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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Painkiller on February 20, 2008, 03:26:29 PM

Title: Confused with A1200 audio connectors.
Post by: Painkiller on February 20, 2008, 03:26:29 PM
Ok here is the deal have A1200 where the RCA connectors have been removed. So I was thinkin that I install traditional RCA connectors for it, but then stumbled upon something really odd. When the board has the original RCA connectors The left tand right audio poles are connected together :-? How is this possible I mean isn't the A1200 audio stereo which would be damn well impossible to achieve when the left and right poles are connected together or am I missing something here? I'm currently looking at the schematic and needless to say I'm really confused...
Title: Re: Confused with A1200 audio connectors.
Post by: motorollin on February 20, 2008, 03:28:43 PM
A1200 is indeed stereo. Are you absolutely certain you're not looking at the grounds?

--
moto
Title: Re: Confused with A1200 audio connectors.
Post by: Phantom on February 20, 2008, 04:49:08 PM
Motorollin is right. I think all Amigas are stereo.
Title: Re: Confused with A1200 audio connectors.
Post by: Painkiller on February 20, 2008, 05:31:25 PM
Quote

motorollin wrote:
A1200 is indeed stereo. Are you absolutely certain you're not looking at the grounds?

--
moto


I'm 100% certain. Measure it yourself if you don't believe me from pole to pole the left and right channel are connected   :-o
Title: Re: Confused with A1200 audio connectors.
Post by: Castellen on February 20, 2008, 06:29:30 PM
The RCA jacks contain switches which join the independant left and right audio channels together if a single (mono) RCA cable is plugged into the computer.  Likewise, you'll also measure a short with nothing plugged in.

I've written more detail about it here (http://amiga.serveftp.net/audio_repair.html), the schematic (http://amiga.serveftp.net/images/AudioSchematic-large.jpg) also shows this detail (poorly).
Title: Re: Confused with A1200 audio connectors.
Post by: taunusand on February 20, 2008, 06:44:08 PM
Quote

Castellen wrote:
The RCA jacks contain switches which join the independant left and right audio channels together if a single (mono) RCA cable is plugged into the computer.  Likewise, you'll also measure a short with nothing plugged in.


I agree. Never noticed this before, but when reading this thread, I just had to check it on my own A1200  :-D
Title: Re: Confused with A1200 audio connectors.
Post by: Painkiller on February 20, 2008, 06:58:55 PM
Quote

Castellen wrote:
The RCA jacks contain switches which join the independant left and right audio channels together if a single (mono) RCA cable is plugged into the computer.  Likewise, you'll also measure a short with nothing plugged in.

I've written more detail about it here (http://amiga.serveftp.net/audio_repair.html), the schematic (http://amiga.serveftp.net/images/AudioSchematic-large.jpg) also shows this detail (poorly).


Thank you for the info. I couldn't quite figure it out from the schematics I was looking at. BTW is there any place where I could buy these original connectors that have the switches?
Title: Re: Confused with A1200 audio connectors.
Post by: Castellen on February 21, 2008, 05:28:00 AM
Good question, I've never seen these particular connectors stocked by any of the electronics wholesalers I deal with.

I doubt Commodore would have had them made especially, so you could try the likes of Digi-Key to see if you can find modern equivalents.
Else I have some 2nd hand ones which I could supply if you needed a small quantity.  Email me if interested.
Title: Re: Confused with A1200 audio connectors.
Post by: rkauer on February 21, 2008, 07:11:27 AM
 Just checked.

 I confirm the RCA jacks on 600 and 1200 have a switch.

 If only one plug is connected, the stereo audio out is mixed.

 But, if you want to source this connector, take it from a dead motherboard (and I said really DEAD).

 I suppose any Amiga, since A1000 have this very same connector.

 In a second tough: why bother? Simply put conventional RCA jacks in it. I doubt anyone want to use mono in their Amiga, anyway. This feature is only useful with A520 or a mono TV set.