I’m trying to connect 2 force 200s across a distance of about 200-300 meters , there’s a clear line of sight. My subscriber module gets a signal of -25 which is good but my Access point stays at -60. I’ve tried alignment the best I can and swapped out the beams multiple times for different ones , all force 200 emp1000s. It stays the same , what does the mean because I have cambiums in other locations and both subscriber and access points have good signals but in this specific location it stays the same
Hello @Elisha_Mtasa and welcome to the Cambium community!
On the AP or master side is the SM target receive level set to -60?
Yes my SM target receive level is set to -60
The SM target receive level allows the AP to automatically set SM’s to the target uplink RSSI. The default and recommended value is -60.
-25 RSSI is way to strong a signal. Ideally you want your RSSI to probably be around -55 to -60 on both sides. You should probably reduce the TX power on the AP/master side to match the SM/slave side.
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Thank you so much , let me try that and see if I’ll get better speeds
Try setting the SM target receive level to -55, and then try slowly reducing the AP/master’s TX power until it is around -55 and both sides match. You could probably even go to -50 and it will be fine.
So essentially what I want is for both signals to be the same or atleast very close?
I think I’m sorted now , thanks for the help, I got -38 on both sides now and my speeds are better
Really what your goal is, is the highest MODULATIONS, or the percentage of data that is going at the highest Modulations. Generally speaking, that’ll not be the ‘highest signal’ necessarily, because being to loud can be bad also.
I often like to think of the signal as if it was sound. It is NOT sound, but it’s an intuitive way to think about it. If you are in an auditorium and you’re listening to someone speak, you ideally want it loud enough that you don’t have to strain to listen (and loud enough that you don’t have to ask the speaker to slow down) and you want very little background noise, but you DON’T want it so loud that it distorts either.
A person screaming in your ear from 6" away is difficult to understand too… or turn your car stereo up to the top, and if the speakers are overdriven, you can’t understand the lyrics of your song anymore.
So, usually you can get top modulations if your signals are in the -50’s and you’ll also want to make sure both ‘chains’ are nearly identical… a -53 signal could potentially have one chain that is a -54 and the other chain could be a -76 (unlikely, but possible if something is broken or aimed wrong) and those two signals might add up to a -53, but it wouldn’t be nearly as good as having both chains be a -56 each, which would also add up to -53
So - I personally would say that -38 is still too loud. Every 3 dB is TWICE as loud, so the difference from a -53 to a -38 is 32x times louder, so a -38 is into ‘screaming’ territory I think.
BUT - as I said at the top, looking at your MONITOR - PERFORMANCE screen, and seeing what modulations you’re packet are going at, that’s really the key. On Force 200’s, you’ll want to get all your packets going at MCS15 if you can.
ePMP Force 200
MCS15 = -65 dBm (per branch)
MCS15 (64QAM 5/6)
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