Amiga 2000: No Sound

[TheWizard]

Is it possible that the RCA contacts on the motherboard are cracked?

The Wizard

[Ral-Clan]

This might seem obvious, but have you ruled out your speakers as the cause of the failure?

Have you tried the Amiga with all new cables & speakers?

Is there a Digital to analogue convertor between the Paula and the RCA outputs?  I'm just thinking, if it's not the Paula, and not the jacks, cables or monitor, and not a software problem, then it must be something in between the Paula and the RCA jacks.  Maybe a line-level pre-amp or D/A circuitry.  Maybe just a dead capacitor or resistor or something.  Anyway, it sounds like this Amiga can be fixed if you're willing to put out a little cash or effort.

[Fester]

Hi There,

Thanks for all the input. I don't know what this means exactly, but there seems to be a power problem on the serial port. The A2000 manual shows PIN 10 as -12V. My meter reads -11 volts, which is close enough. But when I try Pin 9, which is described as +12, I get a 1.6 volt readout on my digital meter.

As far as the Paula being dead, I am not sure yet. I'll try replacing it when the new chip arrives.

If it turns out that replacing the Paula and the PSU doesn't help, I might just send the motherboard somewhere.

Fester

[Fester]

ral-clan wrote:
This might seem obvious, but have you ruled out your speakers as the cause of the failure?

Hi, yes I have. I tried a different set and tested both the monitor and the other speakers with a different input device. They work fine. The cables and speakers and monitor all work.

Oh well...I can try switching Paula and PSU. After that, I'll just send it somewhere...

Fester

[Ral-Clan]

Ok, but test your Amiga with a different power supply before you try the new Paula chip.  You don't want the new Paula chip to be damaged if there is a problem with your original power supply.

Sorry to hear of your problems.  We've all had them.  But I do think that getting Amigas fixed (repaired) rather than trashing them is a good idea, even if it is slightly costly.  The supply of A2000 motherboards is finite.  Every time a user trashes one rather than going the extra mile to get it repaired means one less A2000 out there!  They may still seem plentiful on Ebay at the moment, but they aren't getting any cheaper there either (which is amazing for a 15 year old computer, ain't it?).

[Fester]

ral-clan wrote:
Ok, but test your Amiga with a different power supply before you try the new Paula chip.  You don't want the new Paula chip to be damaged if there is a problem with your original power supply.

Absolutely. Good point.

ral-clan wrote:
Sorry to hear of your problems.  We've all had them.  But I do think that getting Amigas fixed (repaired) rather than trashing them is a good idea, even if it is slightly costly.  The supply of A2000 motherboards is finite.  Every time a user trashes one rather than going the extra mile to get it repaired means one less A2000 out there!  They may still seem plentiful on Ebay at the moment, but they aren't getting any cheaper there either (which is amazing for a 15 year old computer, ain't it?).

Very very true. I could just buy another A2000 mb on eBay, but I want to fix this one. Just cuz...

Fester

[amiga_3k]

The low voltage on pin 9 is indeed a little thing that could make you worry. Have you checked all other functions of the Amiga? I'm thinking of fully functioning mouse / joysticks, floppydrives, printer? If it's Paula, chances are that mouse / joysticks are mis-behaving. CIAs can (and in many cases do) cause sound/serial related errors as well. So, make sure the PSU is okay and also check for short-circuits. And... check ground! Currents tend to flow in the direction of the least resistance. If the normal ground connection is corroded causing a bigger resistance then, say, the audio-ground then the currents will take that route, making a total mess of your system.

[Fester]

Greetings,

I found the problem. It's my monitor and my own stupidity. I didn't test it properly. I don't know how I missed this but I did.

The A2000 sound is fine. It works as it should. My 1084's sound however, that's another story. I will add external speakers.

Nevertheless, it wasn't a total waste of time to open the Amiga box and look inside. I upgraded it to 3.1 ROMS and seated my two internal floppies properly so they appear straight in the casing window. I also whiped out the hard drive and loaded OS 3.1 and a bunch of software.

Fester

[TjLaZer]

Great glad the old 2000 is fine.  Did you check the battery and remove it?    I recently got a nice 2000 and the battery was leaking so I removed it just in time.  No battery in it now but there is no need for one really.

[Fester]

TjLaZer wrote:
Great glad the old 2000 is fine.  Did you check the battery and remove it?    I recently got a nice 2000 and the battery was leaking so I removed it just in time.  No battery in it now but there is no need for one really.

Hi TjLaZer,

As a matter of fact, there was no battery in there when I purchased it off eBay. I ordered a new battery from AmigaKit last week just for fun. My Amiga displays dates in the 1970s. I assume that has to do with the absence of the battery.

Fester