Hello all,

Last week I took the first step toward upgrading my current kit after finding a very good deal on a Nauticam A1 / A7S III compatible housing, which will eventually house a Sony A7S III as my primary video camera.

The housing is almost new. It has only been in the water three times and was originally purchased for a project that did not go ahead. It was tested, then put into storage for nearly five years.

So far, so good.

However, when I tested the moisture alarm circuit with a damp Q-tip, the buzzer did not sound. The LED switches from blue to red and requires a reset, but there is no audible alarm at all.
I initially suspected a low battery, so I replaced it with a brand new Panasonic cell, but the result was the same, none of that high pitched squeal we're hardwired to fear, a world of silence...

I trust the person I bought it from and do not believe the housing has ever been flooded. There are also no visible signs of corrosion anywhere inside. My assumption is that this may be related to the long storage period something having degraded or come loose.

I'm wondering whether others here have experienced failed or dead buzzers in Nauticam moisture alarm circuits, and whether there are any meaningful tests or troubleshooting steps I can perform before replacing the circuit entirely.

At this stage, I assume the whole circuit will need to be replaced if the buzzer itself cannot be isolated and repaired.

Thanks in advance for any insight.

Cheers!

Ben

Edited 8 hours ago8 hr by bghazzal

First thing I would try is a multimeter to see if voltage is applied to the buzzer when it activates. It could either be the buzzer itself or the relay/transistor inside the electronics box that is not switching voltage to the buzzer. I assume the vacuum system is working, I expect the buzzer could be replaced if you had enough electronics experience to work out what type it is a select an appropriate replacment.

Something like this would likely work, but you would need to check the voltage applied, I expect it would likely apply direct battery voltage.

https://www.jaycar.com.au/mini-pcb-mount-buzzer-9-14vdc/p/AB3459

as you can see it's a $5 retail part.

Buzzer is more annoying than useful. Personally, i would just use it as is if simple measures can't fix it.