Why? Got my KNOT but the antennas will arrive on another day.
Would like to pre-configure ROS. Is this safe or will the KNOT turn into black smoke?
It is a standard disclaimer, the Ax3 has similar label.
Theory wants that you power a radio only with a load connected to it, be it an actual antenna or a dummy one like (example):
https://hamparts.shop/sma-dummy-load.html?
On low power devices, such as the knot, it is improbable that anything will burn, but you never know.
Please note that IF something will burn, it will be something difficult to troubleshoot and replace, see:
But if they bother spending money to put up a warning, there must be a reason...
If a bottle says "Acid: corrosive," do you stick your finger in it to see if it's true?
Wait a minute....... What @#$!!%&!.... didn't they put a stupid antenna in the box??????????
I wanted to buy it, I thought it had the LTE antenna built in........................
From product page:
- The unit requires external antennas – choose the models that match your environment and customize the KNOT to your specific needs
Of course, I would have read it in detail before buying it, but it makes no sense that it doesn't even have a basic antenna...
Absolutely. Or it could ship with a terminating resistor.
Yep, no antennas included. I found now an old WLAN-antenna and connected this as dummy.
I ordered 8 dBi Bingfu antennas (MTs antennas not available here).
They sould really put a smol, cheapo antenna in the box, instead of the sticker (or a dummy terminator).
I would guess that everyone going to fiddle with devices like the Knot has an unused old AP or router somewhere from which to borrow an antenna.
I don't want to do a detailed search now, but I doubt that an old "2.4 only" or "2.4 and 5" GHz antenna
will be suitable for all the frequencies used in LTE...
I would guess the reason antennas are not included is because knot serves a particular market.
For example farm equipment, delivery trucks, and various mobile fleet that needs GPS tracking and light remote access and mobile connectivity. It would have an external magnetic antennas mounted on the rooftop.
And yes, as @jaclaz has mentioned operating a radio without a load is unsafe for the radio itself.
Use an antenna the matches the frequency of the radio in lab testing, and deploy with an external rooftop mag mount antenna in the field.
I attached an old 2.4GHz antenna because of the sticker. The dedicated LTE-antennas will arrive in a few days. But now I can turn on the KNOT an do all the config stuff without damaging something inside. 
PS: I agree about farm stuff or vehicles etc… who use the KNOT.
But MT says:
And for these usecase they should add at least a smol antenna (I think).
Bet they can add a cheapo China-antenna for a few cent. 
Agreed. IMO, the older KNOT still has advantages... which is a shame. And, given the older KNOT was much slower than LTE Cat4 included in "new KNOTs", some tiny stub antenna at Cat4 still outperform the older KNOTs. And without some antenna it's "horrible unboxing" experience since even I'd assume MikroTik included some antennas since it's not a RouterBOARD product where some integration is required... the KNOT looks "ready to use" if read the product page without any clear advisement "Antennas not included".
I like the design of the new KNOT, but certainly some compromises on features. And, I didn't know about the lack of antenna part until this thread. Like the lack of 2.4Ghz, since if KNOT inside some other equipment it be handy of the "embedded routers" actually could provide Wi-Fi to other components for that equipment's M&C. And lack of USB also limits integration possibilities.
In fact, the only bright spot is MikroTik ran it through PTCRB and AT&T certification, so at least they know how to do that, hopefully, for future LTE/5G devices for North America.
@rextended
I don't think that an antenna needs to be "tuned" to a given frequency to offer some 50 Ohm impedance, and the LTE radio should be low-low power, likely around 200 mW or so, surely below 1 W.
@all
A (good?) question could be whether the LTE radio does anything without a SIM inserted?
Unlike the mentioned Ax3 where not connecting the antennas or a load (because wifi is not used) could still be a risk because an upgrade or another "glitch in the matrix" could accidentally switch the radios on, the LTE radio could be doing nothing without a SIM inserted. Or it is "always on" when not disabled?
When using dummyloads as termination, also make sure that they are specified for the frequency being output. E.g. the dummyload mentioned above has specification “DC to 3GHz” and would be OK for this usage but (maybe) not for a WiFi (5GHz) device.
I recently installed a couple of L11UG-5HaxD devices and as I knew about this issue I connected dummyloads, but for one chain I used a 20dB SMA attenuator good for 5GHz (and on that a small antenna to test the config) and on the other I put a SMA-to-BNC adapter and a BNC dummyload.
But later I noticed that this was from the old 10Mbit ethernet networking and I am worried that this may have killed the transmitter chain by reflecting too much power. And unfortunately the new WiFi drivers no longer show the signal quality for each chain separately.
The warning label is incomplete.
CAUTION
IF YOU POWER ON THE DEVICE WITHOUT AN ANTENNA
YOU WILL LIKELY NOT BE ABLE TO BREED
SO DO YOU FEEL LUCKY PUNK