Multiple APs Sync from One SM - Revisited

Products PMP
1

First: If I make a special sync cable that connects multiple APs to a single SM which is repeating sync will the APs receive sync?

Second: I’ve looked at the pin outs and was considering an RS232 hub. Specifically this device:
http://www.rs485.com/pdffiles/multipler … 232hub.pdf
Would that work? If it would work it would allow me to take sync to the ground and back up the tower.


What I am trying to do is put 1 900 MHz AP and 1 2.4 GHz AP on the same tower as 1 5.8 GHz SM without having to incur the additional cost of ANOTHER CMM-Micro at that tower.

Thoughts…

2

Shameless bump …

Anyone who would be kind enough to comment about the above post and their experience with similar setups?

Your thoughts will be appreciated and respected.

Thanks

3

This should work. The timing pulse only travels one way: in this case, from the SM through the sync cable to the AP. It should be possible to sodder a “Y” joint into the sync cable so you can connect two APs back to the same SM.

The only issue would be (according to Moto) using equipment on the same frequency (and you’re not).

I’ve not tried this myself, so this is based on zero experience. But it seems solid.

4
ahull wrote:
This *should* work. The timing pulse only travels one way: in this case, from the SM through the sync cable to the AP. It should be possible to sodder a "Y" joint into the sync cable so you can connect two APs back to the same SM.

The only issue would be (according to Moto) using equipment on the same frequency (and you're not).

I've not tried this myself, so this is based on zero experience. But it seems solid.


Thank you Sir! After two PM's to "Canopy_Support" requesting his thoughts on this matter, I had about given up. Didn't even answer my PM... Sweet.

Your thoughts mirror my own. I'll document my efforts here. I am also looking further into the possibility of using an RS-232 "bridge" as time permits.

-m-
5
  1. You only need to worry about sync for the remote APs (900 & 2.4) if they need to coexist with other nearby APs in the same bands. The 5.7 units don’t need to be sync’ed with the 900 & 2.4.

    2. There are other threads in this forum descibing where installers have successfully daisy-chained the timing output from an SM to more than one co-located AP. There’s certainly a limit to how many will work, but I don’t know what that limit is. The issue will likely be a degraded rise time on the timing pulse; the more APs connected, the slower the rise time, the further out of sync the APs are relative to a CMM-timed AP.

    3. I doubt the RS-232 “bridge” will help you for the same reason as #2 above.
6
Teknix wrote:
1. You only need to worry about sync for the remote APs (900 & 2.4) if they need to coexist with other nearby APs in the same bands. The 5.7 units don't need to be sync'ed with the 900 & 2.4.

2. There are other threads in this forum descibing where installers have successfully daisy-chained the timing output from an SM to more than one co-located AP. There's certainly a limit to how many will work, but I don't know what that limit is. The issue will likely be a degraded rise time on the timing pulse; the more APs connected, the slower the rise time, the further out of sync the APs are relative to a CMM-timed AP.

3. I doubt the RS-232 "bridge" will help you for the same reason as #2 above.


Thanks for the feedback.