Searching \ for '[EE]: Fluke meter LCD problem' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/lcds.htm?key=lcd
Search entire site for: 'Fluke meter LCD problem'.

Exact match. Not showing close matches.
PICList Thread
'[EE]: Fluke meter LCD problem'
2002\08\10@145938 by Pic Dude

flavicon
face
Got a Fluke 8060A DMM here, that has had an LCD problem since it was
new.  The LCD display is dim, and over time has dimmed more to the point
where it's almost gone.  I used to be able to see enough to use it, and it
worked well otherwise.

Any thoughts on what might be wrong, or how to go about analyzing this?
I'm hoping that it's just a display connector or something simple.

Cheers,
-Neil.

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2002\08\10@175040 by Spehro Pefhany

picon face
At 01:57 PM 8/10/02 -0500, you wrote:
>Got a Fluke 8060A DMM here, that has had an LCD problem since it was
>new.  The LCD display is dim, and over time has dimmed more to the point
>where it's almost gone.  I used to be able to see enough to use it, and it
>worked well otherwise.
>
>Any thoughts on what might be wrong, or how to go about analyzing this?
>I'm hoping that it's just a display connector or something simple.

Try carefully cleaning the zebra connectors and surrounding PCB with
alcohol. Look first for signs of electrolyte leakage from the e-caps,
replace if you see any.

Try the ratio self test, courtesy of Malcolm Moore:

-       hold the continuity/beeper button while turning meter on
-       keep it pressed until POST is complete (8.8.8.8. on display)
        and release
-       the meter should now read 10000 +/- 5 counts (decimal point
        is based on range switch and doesn't matter).

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
spam_OUTspeffTakeThisOuTspaminterlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
9/11 United we Stand

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2002\08\10@194416 by Jim Ewald

flavicon
face
Neil,

That might be an indication of weak batteries or a bad connector in the
battery circuit. My DMM does that before the low battery warning lights
up. Like I can see that when the display is almost completely gray. You
might also try re-seating the LCD connector cable. That's all I know to
try without a schematic.

Regards,
Jim

{Original Message removed}

2002\08\10@205515 by Reginald Neale

picon face
>Got a Fluke 8060A DMM here, that has had an LCD problem since it was
>new.  The LCD display is dim, and over time has dimmed more to the point
>where it's almost gone.  I used to be able to see enough to use it, and it
>worked well otherwise.
>
>Any thoughts on what might be wrong, or how to go about analyzing this?
>I'm hoping that it's just a display connector or something simple.

If it has a rechargeable battery, make sure the battery voltage comes
back to normal when you recharge it. I believe bad batteries can
cause display dimming and other problems too.

Reg

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2002\08\10@211558 by Randy Jones
flavicon
face
Neil,

I have a Fluke 87 DMM built somewhere around 1993 to 1995, and it
periodically needs repair for the same symptoms you described -- a gradual
"dimming" of the LCD display.  Maybe a better way to describe it is a loss
of contrast so that the numbers no longer appear different from the
background.

A couple Fluke reps at a trade show immediately knew the problem (guess it
was common) and showed me what to do.  The meter must be disassembled to the
point where the LCD glass can be removed.  There are a couple rubbery
components that are apparently the (non-metallic) conductors to the LCD
glass.  I'm not familiar with the construction technology, but they need to
be cleaned, perhaps with a swab moistened with alcohol.  They may have used
a pencil eraser, I don't recall at this point.

I just did mine a few minutes ago to prepare this response.    This is
probably the third time this repair has been needed.  The display had become
so faint that I haven't used it meter for some time.  I hope yours is the
same thing, and is as easy to perform as on the 87 (which is now working
fine once again).

Best wishes,
Randy Jones


{Original Message removed}

2002\08\10@212429 by Jinx

face picon face
> The meter must be disassembled to the point where the LCD
> glass can be removed.  There are a couple rubbery components
> that are apparently the (non-metallic) conductors to the LCD
> glass.

Zebra strips

Strange that this should happen to a quality product like Flukes.
I've used reasonable but cheap meters for years and never
needed to clean those conductors. Same with my VCR remote,
which has a programming LCD on it, and gets absolutely gross
inside with, well, ever cleaned out a remote control ? Ick ick ick

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2002\08\10@215013 by Jim

flavicon
face
What would a touch of "Caig" contact enhancer
do I wonder?

