# Max Length GigaBit ethernet on Fathom ROV Tether

**URL:** https://discuss.bluerobotics.com/t/max-length-gigabit-ethernet-on-fathom-rov-tether/10801
**Category:** Communication Interfaces
**Created:** [October 14, 2021, 10:25am UTC](https://discuss.bluerobotics.com/t/max-length-gigabit-ethernet-on-fathom-rov-tether/10801 "2021-10-14T10:25:57Z")
**Posts on this page:** 6
**Page:** 1

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### Author: ![yosheli](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/yosheli/32/7938_2.png) [@yosheli](https://discuss.bluerobotics.com/u/yosheli)
#### Post date: [October 14, 2021, 10:25am UTC](https://discuss.bluerobotics.com/t/max-length-gigabit-ethernet-on-fathom-rov-tether/10801/1 "2021-10-14T10:25:57Z")

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Hey there,

I have a customer working on an application that uses the [BotBlox GigaBlox](https://www.botblox.io/products/gigablox-small-gigabit-switch) along with 50 meters of [Fathom ROV Tether](https://bluerobotics.com/store/cables-connectors/cables/fathom-tether-nb-4p-26awg-r2/).

He’s using 50 meters of the tether cable, but doesn’t see a link; It works fine with shorter cables.

This possibly isn’t unexpected, the max range of 1000BASE-T1 is around 100 meters, and the GigaBlox uses connectors that will reduce the signal a bit (tradeoff due to size).

However I’m curious if anyone has tried pumping gigabit ethernet down that tether cable and, if so, what kind of maximum tether lengths they’ve been able to achieve?

Thanks!

Josh

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### Author: ![gcelec](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/gcelec/32/2038_2.png) [@gcelec](https://discuss.bluerobotics.com/u/gcelec)
#### Post date: [October 14, 2021, 5:53pm UTC](https://discuss.bluerobotics.com/t/max-length-gigabit-ethernet-on-fathom-rov-tether/10801/2 "2021-10-14T17:53:19Z")

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I presume you’re not using the Fathom X converters and are using 2 of the twisted pairs in the tether? Do you have an RJ45 connector on the top end? Are the other conductors in the tether being used for anything else?

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### Author: ![Mills52](https://avatars.discourse-cdn.com/v4/letter/m/bb73d2/32.png) [@Mills52](https://discuss.bluerobotics.com/u/Mills52)
#### Post date: [October 22, 2021, 12:00pm UTC](https://discuss.bluerobotics.com/t/max-length-gigabit-ethernet-on-fathom-rov-tether/10801/3 "2021-10-22T12:00:31Z")

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Well the answers I’m looking for would be everything in the last 24hrs with a question mark, but what changed between Rusty’s post and BR’s current straightforward numbers? Things seem to be going backwards. Did BR find that when it was unspooled in water that things got worse? Was the older tether better than the newer tether in terms of bandwidth? All I’m looking for is more information to fill the gaps between these data points, to see how we got from there to here. Maybe it’s just the standard “businesses trying to play it safe to protect themselves and keep customers happy” kind of thing, I can’t tell, just trying to figure it out because what I want to do exceeds the recommendations[.](https://www.myccpay.bid/)

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### Author: ![EliotBR](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/eliotbr/32/6937_2.png) [@EliotBR](https://discuss.bluerobotics.com/u/EliotBR)
#### Post date: [October 22, 2021, 12:11pm UTC](https://discuss.bluerobotics.com/t/max-length-gigabit-ethernet-on-fathom-rov-tether/10801/4 "2021-10-22T12:11:02Z")

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Hi @Mills52, welcome to the forum 🙂

> [@Mills52](#):
>
> Well the answers I’m looking for would be everything in the last 24hrs with a question mark, but what changed between Rusty’s post and BR’s current straightforward numbers?

Not sure what you’re referring to here - did you perhaps respond to the wrong post? If not it would likely be helpful if you can specify what you mean by “Rusty’s post” and also which “straightforward numbers” you’re talking about.

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### Author: ![yosheli](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/yosheli/32/7938_2.png) [@yosheli](https://discuss.bluerobotics.com/u/yosheli)
#### Post date: [October 22, 2021, 5:52pm UTC](https://discuss.bluerobotics.com/t/max-length-gigabit-ethernet-on-fathom-rov-tether/10801/5 "2021-10-22T17:52:01Z")

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Hi all,

Just as a resolution on this, it turned out the customer was using subconn micro circular connectors which are known to not work well with GigaBit connections. Pretty sure our issue is related to that rather than anything tether related, though I can’t confirm that until we test the tether with different connectors.

Thanks,

Josh

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### Author: ![lamhung81](https://avatars.discourse-cdn.com/v4/letter/l/c4cdca/32.png) [@lamhung81](https://discuss.bluerobotics.com/u/lamhung81)
#### Post date: [June 11, 2024, 8:21am UTC](https://discuss.bluerobotics.com/t/max-length-gigabit-ethernet-on-fathom-rov-tether/10801/6 "2024-06-11T08:21:05Z")

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So far what is the max length of GigaBit ethernet on Fathom ROV Tether?  
Did anyone try with 100 m?
