Zaxcom Nomad - Very low level on input 2

[jeansebastienbg]

I encountered a weird problem on my Nomad. One morning, I wasn't able to get a decent level out of input 2. Even with trim and fader maxed out, I was barely able to get enough level to work with. I was testing with my voice, yelling progressively louder and louder in the mic, and I could see the level going up, and when it was getting close to -8dbfs, the signal was suddenly going very loud and distorted. I tried different cables and mics, same problem. I finished the shoot without using this input, and I performed my regular maintenance on it this morning. I started by opening the Nomad to change the internal battery, I did a factory reset, I updated the firmware, and then I performed the trim calibration procedure. Everything went back to normal for about an hour, and then suddenly, the levels went super low again. I performed trim calibration a second time, but this time I couldn't see the levels "creeping up" during calibration on input 2. When calibration was over, I was able to get a normal level of signal in input 2, but now the preamp is VERY noisy. I hear a very annoying buzz that wasn't there before. My guess is that the calibration was performed when the input experienced the "low level" problem and it compensated by maxing out the trim setting. That's why I can hear the noise from the preamp now. I also guess that by some chance, I "fixed" the problem before the first calibration, either by updating the firmware, or by opening the Nomad. My nomad is now read to ship for repair, but I'm still posting here to see if anyone ever had this problem. I'm also curious on what I did the first time that seemed to have fixed it for an hour!

[Jack Norflus]

Sounds like a hardware issue.

You should email zaxcom support at support@zaxcom.com 

 

[jeansebastienbg]

Thanks, I will try that before shipping it.

[resonate]

Trim calibration has to be done EXACTLY how it says in the manual. you had it working once, (for an hour), so I _think_ there has been some calibration procedure error on your part, i suggest trying it all over again (reset firmware, reset factory defaults, careful trim calibration  - remember that calibration has to be done after the unit has warmed up, etc. it's all in the manual) Good luck! And by all means, do email support.

[jeansebastienbg]

Thanks for your input. I'm pretty sure I performed the trim calibration very precisely and exactly like it was specified in the manual. I waited a good 30 min every time for the preamps to warm up. I already tried a third time this morning just in case. The issue is resolved in the sense that I have a workable level on input 2, but there's a significant amount of noise and it sounds like it's coming from the preamp itself. To be noted, the problem was present before the first trim calibration. Also to be noted, the first time I performed trim calibration, I could see the levels "creeping up" on input 2, as they are supposed to. I could also verify after the procedure that the tone coming in input 2 (line) was at -30dbfs from output 2 (set at -10db in the "output levels" menu), as it is supposed to. The unit then worked fine for an hour, but the problem of low levels came back. I performed trim calibration a second time. This time I could not see the levels "creeping up" on input 2, and I couldn't see them again this morning on the third trim calibration. After both the 2nd and 3rd trim calibrations, the tone level getting in input 2 looks like it's now peaking at -35dbfs instead of -30dbfs. That's why my guess is that I resolved the original issue either by opening up the Nomad to change the internal battery, or by updating the firmware, and that I performed the first trim calibration on a normally operating input. When the problem came back after an hour, I guess I performed a second trim calibration on an abnormally "insensitive" preamp. The procedure probably maxed out the trim setting to compensate and that's why I can hear the preamp now. I'll keep you guys posted!

[Wandering Ear]

I recently had similar symptoms on one of my nomads, it was a hardware issue.

[jeansebastienbg]

Was the repair very expensive if I may?

[Wandering Ear]

I ended up replacing the whole input board since I had an early revision, it was around $350 I think.  Not sure what it would've cost if I just fixed the issue , which for me was on inputs 3&4.

[jeansebastienbg]

Same thing here, they replaced the whole board at a fair price. Turnaround was very quick.