Orange problem

[spook]

I have an orange micro-terror head that when switched on, the LED flashes every few seconds and when it's connected to the speaker it makes a percussive sound in time with the light flashing (there's no other output). Has anyone else ever encountered anything like this? I'm an electronic engineering student (not a very good one, apparently ) so I could probably repair the issue if I knew what was causing it!

[veryredtomatoes]

It's in the process of going to the Dark side. Soon it will shed that pale skin in favor of the darkness that lies beneath.

[Squirrel]

Can you see if the valve heater stays constantly lit when turned on?

[cbrown]

Have you been using it with a 4 ohm load and high gain/volume settings? Apparently this can overload the output stage and cause it to cut out, maybe the output stage has died.

Is it possible for you to try the amp with a different power supply? That may be the culprit.

The sound you can hear could be a relay engaging. If so, it's possible that either the relay itself is faulty and not switching properly or the thing it's meant to activate is failing to activate. The amp could also be failing to supply the high voltage to the tube. Either way, it's not really serviceable without the circuit diagrams.

[OffYourFace]

Good luck. I hope it's something simple.

The way things are made these days are great for production costs but terrible for reliability. Even on the big, more expensive Orange Amps, PCB replacement is sometimes the only way. (I had to do that with an AD200).

I think the marriage of high voltage and high power Tube amplifiers with SMC is terrible. Hopefully things will get better.

[spook]

Thanks for your replies! I'll have to open it up again to see if there's power getting to the tube heater, there's definitely no power getting to the op-amp IC, though!

[Toogy]

Hi, I'm just curious if you ever got this sorted out? My Orange Micro Terror is has exactly the same symptoms! I tried a new power supply and that didn't help. Anything else I can try? I'm hoping you were able to fix yours!

[fphlat]

Not sure if the OP is still watching this thread, but I ran into the same problem with a Micro Dark (bought it untested from a pawn shop - they said it worked, but didn't have the adapter to show me it was ok, I brought it home and plugged in my Micro Terror adapter and got a flashing power light (every 1/2 second or so and no sound)

Well, since it had no warranty (2nd hand and missing screws, so it's been opened - Orange confirmed there would be no warranty because of these factors even though the amp is not even 10 months old - so I figured I'd take a crack at trying to find the problem - and I did!

It was a BAD DIODE ...

On my Micro Dark, I found that the diode right between the Power Input jack and the Speaker Output jack was a little burnt looking, had split and was therefore useless.
Since the OP has the problem with a Micro Terror (not Micro Dark), I opened my Micro Terror and there is a diode in the same spot, so that part of the circuit was consistent (Note: there's a big glob of translucent goop that covered 1/2 the diode in my Micro Dark, and covers the whole diode in my Micro Terror, so on the Terror it wasn't obvious there's anything there until I got a bright light and looked closely).

The diode in the Micro Dark was a 1N4007 ... I didn't have any at home, so I dropped in a 1N4005 ... hopefully that won't be an issue (I'm pretty sure they're both 1A rated, but if she dies again, I'll pick up the right diode and maybe one with a higher rating and see if that works).

NOTE: If you decide to open your amp, you VOID THE WARRANTY ... so if you can get it fixed under warranty, go for it; if not, and you feel confident with a soldering iron - or have a friend who is - and it's a choice between your amp being a paperweight, or maybe getting fixed, then here's what I did...

After taking off the top cover (and for the Micro Terror also the inner cover), I removed the circuit board:
1) Micro Dark - Removed 3 1/4" jack nuts on the back (only 1 on the Micro Terror), and 2 on the front plus the 3 control knob nuts
2) Removed the bolts holding the circuit board to the chassis (only one on the Micro Dark, two on the Micro Terror)
3) Disconnected the cable for the LED Power Light
4) Tilted the board up carefully and slid it back and out
5) Examined the board for any bad components (this is when I found the bad Diode)
6) Removed and Replaced the bad Diode (NOTED THE POLARITY OF THE DIODE WHEN I REMOVED/REPLACED IT (One end of the diode has a white stripe, if it goes in backwards, it won't work).
7) Re-Assembled - IMPORTANT--- I Discovered the Power Switch should be in the ON position so that it slides into it's hole ... if it is OFF, it will jam in the bottom of the chassis and I was close to snapping it off

Plugged it in, hooked up a guitar and speaker and she runs like new.

Hope this is of some help to others!

[HNB]

Helpful post for people with that issue. Thanks for that!