RF Jim


----- Original Message -----
From: "Randy Jones" <.....randyjonesKILLspamspam@spam@WORLDNET.ATT.NET>
To: <PICLISTspamKILLspamMITVMA.MIT.EDU>
Sent: Saturday, August 10, 2002 8:07 PM
Subject: Re: [EE]: Fluke meter LCD problem


> Neil,
>
> I have a Fluke 87 DMM built somewhere around 1993 to 1995, and it
> periodically needs repair for the same symptoms you described -- a gradual
> "dimming" of the LCD display.  Maybe a better way to describe it is a loss
> of contrast so that the numbers no longer appear different from the
> background.
>
> A couple Fluke reps at a trade show immediately knew the problem (guess it
> was common) and showed me what to do.  The meter must be disassembled to
the
> point where the LCD glass can be removed.  There are a couple rubbery
> components that are apparently the (non-metallic) conductors to the LCD
> glass.  I'm not familiar with the construction technology, but they need
to
> be cleaned, perhaps with a swab moistened with alcohol.  They may have
used
> a pencil eraser, I don't recall at this point.
>
> I just did mine a few minutes ago to prepare this response.    This is
> probably the third time this repair has been needed.  The display had
become
{Quote hidden}

it
{Quote hidden}

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2002\08\10@225943 by Tom Messenger

flavicon
face
At 01:24 PM 8/11/02 +1200, you wrote:
>> The meter must be disassembled to the point where the LCD
>> glass can be removed.  There are a couple rubbery components
>> that are apparently the (non-metallic) conductors to the LCD
>> glass.
>
>Zebra strips
>
>Strange that this should happen to a quality product like Flukes.

Yeah, it is strange but, well, you know, it's probably just a fluke.

Tom M.

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2002\08\10@231640 by Robert Rolf

picon face
Contact enhancers would probably make all the segments turn on because of
cross channel conductivity.
Could also cause the rubber in the Zebra stripes to break down in time if the
residue is the least bit oily (and most are, to act as an air barrier).

The impedances involved are so high, anything the least bit conductive will give
crosstalk. Be prepared to thoroughly clean off anything you apply if it
does mess up the display.

The long term problem with the displays may be inadequate clamping pressure.
It only takes a few mils error in thickness to go from manufacturer's spec
for pressure to 'too low to last'.

I had this problem (Z-sripe fatigue) with several Beckman DVM's back
in the 80's. Used a shim of paper under the plastic clamp to permanently
(more or less) fix the problem. That might be an option for the Fluke's
although the display clamp geometry is quite different.

Robert

Jim wrote:
>
> What would a touch of "Caig" contact enhancer
> do I wonder?
>
> RF Jim
>
> {Original Message removed}

2002\08\10@235357 by Randy Jones

flavicon
face
>Strange that this should happen to a quality product like Flukes.
>I've used reasonable but cheap meters for years and never
>needed to clean those conductors.

Yeah... I've been using my moderately cheap meters with no problem, waiting
for the motivation to dig into the Fluke.   Glad this message came along, I
have missed using it.

I still have some of the Caig stuff, from back when they called it
"Cramolin," but would be nervous about applying it to the Zebra strips.
Especially given the long intervals between needing repair.  In other words,
it isn't enough of a pain to justify the possible risk, in my mind anyway.

Can someone tell me what kind of conductor material is used in the Zebra
strips?  Some kind of carbon fiber or powder, maybe??

Robert,
I had a Beckman DMM in the very early 80's... HD-100 maybe?  It was the
first bright yellow "hardened" handheld DMM, as I recall.  The case halves
were o-ringed, and it was rated for a multi-foot drop to concrete, and
immersion in water.  It gave me many years of good use in a tough
environment (automotive electronics repair).  Eventually the LCD developed
the opposite problem as the Fluke -- the digit segments became dark even
when the meter was off, and they gradually bled until the whole display
looked like it was filled with black ink.  Would that indicate a change in
the spacing of the glass inside the LCD, or...???  Very nice meter, though.

Randy

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2002\08\11@002324 by Jim

flavicon
face
Found this on a web search:

  "Stabilant 22A"
  "Great for revitalization of LCD contacts"

www.micro-tools.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=MT&P
roduct_Code=22A-F

Perhaps this is a specific application only to the particular
LCD they refer to ... proceed at one's own risk!

