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Old 14th February 2007, 10:46 AM   #1
delory is offline delory  United Kingdom
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Default DC Offset Problem with Micromega Amp

Hi,

I have just replaced a Micromega Tempo 2 amp (working perfectly) with a Tempo P pre-amp and a couple of Audiolab 8000M monoblocs. When I connected everything up, unfortunately I didn't notice that one of the Audiolabs was switched on, not that I'm sure this was a problem. Anyway, when all was connected I turned on the Micromega and received a loud burst of music through the speakers (approx 1 second) then the pre-amp switched off and started flashing "dco" - meaning DC Offset.

Now if I disconnect the pre-amp from everything else, and just plug the power supply into it, it still shows the same error message.

Reading the Micromega manual, both the Tempo 2 and the Tempo P have this safety setting, but the Tempo 2 still works fine. However it says if the Tempo 2 says "dco" then return it to Micromega, but if the Tempo P shows it, then it is the power amps which are faulty.

Can anyone enlighten me as to what the actual problem is? Is it the pre-amp, or the power amps? If it is the power amps, why is the message still appearing on the pre-amp when it is not connected to anything? Does this mean that something has broken:blown in the pre-amp or will it "reset"? Reading another post on DC Offset, one user said that he measured the DC from his amp, and it peaked when the amp switched on, then after about an hour it disappeared.

Any help appreciated, as sending things off to Micromega is not cheap!!
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Old 14th February 2007, 11:06 AM   #2
Netlist is offline Netlist  Belgium
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Without knowing the preamp, the output buffer might be faulty. Check fuses, try to locate and measure the output transistors.
Picture of the inside?

/Hugo
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Old 14th February 2007, 11:08 AM   #3
delory is offline delory  United Kingdom
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Ok, I'll take a pic and post it here if it will help.
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Old 24th December 2007, 07:12 PM   #4
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I recently repaired my tempo 2.
This amplifier seems to be very sensitive to DC output because it is DC-coupled.
I have written some words about it in french - apologizes ! when it got a second youth... definitely a nice amp.
Here is my webpage (I am not allowed to publish it) :
http://lappweb.in2p3.fr/~fournier
then look for micromega tempo 2.
btw, if you are interested by the phono preamp, I am still experiencing because I could not easily make a PCB. I expect to to it asap...
Cheers
Laurent
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Old 1st May 2011, 10:33 PM   #5
mbosko is offline mbosko  Yugoslavia
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Hello

I have Micromega Tempo 2 amplifier but digital part is defective

Who can help me with EPROM HEX dump

Eprom is 27C256 Label TEMPO/V1.5

thanks a lot
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Old 2nd May 2011, 07:57 AM   #6
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Default to mbosko

Hi,
I don't have my archives here, I have a look asap for the PROM (I think it is a v1.5). BTW, check the short ribbon between the power section and the preamp, the connectors may have been oxyded. I had to replace it since it was almost out of order and I had some grounding issues. Be careful, these connectors are fragile. Also check the auxiliary power supply coming from the transformer and the small connectors around. You should then ensure that the microcontroller (the 40-pin IC on the preamp) has its 5V (between pins 20-GND and 40-+5V).
In the meantime, I check for the EPROM...
Cheers,
Laurent
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Old 2nd May 2011, 01:37 PM   #7
mbosko is offline mbosko  Yugoslavia
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@ Laurent

Hi

Thank you very much for support
I am waiting for EPROM file
You can email to mbosko@ptt.rs


Thanks a LOT
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Old 6th May 2011, 08:53 AM   #8
mbosko is offline mbosko  Yugoslavia
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Just received letter from "new" Micromega

"Dear Sir,
Thank you for your message and your interest for HD MICROMEGA products.
Actually,the ex-Micromega company has collapsed about three years ago, and isno more existing... "
So, will be a lot of problems for owners of Micromega products
It is not possible to get users manuals for older products , imagine servicing ?
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Old 14th May 2011, 05:43 PM   #9
ikap is offline ikap  Serbia
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HI,
I have Micromega Tempo 1 Firmware, possiblly, it`s same!
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