So today i moved my wifi to channel 6 (from 11) as otherwise 11 was quiet. I then moved zigbee to 25 in the hope it would have less interference. But although the lqi value is consistently 255 (improved from channel 15) I get worse rssi (high 80s) and the zigbee devices in garage are not visible. Will move back to 15.
I also have an xbee on order.
Is there any value in the turning the hub off for 15 mins first?
RSSI values should be negative numbers. That's why -90 is a weaker signal strength than -40. Signal strength is represented in -dBm format (0 to -100). This is the power ratio in decibels (dB) of the measured power referenced to one milliwatt.
Generally, anything -60 and above ( meaning -50, -40, etc.) would be considered a very strong signal. -75 is usually OK for zigbee home automation transmissions.
Anything at -80 and below ( meaning -85, -90, etc.) is mostly noise and you risk losing messages, but as @patrick mentioned, a good LQI would improve the quality somewhat even at the lower RSSI levels.
(Note that there is no IEEE standard for LQI: different manufacturers range it and calculate it differently. For example, Ember uses positive display numbers for LQI where higher is better: they display a zero error rate as a 255 LQI value, and a three error rate (worse) as a 63 LQI value. But other manufacturers handle this differently. )
And some devices, specifically battery powered devices regulate their power output to conserve battery life. This can result in changes in RSSI depending on radio power state and activity. For example, on join / pairing mode, devices typically run at full power to make sure they can see the neighbor. But can and will then drop to a lower power mode if it sees that its signal strength and quality is good.
That makes a lot of sense, thanks for correction.
I tried 25,22,20 and all seem to result in rssi values in the mid -70s, but not able to see the devices in garage. I went back to channel 15 and I can see them but fear for drop outs. I do not understand why this channel is better when it sits between the busiest Wi-Fi channels.
Anyway will stick with this until xbee arrives. Thanks for all the input.
As a reference, some devices does not accept the channel change immediately, some must be re paired, in the next update some fix for that is coming but not every device changes the channel without any human interaction(reset). I suspect you have a couple of devices in the garage that they are not changing. Wait for your Xbee, test on the same channel 15.
Hi vjv, I have been mostly focused on the samsung outlets which I can get to force the channel change by holding down the button whilst turning on power. Actually once these are connected everything else comes to life very quickly.
2 xbee installed, one in garage and one in house, seems to work a treat. Rssi is -74 and switches in garage have been reliable so far.
I ended up getting some xbee2 units from mouser and usb adapters off amazon.
Configured as OP and worked straight away. Although it's a bit odd as the xbee never seemed to complete pairing with hubitat, but after initialization they seem to be working and doing the job.
As a bonus i no longer need 2 of the the switches that were used as repeaters, more automation opportunities lurk.
are these xbees hard to implement? Are they as easy as any other zigbee device or do they need programmed?
They're somewhat involved: Everything Xbee
I'm intrigued myself. I think the only thing it relies on is a custom driver. So as long as that stays playing nice with the hub, the zigbee mesh should stay solid.
What is this custom driver you speak of? I'm not using a custom driver, but did ask elsewhere for one. Care to share??
Sorry, I don't know much about it. In that thread there is talk about using/wanting/needing a custom driver for the XBee if you'd like to check it out.
I did not need any driver infact the device pairing never got beyond initialization so I have no device on the hub anyway. I have seen some oddly named devices in the zigbee logs. As long as the xbee has attempted to pair it seems to be able to take care of itself.
It took all of 10 minutes, hardest part was the sourcing one. Mouser have xbee2s available, which seem to do the job. It's also intriguing to watch the mapping happening when xbee scans your network and is connected via the xctu software. So far i would recommend if you have zigbee issues.
regarding lower power rating on channel 26
"FCC regulations mandate lower power levels on channel 26, so if you fix your network to channel 26,
you will experience significantly less range on the devices."
here as well channel 26 low power
(may not apply to devices that are not US certified)
you can also analyze your signal strength and channel noise using an Xbee and XCTU sw
I use zigbee channel 20
note: for Xbee and XCTU sw they are in hex so will be listed as channel 14 (channel 20)
Prior to having an Xbee I went through each and every channel one at a time with 3-4 different hard to pair devices several times over to determine which channel worked best for me.
no driver is required for an Xbee to work as a router for other devices,
it will simply appear as a "device" in the Hubitat device list.
It maybe possible to create one for an Xbee3 in the future.
Hi. Could someone point me at some simple instructions please for how to build an xbee zigbee repeater that will work with xiaomi sensors? I realise that there are many buying options, but if anyone has a list of devices that work and how to setup and configure I'd really appreciate it. Looking for a step by step guide for the uninitiated 
thanks
Thanks for that. Looks good. I just priced this up and it comes to just over $100 NZD.
A new Hubitat Elevation hub would cost less or around the same price. Do you think if I am looking at extending the range of my zigbee network for Xiaomi devices I would be better off getting another HE hub?
thanks
Should be more like 35 USD. and if it does cost 100 NZD, go for the 2nd hub instead. you'll get much much greater all around capability.
Download the Hubitat app
