Ampilifier shorting out?

[ShimmerNZ]

Hi all,

After a few years of untroubled reporting on Auckland - East I'm starting to have problems with my unit. It seems that it's shorting out some how. The symptoms are it will be running fine for a few minutes then all of a sudden the lights on the main controller will dim down to just 2 red lights and I can see the power light dim on my usb hub. At this point the controller is unresponsive. If I pull out the rj45 cable to the amplifier it springs back to life. I can plug it back in and sometimes it dim straight away other times it will work fine for 10-15 mins and then the same will happen.

I've pulled apart the casing on the external amp and verified that it's still weather tight (it is). Checked over all the solder joints, tried it with a different cable but the results are the same. The only observation I've been able to make is if I pull slight on the rj45 into the amp I can sometimes simulate the behavior. I've cleaned out the terminal and this morning applied some hot glue around the outside to hold the cable in the connector to see if that fixes it.

Other than that starting to be at a loss for what I can check. Any thoughts on where else to troubleshoot?

cheers,

Mike

[tgsnoopy]

Check carefully moving left & right the cable going into the crimped plugs on the UTP cable, it might be shorting out in the plug. Re crimping a new plug should sort that. Otherwise I'd be looking sideways at the electrolytic capacitors on the amplifier board.

Without looking at a schematic, they would be my two best guesses.

[ShimmerNZ]

bugger... it lasted a few hours this time before the same occurred so guess it's not a loose connection. I tried with a different cable and was able to replicate the issue so am sure it's not the plug.

I'll replace the caps tomorrow and see if that makes a difference.

[tgsnoopy]

Do you have a different PSU you can try? Would be a downer if you did the caps and later found a faulty power source.

[ShimmerNZ]

yeah tried straight into pc, via powered usb hub and via battery pack with same results.

I've replaced the 440uF caps to start with as didn't have any 2.2uF handy. So far it's been running ok for an hour. I'll give it the rest of the day before I reassemble and put back outside otherwise it maybe a trip to jaycar

[ShimmerNZ]

damn it and that failed too. Have picked up some 2.2uF's and replaced them as well. It annoys the snot out of me that it's intermittent.

When it failed, I tried powering it directly via the mini usb plug rather than power over rj45 and it had the same issue, so almost certain I'm troubleshooting the right component.

I've put her back up outside now, so given I've tempted fate it will no doubt fail anytime soon now.

Maybe time to replace with system blue.

[ShimmerNZ]

ended up replacing with a system blue soon after buying it I managed to find the issue. I'll order some more ferrite roads and see if I can find the red a new home.

[readbueno]

Come on! I am dying to know what the problem was and how you fixed it.
Did you get a Blue? Did the Red Station find a new home?
Did the cobblers apprentice marry the Princess?
Did they all live happily ever after?
Inquiring minds want to Know!
Best wishes,

Brian.

[ShimmerNZ]

Sorry it's been a while since I've been on here but to answer your questions....
Fault was the board mounted rj45 component any sideways movement on it was enough to cause a short.
Yes I ended up getting a system blue which has been running even better than my red. The red hasn't found a new home it's still in my office. I had it running side by side for a comparison for a while and was intending to try out some different ferrite rods. I made some and purchased some different rods, but never got round to actually trying them out. For now it hasn't got a new home.
The Princess unfortunately was crushed by a falling tree so never had the chance to marry the apprentice. After 3 months of mourning he moved on and is now dating the Bakers niece.

late edit: it's alive again and mounted on top of the pool shed and returning results (though pretty crappy ones at the mo)

[ShimmerNZ]

zip tip holding rj45 component down to stop shorting was never a good fix, so 6 years later I desolder and replaced the rj45 port and she's properly back online, now to fix system blue thats lost gps