On Sat, 20 Oct 2007 20:36:10 -0700, the renowned John Larkin
wrote:

On Sat, 20 Oct 2007 18:36:04 -0700, ChairmanOfTheBored
wrote:

On Sat, 20 Oct 2007 14:04:48 -0700, John Larkin
wrote:


I noticed a few process indicators to mention to your PCB maker's QA
folks. Not the contract makers the assembled the unit (or you guys if it
was your folks), the PCB itself.

The stains under the dip package location are indicative of mask
delamination or poor adhesion of it. A condition known as "haloing".

I think that's just the lighting. The board looks OK to me.



Change the resistor packs to the next form factor size up perhaps.

Yeah, we should stop using these things.

There are two edge forms, one is a bit more expensive and solders a
bit better IME. My most recent tiny board (1.75 x 2.9") has 10 of them
(0603x4) which is a lot nicer than 38 discrete 0603 or 0402 resistors.


They must be on the bottom of the assembly as I don't see them
anywhere.

R34 on top, near the two big blue inductors, is one. There are several
more on the bottom, near the uP. These things just don't solder well.
The other part we have trouble with is the US8 packages, the ones on
the bottom with red epoxy holding them on. Hard to solder, hard to
inslect, a real SOB to replace.


Nice layout, John.

Thanks.

John


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
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