Shearwater Sale - $50-300 Off

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Dammit.. you got me
 
?? Please explain.

My mistake. I had incorrectly thought the SWIFT provided better low transmitter battery monitoring on the Shearwater computers. Reading the manuals, I believe I was mistaken. I must have misunderstood something I had read previously. But it looks like SW AI computers will report low transmitter battery levels on both PPS & SWIFT transmitters.

@tursiops … thx for the question as it allowed me to correct an error in my understanding.

I edited my post to strike through the incorrect information.
 
My mistake. I had incorrectly thought the SWIFT provided better low transmitter battery monitoring on the Shearwater computers. Reading the manuals, I believe I was mistaken. I must have misunderstood something I had read previously. But it looks like SW AI computers will report low transmitter battery levels on both PPS & SWIFT transmitters.

@tursiops … thx for the question as it allowed me to correct an error in my understanding.

I edited my post to strike through the incorrect information,
ALL the battery monitoring is done in the transmitter and encoded in the transmitted signal. Since the transmitted signal is the same for all those MH8A transmitters, all the encoded battery info is the same, regardless of the transmitter or the receiving computer. The encoding just gives OK (>2.75V), LOW (2.75V), or CRITICAL (2.5V). See Reading Wireless Air Transmitter using Arduino for the encoding, see the Shearwater manual for the voltage levels associated with the encoding.
 
I did think of one more benefit to the SWIFT over the PPS as I was doing my annual battery replacements. The SWIFT is sealed by 2 o-rings including the electronics and the battery. The PPS battery compartment is a 1 o-ring seal a thus more prone to flood.

One downside to the SWIFT is that it is harder to quickly replace the battery. I really would not try to do in on a boat as you are dealing with 4 small screws and a small hex key. Manageable on a large liveaboard, but not on a typical dive boat. A PPS battery swap is a manageable dive-site emergency service.

Thus with the SWIFT, it is important to pay attention to the transmitter battery warning if you get one. You might also consider proactively changing the battery. As recommended by SW, I replace all of mine once a year and sooner if I get a battery warning.

I also carry a spare transmitter in my boat backpack. If I ever have a transmitter unexpectedly die mid-trip, I would just swap to my backup transmitter.
 
Since we, uh, digressed into battery replacement, what is the recommended replacement schedule for MH8A transmitters? I have about 100 dives on one battery (including some extended time when it was pressurized after the dive). I do have an SPG backup, but the batteries are cheap.
 
Since we, uh, digressed into battery replacement, what is the recommended replacement schedule for MH8A transmitters? I have about 100 dives on one battery (including some extended time when it was pressurized after the dive). I do have an SPG backup, but the batteries are cheap.
300 hrs of transmission is the lifespan of an MH8A transmitter I believe. SW recommends yearly or replacement if you get a low battery warning. I don’t know about other computer manufacturers.
 
Since we, uh, digressed into battery replacement, what is the recommended replacement schedule for MH8A transmitters? I have about 100 dives on one battery (including some extended time when it was pressurized after the dive). I do have an SPG backup, but the batteries are cheap.

"5 years or 300 dive hours"

"In normal usage, the Swift transmitter's battery will last several years. Due to the infrequency of a battery change, we made the choice to go with a user removable cover as it allows for an overall a smaller design. The long period between the first low battery warning (yellow) and last transmission should allow you to complete many dives after the first low battery warning, reducing the urgency of a battery change. The battery should be changed as soon as practical after the first (yellow) battery warning and immediately following a critical (red) low battery warning."
 
"5 years or 300 dive hours"

"In normal usage, the Swift transmitter's battery will last several years. Due to the infrequency of a battery change, we made the choice to go with a user removable cover as it allows for an overall a smaller design. The long period between the first low battery warning (yellow) and last transmission should allow you to complete many dives after the first low battery warning, reducing the urgency of a battery change. The battery should be changed as soon as practical after the first (yellow) battery warning and immediately following a critical (red) low battery warning."
5 years of storage, 300 hrs of use.

Many people just wait for the warning. Since I don’t use a spare SPG, I tend to be more cautious and replace mine annually.

I’m unable to find where I thought I saw SW recommended annual replacement. That may also be something I made up! :dork2:
 
5 years of storage, 300 hrs of use.

Many people just wait for the warning. Since I don’t use a spare SPG, I tend to be more cautious and replace mine annually.

I’m unable to find where I thought I saw SW recommended annual replacement. That may also be something I made up! :dork2:
I say I want to replace them every year. But that turns into the yellow / red warning!
 

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