RF Jim

{Original Message removed}

2002\08\11@005729 by Jinx

face picon face
> >
> >Strange that this should happen to a quality product like Flukes.
>
> Yeah, it is strange but, well, you know, it's probably just a fluke.
>
> Tom M.

Oh ha ha, very good. The act's really coming along Tom

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2002\08\11@015053 by Randy Jones

flavicon
face
Jim,

Well, I have some Stabilant 22A, and both it and the Fluke were "evaluation"
samples, so I guess I'm somewhat obligated to do some evaluation - heh, heh.

We had considerable discussion and correspondence with D. W.
Electrochemicals, the manufacturer of Stabilant, and I came away with a very
positive impression.  Stabilant has both a US patent and a NATO part number,
and many positive testimonials from heavy-hitter sources.  It is supposed to
be non-conductive other than when in direct contact with a conductor, so....
gulp... here goes....

I took the 87 LCD back apart, and applied a very light coat of Stabilant 22A
to the edges of the two Zebra strips which contact the main PCB.  The strips
were stuck fairly tightly to the LCD glass, and I wasn't comfortable pulling
them off -- not knowing whether they are supposed to be that way.  I seem to
remember them *not* being stuck to the LCD earlier, but don't want to risk
damaging anything.

Reassembled... and... ugh... display is scrambled.  But... the glass is
upside down.  Duh -- thought I was being careful to avoid that.  Flipped it
around and... beautiful.   Definitely no cross-talk between the segments.
The segments look darker than before, but I cannot be certain that the
Stabilant is the cause:

1)  Lighting conditions are a bit different than earlier when I first did
the repair.

2)  I disturbed the position of the Zebra strips again, which may have
affected the contact resistance.

3)  The influence of wanting a certain result?  I'm trying to avoid this,
but this is a subjective observation...

Bottom line, the Stabilant didn't hurt (so far) and may well have helped.
After completing the repair this afternoon, I was mildly disappointed at the
lack of contrast, but thought maybe my memory of the original appearance was
inaccurate due to the long time since the LCD has been working "as-new."
Now it looks like new again.  ...And if those three screws on the back would
just stop trying to get cross-threaded, I'd be really thrilled!

Oh... now I see why they're called "Zebra" strips.  Anyone know what the
conductive material typically is?

Randy


{Original Message removed}

2002\08\11@015959 by Spehro Pefhany

picon face
At 10:51 PM 8/10/02 -0700, you wrote:

>Oh... now I see why they're called "Zebra" strips.  Anyone know what the
>conductive material typically is?

Alternating layers of conductive and non-conductive elastomer, typically
silicone rubber. For LCDs, the carbon loaded stuff is okay (high
resistance). There are alternative types that have lower resistance
by the use of wires, but they don't seem to be very popular. I believe
they were invented by a Japanese company.

Personally, I prefer heat sealed flat cables for this kind of thing. The
pin type is okay, but adds considerable cost to the display in quantity
and constrains things mechanically.

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speffspamspam_OUTinterlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
9/11 United we Stand

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2002\08\11@022316 by Joe Farr

flavicon
face
I think the technical term your looking for is 'finger funk' :)
It's the same stuff that collects in computer keyboards, along with peoples dandruff.


{Original Message removed}

2002\08\11@024812 by Pic Dude

flavicon
face
> I think the technical term your looking for is 'finger funk' :)
> It's the same stuff that collects in computer keyboards, along
> with peoples dandruff.

... and the cat's hair.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2002\08\11@060410 by Roman Black

flavicon
face
Pic Dude wrote:
>
> Got a Fluke 8060A DMM here, that has had an LCD problem since it was
> new.  The LCD display is dim, and over time has dimmed more to the point
> where it's almost gone.  I used to be able to see enough to use it, and it
> worked well otherwise.
>
> Any thoughts on what might be wrong, or how to go about analyzing this?
> I'm hoping that it's just a display connector or something simple.


If the effect is uniform over the entire display
area you can probably rule out damage to the LCD
elements and crystal material itself. Most likely
the voltages going to the LCD are no longer correct.

Since this "faded" over time my guess would be any
caps in any inverter stages. That would be typical
from the ESR faults etc that occur with caps over
that time period. Check any electro caps in it,
even the circuit mount ones. The surface mount
caps in 10uF seem to fail a lot, they ooze a
fishy smelling liquid. :o)
-Roman

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2002\08\11@192538 by Benjamin Bromilow

flavicon
face
> 3)  The influence of wanting a certain result?  I'm trying to avoid this,
> but this is a subjective observation...

