Zebra Strip Contact Reliability

Jim Yanik <jyanik@abuse.gov> wrote in message
news:Xns9B375E56879CBjyanikkuanet@74.209.136.84...
"N Cook" <diverse8@gazeta.pl> wrote in
news:gd1j07$9ea$1@inews.gazeta.pl:

N Cook <diverse8@gazeta.pl> wrote in message
news:gd1iqu$8q9$1@inews.gazeta.pl...
hr(bob) hofmann@att.net <hrhofmann@att.net> wrote in message
news:cd9b176d-b9f3-4a32-847a-48459ee34e3e@d70g2000hsc.googlegroups.com
... On Oct 13, 7:43 pm, "William Sommerwerck"
grizzledgee...@comcast.net> wrote:
No solution other than to repeat cleaning that I know. Some
configurations are more susceptible. I just recently cleaned
a Fluke 77 display that worked for 20 years that developed
a segment that had less contrast than the others.

I cleaned my Fluke for the second time, scrubbing the PCB contacts
thoroughly with alcohol. I was about to ask the group if anyone
knew of
a
safe way to clean the zebra contacts. (The very first cleaning
needed in nearly 20 years occurred four or five months ago.)

Any chance of coating the stripes with the conductive paint used for
automobile window heater strips. That would provide a new conductive
surface, and would be a bit thicker so that there would/should be
more pressure on the contact point.

Bob Hofmann


precisely wrong advice, we are talking about zebra strip here, the
point
of
it is exact alignment, between pcb pads and LCD lands, is not
required

I wonder who dreamt up the concept ?

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/






afterthought , I suppose you meant conductive paint added to the pcb
pads (stripes), not the zebra (stripes)




why not use gold leaf on the PCB pads,build up thickness(increasing
contact pressure)?
conductive paint will be soft and contact pressure will force it aside and
possibly short out adjoining pads.

--
Jim Yanik
jyanik
at
kua.net
Click to expand...
I know a specialist plasterer who uses gold leaf (employed after the fire at
Windsor Castle). They use size to get the gold to adhere. Maybe it would
adhere to copper/polyester without size but its very dificult to use.
Assuming you would rub a strip over the pads and then cut into the gold
between the pads. I'll have to ask him whether gold leaf would snag/tear
rather than cut.
I'm thinking gold leaf may be useful, if it melds, for fine track repir on
pcbs instead of conductive paint , which does cut cleanly along the
inter-trace lines.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
one guess is that the zebra strip is just fine but the pc contacts are
corroding. Shine the pads up with some #0000 steel wool, protect
them from corrosion with a dab of silicone grease, and reassemble.
Worth a shot.
 
"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
news:nfKdnWPlkOl0TGnVnZ2dnUVZ_t_inZ2d@earthlink.com...
Old Tech wrote:

I have this problem on a car radio LCD display, when I get round to
it
I am going to try something that we used to do on old TV turret
tuners - the contacts were silver plated and needed cleaning fairly
regularly. However, if after cleaning a VERY thin smear of vaseline
was applied to the contacts it was rare to have to clean them
again.
You may think that the vaseline would insulate rather than improve
contact, but the light pressure of the leaf contact was enough to
push
the vaseline aside. Vaseline is self healing so prevents oxidation.
I
have used it successfully in remote control handset contacts, pots
in
guitars and amps and even the home telephone. I would stress that
the
smear of vaseline we are talking about here is just that - a very
light smear so as to almost be invisible. Wether or not it will
work
on non-moving contacts remains to be seen.

Roy the Old Tech


Great idea. Then you can buy a new radio.

Why? If it doesnt work I will simply clean off the vaseline.
Click to expand...

Roy the Old Tech
 
Old Tech wrote:
"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
news:nfKdnWPlkOl0TGnVnZ2dnUVZ_t_inZ2d@earthlink.com...

Old Tech wrote:

I have this problem on a car radio LCD display, when I get round to
it
I am going to try something that we used to do on old TV turret
tuners - the contacts were silver plated and needed cleaning fairly
regularly. However, if after cleaning a VERY thin smear of vaseline
was applied to the contacts it was rare to have to clean them
again.
You may think that the vaseline would insulate rather than improve
contact, but the light pressure of the leaf contact was enough to
push
the vaseline aside. Vaseline is self healing so prevents oxidation.
I
have used it successfully in remote control handset contacts, pots
in
guitars and amps and even the home telephone. I would stress that
the
smear of vaseline we are talking about here is just that - a very
light smear so as to almost be invisible. Wether or not it will
work
on non-moving contacts remains to be seen.

Roy the Old Tech


Great idea. Then you can buy a new radio.

Why? If it doesnt work I will simply clean off the vaseline.

Roy the Old Tech
Click to expand...

Good luck, if there is anything of the Zebra strip left to clean.


--
http://improve-usenet.org/index.html

aioe.org, Goggle Groups, and Web TV users must request to be white
listed, or I will not see your messages.

If you have broadband, your ISP may have a NNTP news server included in
your account: http://www.usenettools.net/ISP.htm


There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top