Re: Commodore 65 and DIN8 cable

Date: Wed, 2 Mar 2016 15:50:19 +0100
Message-Id: <>
> On 2016-03-02, at 15:44, wrote:
>> On 2016-03-02, at 11:08, Michał Pleban <> wrote:
>>> Obviously I can't check this myself ;-) but if there are any EMI filtering elements on the signal's way out, those can be sometimes causing similar problems to what you describe.
>> A quick look at the motherboard show that it's probable - there are
>> several capacitors labeled EMI91x soldered around the connector.
>> Do you have any suggestion on what to do with them?
> Well, I can imagine that with this kind of board you don't want to remove/replace those unless proven necessary to do so. What I would probably do first in such situation is that I'd check if I could make the lines "open" f. e. by removing socketed ICs or so and measure all of the lines, checking for noticeable differences in capacity/resistance among them.

If you have valid schematics at hand, please check if those are only capacitors there. There might be other elements like Rs, FBs, ... Checking all of them under highly magnifying glass could sometimes reveal the cause too. I had a situation when an FB was seemingly intact but was in fact mechanically broken. When measuring, the pressure caused the problem to disappear but it became apparent when perusing under magnification and differently applied pressure.

Of course it may not be the case with your board. Just an idea about what can give similar symptoms.


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Received on 2016-03-02 15:01:11

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