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Family Computer => Technical & Repair Assistance => Topic started by: umjammercammy on May 07, 2019, 08:33:00 am

Title: Micro Genius IQ-1000 Technical Issues
Post by: umjammercammy on May 07, 2019, 08:33:00 am
I have a Micro Genius IQ-1000 that's got a couple odd problems.

For starters, the power button doesn't work at all. The system turns on immediately the instant it's plugged in.

The second problem is that the audio is very crunchy and distorted. I just got done recapping the system but it had no effect on the audio at all. 
Would anyone have any idea what the problem is?
Title: Re: Micro Genius IQ-1000 Technical Issues
Post by: FAMICOM_87 on May 07, 2019, 11:36:26 am
is this famiclone NOAC ?
Title: Re: Micro Genius IQ-1000 Technical Issues
Post by: umjammercammy on May 07, 2019, 11:37:49 am
It's discrete, it had UMC chips inside originally. I swapped the UMC CPU for a legit Nintendo CPU but this has had no effect on the sound other than correcting the typical swapped cycles. The crunchy distortion is still there.
Title: Re: Micro Genius IQ-1000 Technical Issues
Post by: FAMICOM_87 on May 08, 2019, 12:55:06 am
did you try to get sound directly from pin 46 on the cartage slot  :question:
Title: Re: Micro Genius IQ-1000 Technical Issues
Post by: krzy on May 10, 2019, 12:46:23 pm
Quote
For starters, the power button doesn't work at all. The system turns on immediately the instant it's plugged in.

Button might be internally shorted (broken). You can try to fix it by disassembling everything and maybe bending a little the small metal element inside but those buttons (I call them isostats) need a litle patience when fixing, you can easily lose the spring for example or it can shoot into your eye:
https://www.google.com/search?q=isostat&source=lnms&tbm=isch&sa=X

Quote
The second problem is that the audio is very crunchy and distorted. I just got done recapping the system but it had no effect on the audio at all.
Would anyone have any idea what the problem is?

Probably some resistor in the audio-mixing circuint have incorect values. For example, the ones from CPU PIN1 and PIN2 into GND should be 100R, no more.
Title: Re: Micro Genius IQ-1000 Technical Issues
Post by: krzy on June 18, 2019, 03:10:47 pm
Few days ago I made a complete reverse-engineering of IQ-1000 and IQ-2000 - I recommend you reading schematic for those consoles here:
http://forums.nesdev.com/viewtopic.php?f=9&t=18984

The values of channel mixing resistor in audio path (R21, R20) should be 20k and 12k, not 390 and 240.
If console does not react on power-up then probably 4013 chip need to be replaced).
Title: Re: Micro Genius IQ-1000 Technical Issues
Post by: boye on June 21, 2019, 04:19:52 pm
Quote from: FAMICOM_87 on May 08, 2019, 12:55:06 am
did you try to get sound directly from pin 46 on the cartage slot  :question:

Pin 46 is an audio input, not an output.
Title: Re: Micro Genius IQ-1000 Technical Issues
Post by: P on June 22, 2019, 01:26:53 am
Nope pin 46 is final audio output. Pin 45 is input to the cartridge and amplified output from the APU.

Cartridge pinout (https://wiki.nesdev.com/w/index.php/Cartridge_connector)