is there a plug and play external antenna for Sagemcom Fast 5688W Gateway

Forgetting the numbers, what is the performance you're receiving for the services you normally use? As an example, are you not able to use Zoom? If you can use video conferencing successfully, then the numbers are irrelevant.

I live in S. Florida. T-Mobile gave me an Arcadyan KVD21 5G gateway that only connects with 3 bars of 4G LTE. I had 800 Mbps with Xfinity before I switched, and have reached the conclusion that I was leaving a LOT of bandwidth on the table. I only get get between 35-70 Mbps depending on the time of day, but having said that, I never have a problem connecting to what I want on the Internet, including Zoom.

The acid test is performance. Judge what you're getting from TMHI not in terms of bandwidth, but in performance. I'm not insinuating that in all cases everything will be hunky dory, but the bandwidth you receive from T-Mobile can really only be judged by reliability and your ability to use Internet services the way you intend. In my opinion, if you look only at the numbers, you are judging TMHI on the wrong criteria.

So what you are saying there is no plug and play outdoor antenna available for the 5688W gateway? Or any other of T-Mobiles gateways. Without taking it apart and connecting to the 4 connections with something like a 4x4 waveform antenna.

I only receive ! bar of 5g signal and still run 3 tvs and 4 devices but you’re paying for much more than you are using, that’s why customers want the highest performance achievable.

I saw something about external antennas today at

https://www.waveform.com/a/b/guides/hotspots/t-mobile-5g-gateway-sagemcom

I have no info on this, just recalled seeing it as I researched opinions on the 5688 here on the site and saw your note. If you have gotten something, let us know how it went?

An Arcadyan was issued to me when I signed up with TM last December. There were performance issues lately, and after some tests TM support authorized a gateway exchange. Received a Sagemcom Fast 5688W at the local store instead. For one thing, it has an on/off button which a plus. I'm getting signal "good" as before and speedtests are ~250 mbps, also comparable to previous readings. Tower's about 1.5 miles with a fairly clear shot.

Thanks I will look into it. Otherwise, The only way to improve signal  between tower and sagecom without disassembling the device is an expensive amplifier that will amplify band 71,as well as the others in the 600mhz range is the WilsonPro 710i or the Cel-Fi quatra 4000i products which may require a transmission agreement with T mobile since they do own the space. Haven't priced them nor know how to make them work.

For now I am also using Starlink as a backup usually at suppertime when the 5g signal seems to fail. When I got the 5g device, I thought I could cancel the $110/month Starlink, but I'll keep them both for now

Wilson Pro 710i definitely overkill for a household!

Yes overkill for sure. However I haven't found any other products to amplify the 600mhz range wirelessly. I guess the only thing to do is open up the device and use the Waveform antenna.

How about the 5G store? ANy happiness there?

No didnt try. Support says they are constantly expanding their capabilities, and told me 60days to see improvement. But im sure many have heard that before. 

Wilson Amplifiers has a possible solution but it's only 4G LTE.  It involves a raised external antenna that captures the signal and sends it to an internal unit that then sends it to the 5688W.  Give them a look.  The reason I didn't try it was because the trees between me and the cell tower are over 100 feet tall (pine, oak, poplar, elm).   I could never erect a safe antenna that would be sturdy and not end up being a lightning rod.   If you only need 20-30 feet to clear the trees, maybe it would work for you.

wilsonamplifiers.com

Thanks! Yeh, a standing outdoor antenna is a target. Given we had a lightning storm just this afternoon!