Re: Independent board comparisons


"martin" <martin.reynolds@xxxxxxxxx> wrote in message news:1186083445.453545.60210@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
On Aug 2, 12:07 pm, MrSanRamon <mrsanra...@xxxxxxxxxxx> wrote:
On Jul 19, 8:20 pm, "GPE" <See_GPE_webs...@xxxxxxx> wrote:

> What we need is a pinhead with an electronics background who can not > only
> test and evaluate the operations of the boards BUT can also do a design
> evaluation as well.

What is going to make any "testing" credible is to not only see if it
operates in a game, but to do off-nominal testing.

This is going to be the challenge...off-nominal inputs and loads.

Not an easy task and near impossible for some items, like CPU's for
instance. These things may operate for a while, but what happens as
components age? A CPU has a lot of circuits that can cause things not
to work properly.

I don't want to stifle the project, only to point out to those that
are not especially knowledgeable that testing in itself is an art.

Robert

Well, you got that right. The 5V line can be 4.8V to 5.2V at the
regulator. The 50V line is 70V, and could be 80V. The 12V line could
be 11.4V, and that can push optos ovethe edge. Then, the whole thing
can be running at 40C, probably with low line voltage. Then, the test
parts may be better than spec so they all run, production parts may
meet spec exactly and then fail after 6 months in the field as the
southern states warm up.


Yeah, This is all the stuff you must take into account during the design of a board. You always design for worst case conditions - both temperature and voltages. That way when you're at nominal voltages and/or temperatures then you're always in the good.

However, I can see the point regarding in depth evaluation (what we call Acceptance Testing). I can test all I want as I know what I'm looking for. But testing at the extremes by an evaluator while installed in a machine - this is quite impossible. I guess about the only real evaluation that can be performed would be from a user point of view. Form/Fit/Function sort of stuff. How does it look, how does it fit, how does it work, documentatin, warranty, etc.

As far as user technical evaluations - the only thing that can be seen by anybody would be whatever people post on here... either good or bad. Crappy way to do get word out but I can't think of any other way. I do know that one RGP post of "why doesn't my board work?" speaks far, far louder than a post stating that a board is working fine...

-- Ed

FYI -- I ALWAYS like to get feedback on boards for improvements and always take the suggestions seriously. After more than 100 of the rectifier boards, I did get some feedback on that board for improvements - such as better solderability and "E" markings on bottom of board...these changes have been made and the next batch of boards are on order. A couple suggestions could not be incorporated, though ... such as LED's for voltages. I tried but just couldn't get them to fit on the board without disrupting current carrying traces. I also nixed putting Molex .093 type connectors between the transformer and board... why introduce more possible points of failure?


.

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