Re: [tlug] rf noise

[Jim Tittsler <jwt-tlug@example.com>]

On Tue, Feb 10, 2004 at 11:16:24AM -0800, Jonathan Byrne wrote:
> another of the many sources.  The main one is still the CPU, and since this 
> didn't happen until after your upgrade, the CPU/mobo are your main culprits.  

Which includes the way the motherboard connects to the outside
world. There is a large variation in the quality of decoupling
of the external ports from one motherboard to another (even
within the same company).

Having helped get several computers through RFI testing, I'm of
the opinion that it is best to be methodical and try to
localize the source rather than using a shotgun approach.
At least for repeatability.  :-)

> CPUs do put out lots of RF interference.  Back in the old days, there was a 
> program (probably several, for various platforms) that could play music over 
> your radio if you put it close to your TRS-80.  It caused the RF output of 

Hah.  We used to do that with a PDP-6.  But in that case, it
wasn't the CPU you were hearing, it was the current switching
the front panel lights off and on.

Jim

-- 
Jim Tittsler                                         GPG: 0x01159DB6
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