900mhz install - signal gone

I thought I had read about this problem on the forums before, but I couldn’t find any posts via a search.

Is this a problem that has been seen:

I just had an installer put up a install at about 3/4mile. Initial check before mounting had a -59 power level, 5 jitter, and 1800 RSSI. He mounted it, and by the time he got the cable run, he couldn’t connect. Checked the SM, and in AP eval, the power was between -78 and -85, RSSI 1100, and it would not connect.

He just put up another SM, and its connected up ok.

Do I remember correctly that there was an issue with 900SM’s failing within a few hours after install?


I’ve never personally seen an SM die in that short period of time without some sort of external influence (usually static).

A jitter of 5 worries me though. Perhaps the SM was bad but 5 on the jitter in 1x mode is really bad.

what type of 900 are you using

i would run a spectrum analyzer to see what the radio is seeing on the RF interface.

This particlar AP is a a vertical omni. Only has about 5 other users on it…I don’t think any of them have problems. The SM has a vertical stinger on it.

Most of our customers jitters vary greatly. It’ll be 1, then jump to 10, them jump to 6, and so on and so forth.

We switched this SM out with another one, and so far, so good.

You say the jitter jumps from 1 to 10?

Are you running these SM’s in 2x mode or 1x mode?

I think we have 2x selected in most cases. With the jitter jumping, could this be the unit switching from 1x to 2x?

Could be. You probably have high re-reg too huh?

we were using stingers but quickly found out that they just didn’t work very well had the same kind of problems changed them out problem solved

stingers work great for us up to about 5-6 miles & save money vs buying a reflector not to mention the appearance of the system is 100x better. clear LOS is a must ofc