ADA Depot - A Forum To Support Users of ADA Amplification Gear

Let's Get Technical => Power Amp Tech => Topic started by: omivai on December 23, 2013, 07:20:03 PM

Title: ADA Microtube - "protect" problem
Post by: omivai on December 23, 2013, 07:20:03 PM
Hi everyone, i have an ADA Microtube that goes into protection mode for several minutes, then powers up , and sometimes not.

Does anyone here have an idea on what could be the issue?

THANKS!
Title: Re: ADA Microtube - "protect" problem
Post by: Dante on December 23, 2013, 09:39:39 PM
Hi Omivai, Welcome to the Depot!

I don't know which Microtube you're using, but my MT200 does take a bit to fire up sometimes. Other times, it's like 5 seconds and BAM, it's on. There were many discussions on the old forum about how to rectify the issue, I'm sure a tech-oriented member will chime in with suggestions.

Be patient, the forum is still pretty new - it's still all shiny and smells kinda funny. Gotta break it in a bit
Title: Re: ADA Microtube - "protect" problem
Post by: omivai on December 24, 2013, 07:24:20 AM
Thanks Dante, mine is a MT200 to.
Title: Re: ADA Microtube - "protect" problem
Post by: Kim on December 24, 2013, 09:57:01 AM
My MT200 takes a little more than one whole minute before coming out of Protect.  I can get it a bit sooner by shining a flashlight into the front vents. 

In "light" of this, see if it comes on sooner when the unit is out of the rack and the top lid is off.   
Title: Re: ADA Microtube - "protect" problem
Post by: El Chiguete on December 24, 2013, 07:30:14 PM
What is ¨protect¨, mode?
Title: Re: ADA Microtube - "protect" problem
Post by: Dante on December 25, 2013, 09:56:01 AM
Protect Mode = When you first turn the amp on, it's in Protect Mode. A light is on while in Protect Mode, and no sound comes out until the amp is 'ready' at which time the light is extinguished and the amp fires up.

It can be a by trying to sit there and wait...and wait...and wait.....for that damn thing to fire up. Just be patient and it eventually will.
Title: Re: ADA Microtube - "protect" problem
Post by: El Chiguete on December 25, 2013, 07:23:38 PM
Ohh well then the MicroTube 100 doesnt have that light. It has independent Power and StandBy switches.
Title: Re: ADA Microtube - "protect" problem
Post by: Sparker on December 26, 2013, 01:14:57 AM
Hi Guys, and hope you all had (or still having)  :homer: a Merry Christmas.

I think when the MT200 PSU startup thing was discussed some time ago, the neon inside the box, NE1 (a NE-2H type) was thought of as a suspect. This neon acts as an under-voltage protection for the PSU chip when the amp is switched on, when the neon strikes on the PSU chip is brought out of shutdown. The neons can degrade over time and the strike voltage can change, also they can show sensitivity to light - so shinning a torch in the case may not seem so strange. Not sure where the neon is inside the box, but you could confirm the problem by looking at the shutdown pin of the PSU chip when you switch the amp on. Covers off, multi-meter needed, high voltages present so leave it to a tech if you don't fancy getting your hands dirty. Or, just swap it for a new one and see what happens.

Hope this helps

Mike
Title: Re: ADA Microtube - "protect" problem
Post by: MarshallJMP on December 26, 2013, 01:57:01 PM
Only the MT200 has the protect  led.This is because it's the only ADA amp that has a switching power supply.Like sparker said,change the neon bulb and the problem will usually be solved.Let me know if you can't find one,i have a few lying around.
Title: Re: ADA Microtube - "protect" problem
Post by: Dante on December 26, 2013, 06:07:24 PM
I had no idea that bulb was in there, and I thought Kim was making up stuff (as he is known to do) when he said it would come on with a flashlight! Go figure...
Title: Re: ADA Microtube - "protect" problem
Post by: omivai on December 27, 2013, 11:32:25 PM
Thanks to everyone and specially to Sparker!!!! it was the Neon bulb!! I replaced it and it started up inmediatly, and all for one argentine pesos!
Thanks a lot, and sorry for my english.

 :thumb-up:
Title: Re: ADA Microtube - "protect" problem
Post by: Sparker on December 28, 2013, 09:20:56 AM
Hey, no problem, good you got it sorted. Don't forget it's all team effort here!! If it wasn't for Kim and the problem with his little flashlight, I would never have remembered.  >:D
Title: Re: ADA Microtube - "protect" problem
Post by: frehley6986 on May 13, 2014, 06:00:02 PM
Thanks to everyone and specially to Sparker!!!! it was the Neon bulb!! I replaced it and it started up inmediatly, and all for one argentine pesos!
Thanks a lot, and sorry for my english.

 :thumb-up:

Hi
Can you tell me where to get a neon bulb for the 200? I have about a 9 minute protect mode on power up.
I thought it was a capacitor or two. Never heard of the neon bulb.
Thanks in advance
Title: Re: ADA Microtube - "protect" problem
Post by: rnolan on May 14, 2014, 08:07:41 AM
If you search posts for neon bulb  (or just neon) there's a post which has what you need IIRC
Title: Re: ADA Microtube - "protect" problem
Post by: MarshallJMP on May 14, 2014, 10:30:30 AM
Thanks to everyone and specially to Sparker!!!! it was the Neon bulb!! I replaced it and it started up inmediatly, and all for one argentine pesos!
Thanks a lot, and sorry for my english.

 :thumb-up:

Hi
Can you tell me where to get a neon bulb for the 200? I have about a 9 minute protect mode on power up.
I thought it was a capacitor or two. Never heard of the neon bulb.
Thanks in advance

Were are you from?
Title: Re: ADA Microtube - "protect" problem
Post by: frehley6986 on November 26, 2017, 08:50:21 PM
Where are you from?

Sorry I kinda lost track of this post as I hadn't messed with my rack. I'm in NY. I just ordered the neon bulb and hope to replace it this weekend. Thanks all

Title: Re: ADA Microtube - "protect" problem
Post by: rnolan on November 28, 2017, 01:23:32 AM
Hope it sorts your problem  :thumb-up:
Title: Re: ADA Microtube - "protect" problem
Post by: frehley6986 on November 30, 2017, 02:22:11 PM
My neon bulb(s) arrived today. I installed it and turned it on and NO PROTECT MODE....whooo hoooo

Thank you to everyone for all your posts. A lot of it is way over my head but some of it soaks in. This amp was purchased from a friend who later died in a car accident. I know it wasn't sentimental to him but it was something of his so I want to keep it going.

Hope it sorts your problem  :thumb-up:
Title: Re: ADA Microtube - "protect" problem
Post by: rnolan on November 30, 2017, 10:04:48 PM
Great news  :thumb-up: :whoohoo!: