My new to me 8840A

[smason]

Just a quick report on my 8840A.


Compared to my 87-IV both meters read the same on DC volts from my lab supply. My 77 was reading a bit high so I tweaked the adjustment pot at 3.0000 V according to the 8840 and now it seems accurate as well.

The calibration sheet for my voltage standard says the DCv is 5.0000v and by golly all of my Flukes agree.

This is not a calibrator or any provable true standard, just a "pretty damn accurate" standard measured with a really calibrated meter at time of build.

I was going to set up a photo of all 3 flukes, a Micronta and a 1 hung low DMM and 2 Micronta analog meters all measuring the same voltage, but I don't have the time or patience to get all of that happening on my very messy bench, so here are the 3 Flukes connected to the voltage standard.

DC milliamps also look pretty accurate on the 8840 and the 87. Looks like my 77 has a blown fuse (who knew?)

Resistance is off by .0002k or so, but I didn't spend any time waiting for settling or writing down accurate readings, nor do I know what the ambient temp is. My calibration sheet on the resistances was at 69F.

Suffice it so say, for my purposes any of my Flukes are accurate enough and then some.

[retiredcaps]

Re: My new to me 8840A

Hi Smason,

The 8840A looks great.

It looks like your 77 might have some faded lcd segments? If yes, take it apart and clean the elastometers and pcb connectors with a qtip dipped in isopropyl alcohol.

[smason]

Re: My new to me 8840A

Hi Smason,

The 8840A looks great.

It looks like your 77 might have some faded lcd segments? If yes, take it apart and clean the elastometers and pcb connectors with a qtip dipped in isopropyl alcohol.

Yeah I'm loving the 8840 so far. Not that there's anything wrong with my 87, I just got it into my head that I wanted a bench meter. I may have a problem developing.

As for the 77 I think in this case it's just bad light/angle.

It DID have a problem a couple years ago.
It involved a fight between 2 cats and some very smelly output that leaked into the meter. I had no idea for months, till I went to use it.

I cleaned the elastomer, and I think I actually sanded down and tinned the corroded PCB with solder to get it to work at all.

[modemhead]

Re: My new to me 8840A

It DID have a problem a couple years ago.
It involved a fight between 2 cats and some very smelly output that leaked into the meter. I had no idea for months, till I went to use it.

Your 77 has no CAT rating. Therefore you must keep it away from cats.

[smason]

Re: My new to me 8840A

Your 77 has no CAT rating. Therefore you must keep it away from cats.

ROFL!!
Well it's a cat-free zone now.

[smason]

Re: My new to me 8840A -and voltage standard info

Hi Smason,


It looks like your 77 might have some faded lcd segments? .

So that's been in the back of my mind all evening. I've been thinking, "well, Retiredcaps REALLY knows his meters, so he's probably right"

So I had to go check. Decided to replace the fuse too.

Happy to report that the display is fine. I looked at the back of the meter, 630ma fuse. OPened my fuse drawer. Had a bunch of packages of Buss fuses (you know the plastic and aluminum 5 in a pack ones) and no 630s.
Then I spotted a ziplock baggie with about 15 of them in it, labelled 630 ma Fluke. I must pop a lot of fuses

Oh, forgot to mention, my voltage reference is a DMMCHeck from voltagestandard.com Great little unit. Not as nice as DAve Jones' EDC Voltage standard, but certainly good enough for many people.

[retiredcaps]

Re: My new to me 8840A -and voltage standard info

So that's been in the back of my mind all evening. I've been thinking, "well, Retiredcaps REALLY knows his meters, so he's probably right"

I learned a lot from modemhead's blog and forum posts. Modemhead knows way more than I, but I'm going up the hockey stick curve fast though.

In the photo, it looks like a couple of segments were dim, but you have the best view. I had a couple of 70 series multimeters that had 1 or 2 dim segments.

Then I spotted a ziplock baggie with about 15 of them in it, labelled 630 ma Fluke. I must pop a lot of fuses

You probably have over $100 worth of fuses in that drawer. I have yet to blow a fuse. I have purchased "working" multimeters with blown fuses or the odd bolt in it acting as a fuse.

Modemhead took one apart if you want to see the insides

http://mrmodemhead.com/blog/inside-a-multimeter-fuse/

Oh, forgot to mention, my voltage reference is a DMMCHeck from voltagestandard.com.

If I had one, I would be using the voltage reference that would give me the most amount of resolution. A 1.5000 reference would let me check out an extra digit on the Fluke 87V in high resolution mode and 3 decimal places on the 70 series.

[smason]

Re: My new to me 8840A -and voltage standard info

You probably have over $100 worth of fuses in that drawer. I have yet to blow a fuse. I have purchased "working" multimeters with blown fuses or the odd bolt in it acting as a fuse.
If I had one, I would be using the voltage reference that would give me the most amount of resolution. A 1.5000 reference would let me check out an extra digit on the Fluke 87V in high resolution mode and 3 decimal places on the 70 series.

No way I paid anywhere near what the fuses go for these days. I have no idea when I purchased them, but I'd guess mid-80s. Probably from B&E or somewhere local (Not Active)

Yes 1.5v would give another digit of accuracy. I chose the DMMcheck because it had dcv dcma and 3 precision resistors.
Initially I was going to make my own, but after thinking about designing and etching a pcb, and the amount of work, and no way to calibrate it, I got lazy

The Pentaref from voltagestandard.com was my second choice, but it was almost twice the price.

[modemhead]

Re: My new to me 8840A

The little ceramic 630mA fuses in the 77 are not quite as expensive as the larger fiber-tube ones, fortunately.

The DMMCheck is incredibly useful and much easier/better than a homemade solution, but as noted, 5V is not the most convenient number for models where 1, 2, 3 or 4 is the maximum most-significant-digit. Playing with older 2000-count and 20,000-count meters like I often do, I find myself in need of a 1.9V reference.

I may have to pull the trigger on one of those Pentaref gadgets. Unless of course the tooth fairy drops a Fluke calibrator in my lap...

[Kiriakos GR]

Re: My new to me 8840A

Unless of course the tooth fairy drops a Fluke calibrator in my lap...

You are making more wild dreams than what usualy I do. LOL

[retiredcaps]

Re: My new to me 8840A

@smason. I forgot to ask if Canada Customs dinged you for any extra charges? Last year, my biggest purchase was $120 USD off ebay (USA) and I did not pay any duties or tax.

[smason]

Re: My new to me 8840A

@smason. I forgot to ask if Canada Customs dinged you for any extra charges? Last year, my biggest purchase was $120 USD off ebay (USA) and I did not pay any duties or tax.

This one was shipped with the new(ish) Ebay "“Global Shipping Program”
I knew nothing about this program until after this deal, nor did I realize it was shipping this way. I thought he was using USPS.

Apparently it's a system run by Pitney Bowes, but they use multiple carriers.
Very odd really.
http://pages.ebay.ca/shipping/global...buyer-tnc.html

Funny the seller didn't understand it either.
I got this from him:

Typically I send an invoice to the winning bidder of my items. Today I click on "send invoice"
and the following is what I got from eBay you can't send invoice for this order
"The item(s) will ship using the Global Shipping Program. As part of the program, buyer directly pays
international shipping and import charges to the third-party shipping provider.
The buyer will still be able to complete checkout even if you don't send an invoice."

So who is the shipper, how does the item get to the shipper? How do they know size of the box or weight?
I typically ship usps internationally, and they pick up?

So I sent him the link to the Ebay Global Shipping Program.

Anyway they did ding me about $30.00 in fees. Part of the problem was I did most of the tranaction on my cell phone and my eyes aren't as good as they used to be, I just clicked checkout and didn't see the $30.00 until much later.

Tracking was useless, it said it went from Georgia to Kentucky in a day or 2, then never updated after that. One day the track item link disappeared from the item on My Ebay, and co-incidentally the same day it came to my door via Canada Post. I know Fedex was involved at least briefly.

Lately almost all of my USPS/Canada post orders have not had any charges. used to be it was $5.00 or so. Fedex and UPS gouge you unless it's one of the more expensive priority options, then there is no fee.

[retiredcaps]

Re: My new to me 8840A

This one was shipped with the new(ish) Ebay "“Global Shipping Program”
I knew nothing about this program until after this deal, nor did I realize it was shipping this way. I thought he was using USPS.

I saw an auction about 3 weeks ago using the Global Shipping Program. After I read the details and saw a few other auctions, I decided that the pricing and fees were ridiculous compared to "normal" USPS shipping.