rate for all dive data. Pressure data for my Oceanic is transmitted much more frequently than the 30 second sampling rate I've chosen for logging dive data

 

[Basking Ridge Diver]

Section 4.2 of the Perdix AI manual states: "Pressure data is transmitted every 5 seconds.". So data is sent every 5 seconds, but not sure how often it logs a data point.

I believe this is for your tank pressure only - Air Integrated display on your computer during your dive. But the sampling of all data for your dive is every 10 seconds.

 

[Joneill]

I believe this is for your tank pressure only - Air Integrated display on your computer during your dive. But the sampling of all data for your dive is every 10 seconds.

Yes, that is transmitter send frequency. I don't see the logging rate specified in the manuals - maybe timestamps (if visible) in the log data (on computer or desktop app) give a clue? I'll have to check.

 

[Joneill]

I believe this is for your tank pressure only - Air Integrated display on your computer during your dive. But the sampling of all data for your dive is every 10 seconds.

I checked the Shearwater Desktop log and, as you indicated, the data points on the graph are displayed at 10 second intervals.

 

[Texas Torpedo]

I checked the Shearwater Desktop log and, as you indicated, the data points on the graph are displayed at 10 second intervals.

Sure would be nice if this were user adjustable. I prefer a higher resolution even if it might reduce the # of dives stored in the Perdix, and if it affected battery life..

 

[travlbum]

I have the Perdix AI and have put around 50 dives on it.

Pros: having GTR and SAC in realtime during the dive is *amazing*. 100% worth the price of admission. About 6 dives after installing my transmitter my SPG broke and started freeflowing. Haven't had a change to replace it and at this point I don't think I will.

Cons: the design of the transmitter is horrible - it looks too similar to the valve on the tank. Twice already helpful people have twisted my transmitter and blown the first stage open. I'm going to spray paint the transmitter and put a wrench and more o-rings in my travel bag.

Overall, AI is now 100% a permanent part of my gear. I probably won't use an SPG. I can't think of anything worse than just having to surface with a safety stop if things fail. At this point adding an SPG just adds another point of failure. If the transmitter goes underwater or the battery dies in my computer, these are not life threatening situations. Hell, as long as air isn't leaking I'm not even sure it'd cause me to abort the dive.

 

[The Chairman]

it looks too similar to the valve on the tank.

Point it in the other direction, where you used to have your SPG. I never had that problem and would slap anyone who screwed with my gear like that.