FLUKE 8024B 33 years old and still going strong! Beware 3MB Photos

[Spawn]

Here a teardown of a 33 years old Fluke 8024B, I was planning to do this for a while and I am now inspired by the topic of retiredcaps here


Without words…

[ModemHead]

Nice photos, thanks for posting.  First time I've seen inside that model, I find the two-board construction interesting.  That's a lot of big switches and through-hole components in a small space.  Same 7106-based chip (429100) as the 8020B.  What exactly does the Peak-Hold switch do?

[Spawn]

Thanks I am glad you liked it,
Peak Hold captures the highest value, this was the short explanation 

Here, longer version from the manual 

[lowimpedance]

Nice and 'minty', did you buy it when new?.
Fully 'accessorized' too with hard case verrrry nice.
Interesting the flex circuit looks the same as the one used in the 8020a to connect the LCD to
the main board, (they did away with that for the b revision).
I noticed the unit only uses 1 miniature electrolytic, keep an eye on that.
They have a tendency to leak with the usual corrosion result.
I have a number of this series (8020b *2 and 8062a) which have all suffered major damage
due to these rotton caps.

[retiredcaps]

Here a teardown of a 33 years old Fluke 8024B, I was planning to do this for a while and I am now inspired by the topic of retiredcaps here

Hi Spawn,

Thanks for the pictures. I appreciate it.

[Stephenniall]

I always thought these things were hideously ugly, But they're built so well.

Great Pictures, Thanks

Stephen.

[Spawn]

@lowimpedance, I was playing marbles or breaking my granddad’s radio when this was sold I think, since I was 7 back than

I got it second hand long time ago, it was really in bad shape, nothing broken but too much dirt, only thing broken was the Peak Hold button, a small part of it was still in the case, so could glue it back together. Meter was full with dust inside and almost black outside, I don’t even want to mention about the case and accessories, manage to clean it in 4 or 5 hours, was really worth it. 
I check the meter time to time, I want to keep it nice as it is, and I need the original test leads still but will find it over the years.


@retiredcaps, you are welcome it was pleasure to take it apart again for the photo’s

@Stephenniall, when I was at school I didn’t like them either because of my laziness, the buttons and set them right before measuring something while we also had BBC clamshell multimeters with rotation switch which was a lot easier. But later over the years my respect start to grow on these.

[Jay_Diddy_B]

Hi,
Great pictures and a great meter !!

I don't think it is quite as old as you think. The date codes on the chips are 1985 vintage, so that puts the meter at about 27 years old.

I am big fan of these meters I have just finished the repair of 8060A.

Jay_Diddy_B

[Spawn]

Thanks I check the PCB and didn't see that 8507. Not smart of me.

[retiredcaps]

I am big fan of these meters I have just finished the repair of 8060A.

Would you mind sharing what you repaired with the 8060A?  I assume some of the caps spewed their guts?

[Jay_Diddy_B]

Hi,

Nothing too exciting. The board that was in the meter had suffered catastrophic failure in the area around the input circuitry. The catastrophic failure made the board slightly conductive. The meter would read 45M Ohms.

I tried to clean the board by scrubbing with IPA, but it could not be fixed.

What I can share is a process that I have been working on the reverse the yellowing of the cases. This was inspired by the Commode computer fans ans something called 'RetrObright'.

Link: http://www.lemon64.com/forum/viewtopic.php?t=30892

My process is much simpler. I soak all the plastic parts except the buttons in Hot water and Oxy Clean over night.

DO NOT soak the buttons. They change color. Don't ask me how I know 

This is what the Oxy Clean product that I used looked like:


This is the case before:


This is the process in action:



I don't have an after shot because it is difficult to capture the color accurately. But most of the yellowing was gone.


Try this at your own risk.

Jay_Diddy_B

[Spawn]

My 8024B came in same color as yours and with a lot “hand” dirt on it, that color you got there when these models get old is very common indeed.

I am using this to get full color back:
http://www.disko.com//html-usa/page-big-1688.html

I am using it on every multimeter I got to clean to be honest.

[Skimask]

Didn't Dave say something about bromide-something in the plastic causing this discoloration over time in a recent episode somewhere?
(could I be a little more vague here?)

[Spawn]

I didn’t see that one, but the Disko roller cleaner I use bring the color back and makes it shine too.

[retiredcaps]

Didn't Dave say something about bromide-something in the plastic causing this discoloration over time in a recent episode somewhere?

It was in the Macintosh SE teardown.

[Skimask]

DOH...sure was.
Proof at least I was paying attention!

[njht4]

hi can anyone help,I have a fluke 8024a the interconnect strip is breaking up are there any spares about or another way to fix this meter.The. strip connects the two boards.thanks

[TerraHertz]

It was in the Macintosh SE teardown.

Also this. Probably the first mention:
Restoring discoloured ABS plastic
https://www.eevblog.com/forum/projects/question-restoring-sun-discoloured-abs-plastic/
  --> http://retr0bright.wikispaces.com/
      http://www.amibay.com/showthread.php?t=1480&page=4