ADA Depot - A Forum To Support Users of ADA Amplification Gear
Let's Get Technical => Troubleshooting Problems => Topic started by: hal2000 on January 23, 2014, 08:36:09 AM
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Hi ADA Fans,
my MP1 doesn't start up anymore. There is a dot and the number 8 blinking in the display. And 2 groups of the other leds are blinking. Sometimes it gets to start right, but when i try to edit something it goes in this blink mode after some time. Could it be a power problem? I've just replaced the battery. I attached a video showing the problem in action.
Thanks for a little help...
Greets Harald
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This can happen to mp-1's and can have different causes.Take the 2 tubes out and start it up again,let me know if that does help or not.
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Thanks for your answer. Yes, when i remove the tubes, all is going right. Now i have put in 2 new ones but that didn't make any difference.
What now? Running without tubes wouldn't solve my problem ;-)
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Well now you can use the SS chanel ::) :facepalm:
The problem comes from the power supply.So first i need to know the wall voltage,if it's to low this can happen.It can be other things but this is the easiest to check.Can you measure the wall voltage?
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Thank you so much MarshallJMP (i own the jmp 1 as well ;-)
I have 2 problems: My English is not as good to discuss technical things. Second is my poor knowledge of electronics.
Anyway, i have a mulitmeter. So if you can tell me what a wall voltage is or where i have to put my cables of my multimeter,
i can measure.
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The wall voltage is where you you put in the mains connector.110 or 220V depending where you are from?
And a warning,be carrefull you don't electrocute yourself!!!!!!!!!!
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The "wall voltage" is measured were you plug in the MP1 power cable. So set you multimeter to AC volts the range (if it's adjustable) to handle 110v or 220v (what voltage does your country use?), being careful, (you want to measure between the active and neutral, not the earth of ONE of the power outlets). Turn the power point on and measure the AC voltage between the active and neutral. Power points/outlets are typically either 2 pronged or 3 depending on country etc. 2 pronged (1 is active, the other neutral), 3 pronged 1 is active, 1 neutral, and one earth (earth pin is sometimes a different shape/size) Check this article (http://en.wikipedia.org/wiki/AC_power_plugs_and_sockets) on the different types around the world.
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Hi guys,
that is a really nice forum with nice and competent users. Thank you again.
So, i'mfrom germany and the wall voltage (i understand: voltage that comes out of the wall ;-) is exactly 220 V, as it should.
I think the more interesting part would be the voltage of the transformer outputs, right? Does anyone knows the values?
Thanks in advance...
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Hey hal2000, always happy to help :wave: , as I'm sure you can tell we LOVE out ADA gear.
MJMP will no doubt help you with that. If it ends up being a transformer issue this is the best solution (http://www.marshalljmpmodshop.net/miscellaneous_parts_and_replacement_tubes.htm). The MDRT (Mchinator Developed/designed Replacement Transformer) is the one to go for. Unfortunately Machinator didn't do one for the MP2 just the MP1 and MB1 (so you are in luck). MJMP is in Belgium so you could take/send your MP1 to him to get fixed (he is the technical guru (and all round nice guy :thumb-up: )). There are some MP1 noise reduction mods worth doing as well.
Regards Richard
Open the pod bay door please hal, I'm sorry Dave, I can't do that......(I'm assuming that's your handle reference ??)
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@rnolan:
Please, i'm german. Only very simple sentences. The last italic one i didn't understand.
The best solution for me is to repair it by myself, to learn a bit about electronis. I'm able to solder
things and i know rudimentary stuff about electronic parts and their functions. Thats it.
Remove and install a transformer would not be that problem. Even if MJMP earns money for
his life with repairing things, i would try it by myself.
I love the Guitars, Amps and Effectunits from the 80's. So i find it important to keep them up
and play them as long as they are running. All that digital modelling stuff doesn't satisfy me.
So i have some wonderful old things: ART SGX 2000, Marshall JPM 1, Rocktron Repiflex and
the ADA MP 1, which i wish to reanimate again.
"Save the old ones..."
