Re: plus4 power supply

From: Nicolas Welte <>
Date: Sat, 22 Sep 2012 18:22:17 +0200
Message-ID: <>
Gerrit Heitsch wrote:
> On 09/22/2012 05:55 PM, wrote:
>> But there are two pins allocated for +5. Just by adding second pin to 
>> the plug they could have doubled the current there.
> You also need 2 pins for GND to make that work properly. Otherwise you 
> still have a bottleneck.

The C64 Powersupply that I upgraded with the Astrodyne SMPS uses the full 7 
  pins. 3 GND and 2 for +5V.

It's also interesting, that at least the first C64 PCB came with only one 
of the +5V pins wired internally. There is a note in the service manual 
that a wire is to be installed to connect the second pin. Why this was done 
is a mystery to me, since all C64 power supplies that I know, use only a 
single +5V pin. Even the power supplies that have all 7 pins physically 
installed, have only a single +5V pin connected.

I've never seen an original power supply that came with the 1764 REU. Maybe 
those had both +5V pins connected?


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Received on 2012-09-22 17:00:38

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