FLUKE 8040A - Page 1
Forum section: electronics / testgear

author: almarghi
author_rank: Newbie
timestamp: January 05, 2018, 08:13:45 am
content: Hi everyone.I was surprised to see that there are almost no posts about the Fluke8040 multimeter. As I see it, it's an amazing piece of work. I have bought mine from ebay a while ago, and I am still admireing the old school, true engineering inside. Mine had still the original batteries inside, unusable though, but very nice.I have replaced them with 2 pcs. of paralleled Li-ion cells and had to add a charging module and a converter to 5V. It's a bit noisy so I'll have to put it in a shielding metal enclosure.Fortunately I could manage the changes without major intervention in the schematic and, most important, the pcb.C28&C29 had to be changed and moved to get the converter pcb in. S11 had to be opened permanently with a piece of plastic (it's under the charging/protection pcb.The charger used is a normal 5v wall adapter.In the attachments you find some photos , including changes made in the supply circuit.

author: Electro Detective
author_rank: Super Contributor
timestamp: January 05, 2018, 10:17:25 am
content: There are a few 8050A fans here like memine is a mains unit for bench use, so no batteries or charging to think aboutThe 8040A display looks great and would look even better parked on top of an analogue Tektronix CRT beastThere are few 8040A units going on Ebay at the moment

author: Fungus
author_rank: Super Contributor
timestamp: January 05, 2018, 10:33:34 am
content: https://www.ebay.com/itm/181794762166

author: Jeroen3
author_rank: Super Contributor
timestamp: January 05, 2018, 10:35:01 am
content: Can it function without the batteries? I have an 8050 collecting dust.

author: retiredcaps
author_rank: Super Contributor
timestamp: January 06, 2018, 01:51:25 am
content: Quote from: almarghi on January 05, 2018, 08:13:45 am?https://www.eevblog.com/forum/testgear/fluke-8040a-let%27s-take-it-apart-(and-see-if-we-can-fix-it)/

author: almarghi
author_rank: Newbie
timestamp: January 06, 2018, 07:55:34 am
content: I said "almost". In those photos is a Sabtronix, not a 8040

author: Electro Detective
author_rank: Super Contributor
timestamp: January 07, 2018, 10:07:43 pm
content: Quote from: Jeroen3 on January 05, 2018, 10:35:01 amIIRC, there were two 8050A types,mains only like mineand a mains charged batteries version which I assumed worked on mains too whilst charging the batteries, but may be 100% wrong on that

author: xwarp
author_rank: Frequent Contributor
timestamp: January 07, 2018, 11:16:03 pm
content: 4 sub C ni-cads will fix the battery issue with an 8050A.

author: edavid
author_rank: Super Contributor
timestamp: January 08, 2018, 12:12:05 am
content: Quote from: Jeroen3 on January 05, 2018, 10:35:01 amThis thread is about the 8040A, for which the answer is yes, but you need an external DC supply.It's not very practical for bench use, since it has the input jacks on the side.More of a curiosity than anything.But props to the OP for taking the trouble to replace the batteries.(Front panel photo attached, for those who have never seen one.)

author: Fungus
author_rank: Super Contributor
timestamp: January 08, 2018, 01:19:29 am
content: Quote from: Electro Detective on January 07, 2018, 10:07:43 pmIt seems unlikely that it wouldn't work on mains power.

author: edavid
author_rank: Super Contributor
timestamp: January 08, 2018, 02:50:56 am
content: Quote from: Fungus on January 08, 2018, 01:19:29 amThe battery version of the 8050A works on line power, but only if there are somewhat working batteries installed. If the batteries are removed or open circuit, it won't work.The 8040A will work even without batteries installed.

author: jh15
author_rank: Frequent Contributor
timestamp: January 12, 2018, 02:42:46 am
content: I have one I spotted recently in my basement, used to repair them, but only remembered difficult but clever construction. Not sure if an A model.Like all the greybeards here (not a virgin) I think I'd like it to light up my bench.Maybe put it along my nixie test gear. Don't trash your gear for nixie clocks, fix them!