I always wanted to put my hub in my server rack with my other equipment instead of it being hung up on a wall (Had to be wall hung for optimal coverage) But with the C8 replaceable external antennas I went in search of new antennas that would work. So looking at all the specs of ZigBee and Z-Wave and what was needed and the connector type and knowing I needed them to have 5-10ft leads on them I found some.
I did some basic testing ahead of time (Basic because I did not want to buy an analyzer for them). The hub was currently on the ground level on the upper part of my wall. So, for the testing I proceeded to get n ZigBee and a Z-Wave device and headed outside to the corner of my property. From them I proceeded to add each device to habitat from where I was standing and then made sure they responded once paired. Which they did, I continued to do this test for all 4 corners of my property with removing the device before each test. They all worked. (Except in my tin shed I wanted to test if that would work inside, it was very unresponsive once paired)
Next, I took the hub down in my basement to my server rack (Which is next to my furnace and concrete walls, but just placed the unit about where my replacement antennas would go. (Not inside rack yet) and did the same tests as above. Devices would not connect to hub except from one corner of the property. So, I defiantly needed new antennas if this was going to work.
I order the antennas listed below as they meet all the requirements needed at least on paper. So, they arrived today and I proceeded to replace them on the hub without issue, put them in about the same spot as the hub was down by my rack and put the hub itself in the rack, then did the same tests as above. Well, they worked great, better than expected. I could connect to the hub from all location including inside my tin shed now. And I could go beyond my property also not that I needed to.
Glad it worked out for you. Higher dbi means it reaches a further distance but at a cost of smaller side coverage. I too have been playing around with several antennas.
I expected phenomenally worse. Remarkably worse doesn’t seem as bad. Kidding aside; I swapped the stock antenna for the L-Com Zigbee antenna recommended by some for the previous hub’s antenna mod and watched what happened in the route table. I didn’t see much of a difference. LQI was slightly lower for some devices and slightly higher for others. Definitely not something I would recommend. I then put the stock antenna back on and the L-Com one back in the drawer.
Anyone know if there is a way to obtain a replacement stock antenna for the C8? I broke one of my antennas (the circuit board snapped in two pieces). I swapped the front intact antenna attached to the zigbee port for the broken back z wave antenna since most of my devices are z wave, which leaves my system 95% functional. Hubitat support simply replied "Thanks for taking the time to reach out to us. We have reviewed your case and determined that based on details provided and engineering logs your hub is not dealing with a hardware malfunction of systematic issue", which still leaves me with a non-functional zigbee network. I can't figure out another way to contact support, and don't know where else to search for an equivalent antenna. Thanks for any help from someone out there...
Thanks, I messaged @support_team. Since I don't have a lot of technical knowledge on the subject, I wouldn't even know what to look for in an antenna, if I had to buy it on my own. The C8 was able to connect to the majority of my z wave devices directly, as compared to the C7, so the stock antenna seems fine to me. I'll wait to hear from support before purchasing something from Amazon or Ebay.
But I agree w/starting w/Support to see what they can do for you. If that goes nowhere, the antenna I posted a link for has worked well for two of us so far, and I believe it would also work well for you.
You could always reply to the email and provide additional details to your case. Perhaps you selected a radio being offline, which was not observed based on your hub's engineering logs, thus the response you received. You could also provide the additional details via private message, since you are here, in the community, as you already did.
I tried them pointing parallel to my home's main N-S axis and at 90 degrees. I gave them each over 2 weeks in each direction and I'm still worse off than the C-7. Below is a link where I posted a screenshot of my charts showing how many are are 100, 40, 9.6 and how many are faster, slower or the same:
BTW, 2 of the faster ones, my (Stuart's) upper and lower hutch lights are plugs that sit right below the C-8. But, at the same time, my Fibaro KeyFob is in that same room and only a couple of feet further away from the hub, but it is slower than before. So go figure.
One thing to note is that virtually all of my devices are in metal boxes, that I can't change, as I live in a condo, but some aren't, such as the free standing Fibaro Key Fob and the Palm Room Table Lamp Plug. While the devices connecting at 100, 40, and 9.6 varies from day to day, on only 1 day since mid-April when I installed the C-8 did I see any improvement over the C-7. Below is my slower/faster devices as of this morning.
As I've also read that sometimes the lesser powered ones can perform better. But, before I pull the trigger on either of those I'd like your opinion on whether you think I should try to go with the bigger or smaller one, or if it even matters at this point.
Any ideas why I'm getting consistently worse performance from the C-8 vs. the C-7?
Are you sure you don't have a ghost device messing up your mesh? This does not look like an antenna issue, but rather a mesh issue.
Generally speaking, changing the antenna is not going to improve anything, and more likely will make it worse. The radio's power is constant. All the antenna does is shape the signal. A higher gain antenna may create a shape which delivers a weaker signal to your devices, depending on the physical layout of your devices.
Here is my floorpan. The hub sits on top of a mostly wood cabinet in Bedroom 2 right by the wall between the bedroom and the Master Bedroom. The room in the lower left with no label is the Palm Room and the Den/Exercise room is the Wegitorium. The Dining room takes up about 1/2 the distance shown and the other 1/2 (ending with the wall to Bedroom 2) is the Family Room (also called the Living Room). BTW, the floorpan shows a closet between the living room and Bedroom 2, but it is really 90 degrees from there on the wall by the 3rd bathroom.
