"AB-915" amp for improved range

I’ve been testing the device linked below and had really positive results. Claims up to 10 db TX increase and 11 db RX, both of which seem to be accurate based on my testing. It automatically switches between RX/TX and does actually improve reception, picking up some messages weaker than -150 dbm that could not be received with the same antenna attached directly to a Heltec node.

Most impressive is the TX range increase (to be expected I suppose going from about 20 dbm to 30 dbm.) It filled in a bunch of dead spots in my area. I also tested on the Helium network boosting a 20 dbm device. Packets sent through the same roof mounted antenna hit 25 hotspots with an average distance of 4.5 km and max distance of 8 km without the amp. With the amp it reached 59 hotspots at an average distance of 7.5 km and max 23 km.

It’s also extremely low power consumption… ~8 ma idle, 15 ma RX, 650 ma TX. Easy to run off a small power bank for an extended period of time in a portable application.

$60-70 seems a bit steep but I imagine prices will come down since there’s a ton of these on the market without much demand.

https://www.walmart.com/ip/SIGuang-915MHz-AMP-Bias-tee-For-Lora-Signal-Extender-for-Helium-Amplifier/1565268269?athbdg=L1100

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I looked at the device via the supplied link. What is the IP rating and temperature range. This would be ideal for a router application mounted on a mast with a T-Beam. It would be in an enclosure but the enclosure would be at top of the mast in the elements. Thanks!

It’s just an aluminum case without any sealing around the power/radio ports, so zero moisture resistance as is. I wondered the same about temperature rating but couldn’t find anything. It’s the same description on ali, ebay, Amazon, etc.

AMC 2,

Thanks for the reply. I hope to get 12 miles to another mountain top line of site. I will try this if I can’t reach it. Was hoping to use an omni antenna but might have to get a Yagi for that frequency.
Thanks again!

K8TFG
Duff Kindt
High Efficiency Products

With LOS to a mountain top, you should have no problem connecting at 12 miles using an omni without an amp. It would probably even do it with a stubby antenna on both ends. The amp really helps push through if there are obstructions or in near-LOS conditions.