Re: Silicon oil leakage on PCB - how to remove?

On 27 Apr 2005 07:19:34 -0700, "Tim Shoppa" <shoppa@xxxxxxxxxxxxxxxxx>
wrote:

>> If e.g. a drop of the stuff lands on the balanced mike
>> amplifier - the whole goes out of bias and the
>> mike input is effectively dead.
>
>OK, before you said video and codecs, which is rather low impedance
>stuff, but a mike amp will be very sensitive to megohm level
>impedances.
>
>> Also some Audio / Video DA's were observed to stop.
>
>As Spehro asked, any CMOS crystal oscillators?
>
>Tim.

The design (A Tandberg H323 Codec board) contains several dedicated
clock oscillators (complete Xtal+osc assemblies in a metal can) on
various frequencies. All work. (no oscillators on a "leftover" CMOS
gate)

Video parts also contain DA's / amps, that at some level run
impedances substantially higher than 75 Ohms.

The design has several separate operational parts that communicate
with each other - if one partial function does not chime in, the rest
may also not initialise. This makes cause / effect hunting a little
tricky. The balanced amp example is a nice "stand alone' function I
observed to fail when exposed to the oil.

Am I sure it's Silicone oil? Well - that is what the damper data***
tells me, but whatever special dopes are present I do not know.

Suppose "megaOhm" circuits were involved - would this be normal
behaviour for silicone oil?

I am now toying with Fluxclene - see what good that does...

Thanks for all suggestions mentioned so far by many. I will try the
Decon lead.

--
- René
.

Quantcast