while in practice could not be relevant, the electronic components are not certified for outdoor use (sx1308 temperature range is 0-70C vs -40-85C for SX1301);
having already added an external antenna by myself, one concern I have is about transmission power going over allowed values. In fact, in “normal” gateways you have a way to set the antenna gain, that is used then to decrease transmission power. On TTIG we do not have this possibility; thus, be careful when adding high-gain antenna.
I Think the TTIG fits also in the case with Housing when you unconnect the power plug. My Antenna comes with Mount brackets include (not on picture). But there are better Antennas on the Market. Last week i purchased Antenna tester N1201SA and see the Antenna is not good for 868MHz, it is only good for 915MHz. I replaced the Antenna with the “Aurel GP 868 Ground Plane Antenne”. The Antenna comes with Cable and BNC Connector, so you need an addition adapter to connect the TTIG.
Changes:
-new Antenna “Aurel GP 868 Ground Plane Antenne”
-better h155 coax cable wit sma and F-Connector
-antennaconnector inside the Housing
-installed the included cover holder
-use Pressure compensation elements
If I understand this right, the TTIG GW has an internal PCB LoRa antenne as well as a UFL LoRa connector on the board.
By connecting an antenna with a pigtail on the UFL of the TTIG, you effectively connect 2 antenna’s in parrallel.
Should not there be a zero ohm part be removed or a pcb-track be cut to disconnect the original pcb-antenna ?
In theory this would result in a better radiation pattern and a more effective radiation of the few milliwatts that are generated. Also the GW should be more sensitive as all the received energy of the external antenna is directed into the LoRa chip and not partly into the pcb-antenna.
This is just an assumption of me because I do not have a TTIG to see what is going on.
Or did I miss the step of removing the internal LoRa antenna that was originally connected to the UFL connector ?
edit: Or maybe this chip does diversity with two antenna inputs and switches to the side which has the best signal ?
The internal antenna is connected to the u.Fl connector on the concentrator board. It is not part of that board. So to connect an external antenna you disconnect the internal one.
(I have done that for a couple of units)
Can I not use the USB port for power instead of the built in power source as described in this guide?
Also, how about putting the hardware on the inside of the house and only feed the antenna cable through the wall? (It would be a good solution for me) of it works.
This is the way I mounted my gateways. They are under the roof and connected with low-loss coaxial cable to the antenna on a mast. You don’t need a high-gain antenna for this, 3-5dBi is sufficient. It is much more important that the antenna is high and free.
That works, I and many other Forumites (as @wolfp above) use an indoor gw, well sheltered and in a benign environment, with an external ant deployment, have even done it with TTIGs. Adding external connection will void warranty but no real issue. Your choice whether you add lightning strike protection to the ant feed or not. Recommend use lowest (ultra low) loss cable you can afford, good connectors - tool tight not finger tight - and keep cable run as short as possible. Get ant as high as poss, though if aligned with e.g. roof structure or a ring beam check for metal content … even high metallic content roofing felt, under roof tiles… as may partially mask signal in that direction in which case I’ve had success dropping slightly below eves/soffit/facia board level to get a more even all around coverage.
Don’t be tempted to go mad with a high gain ant, rather just use a standard 2/3.1dbi ant, allowing any increased gain only to offset connector and cable losses otherwise you may breach Tx PWR regs, as well as risk introducing coverage nulls & notches in wider area, or potential up-tilt or down-tilt to mail beam depending on choice… also if in a cold climate be wary of too cold roof space in winter - self heating should mean ok when running, but restart after power outage may be issue, similarly in hot climates be wary of excess heat! Best check device spec and have some idea of expected temp range…
I think I like to do this too. I got the TTN gateway quite cheap.
I wonder, is there a practical disadvantage compared to other outdoor gateways like base on the Semtech SX1302 gateway module?
There is practically no management of the gateway service. But you could see this as an advantage. I wonder about range and power.
The SX1308 needs more power and is less sensitive -139dBm vs -141 dBm but by the time you’ve got a pre-built outdoor gateway with all the extras that they tend to come with, the power consumption differences aren’t an issue if locally powered and you’ll likely be able to build at least two if not three TTIG-hybrid external gateways for the price of a single outdoor one and then compensate for the mild reduction in sensitivity with two or more gateways strategically positioned.
Just disassemble the TTIG - no need to start drilling holes in it - the case isn’t really built for supporting even a basic stick antenna - so may as well just plug in to the uFl. Don’t run mains to the outside box, it has lots of risks to consider, get a 12V wall-wart and decent cable.
I put them in a proper outdoor IP55 case placed where it is not totally exposed to the elements, a buck convertor to get the 12V to 5.1V and power via the USB. Higher gain antennas have complications with local reception, so a nice simple 3dBi in an SMA connector on the top of the case gets the job done.
Put the TTIG in a plastic takeaway box and put that in a sandwich box if the proper case is a bit of an expense.
Thanks. That sounds good.
The TTN indoor gateway is a very old design. Kind of impressing that it’s still good. I would have thought the new specialized chip will beat it.
