Experience with Same Colored Transmitters

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rob.mwpropane

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So I've been running 2 grey transmitters for a while and had yet to have any interference until this past Monday. I would have thought that they would have just dropped out, but that's not at all what happened. It started with one "no comms" flashing on one but between the flash would be the psi from that tank. Now the psi might have just been the last known psi I'm not sure. At first I thought maybe it had just lost comms so I held the perdix closer and that did nothing. I didn't really care and went on and then both dropped out. Same thing, no comms, but in between the blink there would be the psi, but not always. Honestly it acted more like a computer having a meltdown, acting very quirky. Not the dc itself, just those 2 slots on the screen. Sometimes the blink was yellow, sometimes red. Sometimes there would be a psi between and sometimes not. It finally dawned on me what was happening and to remedy I had to shut one tank off, purge, counted to some # like 4 and turned back on. All was fine after that.

Very odd, it had worked fine for the 1st 15 min or so and then went haywire mid dive. Did not happen again.

Just sharing my experience, I know you're not supposed to run 2 of the same color but Idc... the grey ones always seem to go for cheaper. Hopefully this helps someone.
 
The intervals between transmissions for the same-color transmitters is nominally the same, but due to slight variations in components they will have slightly different intervals. Depending on how close in time they are initially pressurized, and how different the intervals are, you can get the transmissions "drifting" into overlap. That seems to be what happend to you, with them either completely, or partially, interfering with each-others transmissions. Given some time, they will likely drift apart again, but the difference in interval will determine how fast.

Purge and restart one was a good option! Good practice would be to pressurize regs a few seconds apart initially.
 
The intervals between transmissions for the same-color transmitters is nominally the same, but due to slight variations in components they will have slightly different intervals. Depending on how close in time they are initially pressurized, and how different the intervals are, you can get the transmissions "drifting" into overlap. That seems to be what happend to you, with them either completely, or partially, interfering with each-others transmissions. Given some time, they will likely drift apart again, but the difference in interval will determine how fast.

Purge and restart one was a good option! Good practice would be to pressurize regs a few seconds apart initially.
I never really time it, but I've done a good bit of diving over the last few months and it's the 1st time I've ever had issues. Because I haven't experienced it, it really caught me off guard for a second. My 1st thought was it might be time to send the dc in for service! Easy fix (as long as you're comfortable turning tanks off @ depth).

I would have preferred to have worked that out in the quarry though, LOL.
 

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