Which antenna is the Z-Wave one?
The one closest to the USB power port. If you are looking for a different z-wave antenna, I would recommend this one from L-com:
https://www.l-com.com/wireless-antenna-900-mhz-3-dbi-rubber-duck-antenna-rp-sma-plug-connector
I've used these antennas on a C-7, several C-8 hubs, and now on two C-8 Pro hubs.
5 Likes
Do they make a noticeable difference?
And do you replace both of them, or just the z-wave antenna?
I just replaced Zwave one. Noticed improvement right away.
1 Like
The recommended antenna is tuned for the 900 Mhz band. Thus, it will work well for Z-wave. The Zigbee antenna operates in the 2.4 GHz band. You can get a replacement antenna tuned for the 2.4 GHz band (WiFI, Bluetoth, Zigbee), but it is probably not needed as Zigbee works well with a repeater mesh.
Also remember that the higher the gain on an antenna, the more directional it becomes. So highf gain is not always an advantage,
2 Likes
I feel like I've maybe asked you this in the past, but did you also replace your zigbee antenna?
If so, do you have a link for what you like for that one? Many thanks!
1 Like
I replaced both of mine, basically moved my antenna mod C7 antennas to my C8 Pro. Here is the recommended Zigbee one:
https://www.l-com.com/wireless-antenna-24-ghz-5-dbi-rubber-duck-antenna-rp-sma-plug-connector
And be careful with the higher gain Zwave antenna. I had originally had the higher gain one on my C7 and when I migrated to the C8 Pro and moved antennas too I had inclusion and exclusion issues. See this post:
2 Likes
Right on, thanks... 3 dbi seems to be an all-around confident choice for ZW, but I'm less sure about the dbi to try for ZB...
For my own ZB mesh here, I have best results with radio power = 4 since I have a very robust mesh of good ZB repeaters that carry all the water.
So I'm leaning toward trying an L-Com 3 dbi on that one too... But I am the furthest thing from being an RF expert, so I'm admittedly just bumbling around here.
For comparison's sake, do we know what dbi the stock antennas are?
2 Likes
I use the same one that @ritchierich uses for ZB. Both the L-com antennas have worked well for me as well.
I do have a 9 dBi L-com Z-Wave antenna that I used with my C-7. After @ritchierich's experience, I tried using that with a C-8 that I've setup elsewhere. Everything was fine for an hour or two, but nothing worked later on that day. Switching to the factory antenna fixed it (even without a reboot). I now have a 3 dBi L-com z-wave antenna installed on the C-8 as well.
2 Likes
Z-Wave there's a noticeable difference. More devices joined directly to the controller, and in general, the mesh is way more responsive.
ZIgbee - harder to say.
I did replace both. At least in my system, the z-wave replacement produced a noticeable positive difference,
5 Likes
Yes. I believe they are 0.8 or 0.9 dBi. I will get the real number later on today.
@johnwill1 posted this from the C-8 FCC filing:
2 Likes
My external Z-Wave atenna experience has been different, no idea why...I'm using a 7dBi Binfu Z-Wave antenna on my C8-Pro (and C8 before that) w/out issue. Devices join and exclude easily, operate normally, most of my Z-Wave are paired directly to the hub.
Not sure why I'm an exception to the "too many dBi" issue that others are running into. I haven't had problems so I've stuck w/it under the "If it ain't broke" rule...but if someone was going to make a change I'd definitely recommend what @aaiyar uses/recommends.
5 Likes
Higher gain may work against you in a multilevel home because it flattens the "doughnut" radiation patterns. The stock duckies are dual band. Why it does not matter where they go.
3 Likes
Just a quick note. When they advertise an antenna as a certain dBi it’s usually the highest gain at a specific frequency. But since most of them do function at 900 and up in the ghz, you really have to look at the gain graphs to tell how it’s going to function for zwave or zigbee.
2 Likes
