Experience with underwater modems

[MattHixson]

I’m interested in hearing real world experience using underwater acoustic modems. I’m interested in Blue Robotics’ modem and any other third party hardware you might have experience with.
In my application I’m primarily interested in the greatest range for sending commands moreso than a high data transmission speed.
Would love to hear about your experiences.
Thanks,
-Matt

[EliotBR (Eliot)]

Hi @MattHixson, welcome to the forum

I don’t have personal experience with acoustic modems unfortunately, but hopefully some community members can chime in with their experiences.

@MattHixson

I’m interested in Blue Robotics’ modem

We don’t make our own, but we’ve partnered with Water Linked to sell their M64 Acoustic Modem (link to our product page, with technical details), and there’s a post describing its setup and usage here:

Water Linked M64 Acoustic Modem Testing and Lessons Learned

Hi Everyone, its an exciting day here as we finally have the Water Linked M64 Acoustic Modem in stock! Supply is a bit limited right now, but we have more on the way! Due to the nature of the modems where one is usually mounted underwater and the other one topside, we have opted to not put penetrators or other connectors on the modem wire ends. Based on user feedback, we may change this in the future. Earlier in the week, we tested a pair and wanted to relay our results. Here are some of the t…

[MattHixson]

Thanks, Eliot. I see the peak current on the datasheet of “216 mAh at 12V”. (Shouldn’t that be just mA rather than mAh?)

I’m wondering what the current consumption is when it is listening for a connection.

Thank you,
-Matt

[EliotBR (Eliot)]

@MattHixson

I see the peak current on the datasheet of “216 mAh at 12V”. (Shouldn’t that be just mA rather than mAh?)

Indeed - thanks for pointing that out, I’ve corrected our technical details table.

@MattHixson

I’m wondering what the current consumption is when it is listening for a connection.

I’m not sure if that’s been measured - I’ve asked the Water Linked team if they have data for that. For what it’s worth, the 216 mA value seems to have been calculated from the 2.6 W Power Consumption value in the datasheet (2.6 \text{W} / 12 \text{V} \approx 216\text{mA}), which I’ve now also added to our technical details table.

[EliotBR (Eliot)]

@EliotBR

I’ve asked the Water Linked team if they have data for that.

Following up on this:

@wlkh

The modem has approximately the same power consumption during listening and transmitting (power consumption is slightly higher during initial bootup).