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Hey hal2000, the italic reference is from the movie/book 2001 A Space Odyssey (Arthur C Clarke) which is were the HAL2000 computer ran/controlled the space ship (Dave was trying to get back inside the space ship and HAL wouldn't open the door (pod bay) for him to come in, Dave was piloting/flying (in space) one of the ships small pods). I was just wondering if that's were you got the name (handle) hal2000.
The MDRT transformer replacement (my understanding) is not to difficult/hard to do. And it comes with good instructions. It is also an upgrade making your MP1 better (but does cost more than an original replacement).
I agree with you about the tone cloning/digital modelling, I like the older gear (particularly tube) and these days (it seems) I'm very "old school".
Ok, so you have good stable 220v from the wall outlet (power point), MJMP was trying to rule that out as the cause/problem because it was easy to check/test.
Next he will probably get you to check the various voltages of the transformer outputs. Once you/we work out the problem, we can then work out the solution ;)
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Ok wall voltage looks good but a bit on the low side.Normally in europe the standard voltage is 230V.
Next thing to do is measure the voltages comming from the transformer.I attached a pdf file,so take a look at it.Do some measurments and let me know.BTW all these voltages are AC,so make sure you set the multimeter to AC.
Also measure the voltage over the 3300µF/16V cap (it's the big one near the transformer).This is a DC voltage.
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Hi MJMP,
thank you. But you don't need to send me those PDF's. I have already downloaded all shematics from your site.
Now i have 2 understanding problems. My transformer has 6 outputs. All shamatics have 7 outputs. And the
second thing is: When i put one cable of the multimeter to one transformer output, where do i have to put the other cable
of multimeter? Neutral of the wall socket? Same question for the cap. Red multi-cabel to + and black one to - of the capacitor?
Sorry, but i'm not that electronic freak...
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Transformer
Red-Yellow
Red-yellow (the second red one)
Green - Blue
Green - Blue (the second green one)
The other one (grey - orange goes to the tubeboard BTW.No need to measure this.
This is AC voltage
For the cap,red = + ,black = -
This is DC voltage
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Red-Yellow = 17,4 V
Red-yellow (the second red one) = 16,7 V
Green - Blue = 8,6 V
Green - Blue (the second green one) = 10,7 V
For the cap,red = + ,black = - "I don't know wich Cap". There are 2 caps soldered together.
Together thy have 3000µF + 220µF = 3220µF ) Is it that? This is 9 V DC.
Please look at the attached photo.
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First voltage looks normal but the second isn't.The green blue differ too much from each other.Could be diode D38 or D39 is busted.Also with this type of transformer the 9V is also a bit low,should be more like 10 to 11V.
Now something to try out is bridging that big white resistor.Just solder a wire over this resistor.This could also solve your problem.But i would take a look at D38 and D39 also.These are 1N4007 diodes,really cheap and quite easy to replace.
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Hey MJMP,
guess what! I've bridged the white resitor and ADA is coming up! So, first of all: Thank you very much. You make me believe to get that beast repaired.
OK, is'nt that bridging of the white resistor dangerous? Could that damage any other parts? Can i leave the bridge or do i have to choose another resistor?
What obout the diodes? Must i do this job too, even when this resistor-thing does the job?
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No,it's no problem bridging this resistor,later mp-1's didn't have this resistor anymore.
Do you have a diode tester on your multimeter?
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Yes, my multimeter has a diode tester. But i don't know how to use it. The manual doesn't tell anything about it.
Do i have to solder the diodes out or can i measure them leaving them on board? If yes, do i have to switch the
ADA on? (I think the multimeter makes his own voltage, right?).
So, if i have to solder them out, i can replace them without measuring. Do i have to prefer a type, or is it the standard
IN4004 ?
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Read this on how to test them http://www.allaboutcircuits.com/vol_3/chpt_3/2.html
No you can leave them in but you need to pull the connector comming from the transformer.Also don't start it up when testing.And to be safe unplug it.
You need to use 1N4007 diodes should you want to replace them.
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The diodes are all OK. So i will remove the resistor and bridge it and all is OK?
Thank you for so much assistance and patience.
@rnolan: Thank you too.
Greets from Cologne
Harald
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yes,just find the voltages you measured strange.