Aha, the eye of faith....

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2002\08\11@213240 by Spehro Pefhany

picon face
Again courtesy of Malcolm Moore, here is where you can get manuals for
the 8060A (hidden in "discontinued products" on Fluke's site)

  ftp://www.fluke.com/download/manuals/8060a_3vimeng0200.pdf
  ftp://http://www.fluke.com/download/manuals/8060a___imeng0300.pdf

There is fairly large trucking firm here that is called "Fluke Transport"/

Their slogan: "If it's on time, it's a Fluke".

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
@spam@speffKILLspamspaminterlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
9/11 United we Stand

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2002\08\12@120419 by Josh Koffman

flavicon
face
Personally I use Stabilant 22a quite a bit. It really is a great
product. I don't really know it works chemically, but it hasn't reacted
with anything I've put it on yet.

Just a satisfied customer,

Josh
--
A common mistake that people make when trying to design something
completely foolproof is to underestimate the ingenuity of complete
fools.
       -Douglas Adams

Jim wrote:
>
> Found this on a web search:
>
>    "Stabilant 22A"
>    "Great for revitalization of LCD contacts"
>
> www.micro-tools.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=MT&P
> roduct_Code=22A-F

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2002\08\12@160322 by Jim

flavicon
face
I've been using WD-40 on a variety of connectors
including those in RF applications (and this includes
the most demanding RF application: full-duplex
amateur repeaters equipped with GaAs FET RF amps)
for years now -

- including my Slot-1 Pentium PIII 500 MHz processor ...

I should probably get a bottle of Caig or Stabilant
instead!

RF Jim

{Original Message removed}

2002\08\12@220623 by Tom Messenger

flavicon
face
At 09:46 PM 8/11/02 -0400, Spehro wrote:
>Again courtesy of Malcolm Moore, here is where you can get manuals for
>the 8060A (hidden in "discontinued products" on Fluke's site)
>
>   ftp://www.fluke.com/download/manuals/8060a_3vimeng0200.pdf
>   ftp://http://www.fluke.com/download/manuals/8060a___imeng0300.pdf

Spehro, THANK YOU! for that tip on Fluke. Having gone through the front
door (dub dub dub....), I didn't find those files. But via ftp, there they
are. Got 'em, checked 'em out, fixed my meter.

Coool. I have a very old 8060A that had a leaky cap on the autozero portion
of the a/d circuit.  The pdf you linked to is very thorough and very
friendly about how to open, troubleshoot and close-up the meter.

Thanks again.
Tom M.

ps: don't hesitate to point out any other good test equipment manuals on
line if you know of any, like Tektronix, HP, or others.

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2002\08\13@120534 by Brendan Moran

flavicon
face
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

> The pdf you linked to is very thorough and very
> friendly about how to open, troubleshoot and close-up the meter.

This is why I really like Fluke.  The way that they expect you to
want to fix your own equipment, and seem to expect you to do so.  For
instance: the batteries are inside the main cover, not in a seperate
compartment.  There are no "do not open" or "no user serviceable
parts inside" tags.

- --Brendan

-----BEGIN PGP SIGNATURE-----
Version: PGPfreeware 6.5.8 for non-commercial use <http://www.pgp.com>

iQA/AwUBPVkt6QVk8xtQuK+BEQJNiwCgyLe3mG5S326JPVBRCaNMYlUKZj0AoL7f
1qsUI98CZeS26k1rU1hsBf37
=GnyW
-----END PGP SIGNATURE-----

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email KILLspamlistservKILLspamspammitvma.mit.edu with SET PICList DIGEST in the body


2002\08\13@124733 by Robert E. Griffith

flavicon
face
>> For instance: the batteries are inside the main cover

Huh, they have batteries?  I thought they ran on magic because mine has been
going for around 15 years without the batteries going dead.

Of course now that I have mentioned it, I am sure they are going dead as we
speak:)

--BobG

{Original Message removed}

2002\08\13@141557 by Benjamin Bromilow

flavicon
face
> This is why I really like Fluke.  The way that they expect you to
> want to fix your own equipment, and seem to expect you to do so.

They just want you to buy another DVM to mend it ;)

Ben

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email RemoveMElistservTakeThisOuTspammitvma.mit.edu with SET PICList DIGEST in the body


More... (looser matching)
- Last day of these posts
- In 2002 , 2003 only
- Today
- New search...