AVO Megger multimeters ???? - Page 1
Forum section: electronics / general

author: zaoka
author_rank: Frequent Contributor
timestamp: February 01, 2011, 04:09:13 pm
content: Just checking specification of AVO Megger M8037 multimeter, it refreshing analog bar 120/sec fro DC and ohm. Its way ahead of comeptition...Anybody know more about this company and its multimeters?Thanks

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: February 01, 2011, 04:52:10 pm
content: I bet that you love comparisons , but here you fall in a trap.The human eye , like the one that I have , actually I have two ,it needs 25 frames per second so to detect an smooth motion .Now what it will happen , if the projection of 40 refreshes per second ( of my Fluke 28II ) or the 100 refreshes per second,are detectable from your eyes , this is an subject that I have not explore .But you can , if you search for it , as subject .

author: Fraser
author_rank: Super Contributor
timestamp: February 01, 2011, 05:47:26 pm
content: AVO were a very much respected company in the days of large analogue multimeters. Under the name AVO-Megger they also have a good reputation for well built and accurate equipment.I own the 7029 as a back-up to my Fluke 87 III and I can advise that it is a very well built, solid, and accurate meter (within it's specification that is). Make sure it's specification and facilities meet your needs. I like the meter and for the price I paid, GBP30 for a 'new old stock' unit, I am very pleased with it.When comparing it to my AVO-Megger B131 LCR meter, I would suggest that they are from the same manufacturer and I understand the B131 is in fact an 'Escort' design rebadged by AVO-Megger and TENMA.Please be aware that AVO-Megger cannot supply schematics or spare parts for the 7000 series meters as they are not 'in-house' products.

author: Mechatrommer
author_rank: Super Contributor
timestamp: February 02, 2011, 02:33:41 am
content: Quote from: Kiriakos-GR on February 01, 2011, 04:52:10 pmanything flickering will make you headache (if you are sensitive guy), thats what i read and remember long time ago. anything faster than 25-30fps, you wont notice the transition, but you'll wonder the next morning why you have a headache when staring at something like monitor, screen etc. our brain will have a harder time "re-synching" to faster refresh rate, but not so fast, something like 30-75Hz iirc. Cheers mate, happy chinese new year

author: PetrosA
author_rank: Frequent Contributor
timestamp: February 02, 2011, 02:38:51 am
content: It sounds like there might be some confusion between updating the values and refreshing the LCD. I suspect the 120 times/sec DC/Ohm "refresh" is actually about the reading itself rather than the screen. A fast update speed will make it possible to detect spikes, dips etc. that a slower update speed might miss.

author: zaoka
author_rank: Frequent Contributor
timestamp: February 02, 2011, 02:58:11 am
content: Its just for analog bar, it updates aroun 120/sec.For the display it refresh every 0.2seconds as I remember. They claim it can detect noisy potentiometers etc... because analog bar is so fast..

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: February 02, 2011, 08:41:55 am
content: Quote from: PetrosA on February 02, 2011, 02:38:51 amThat's the base theory and commonly known.My point was clear ... and the simplified question would be : How many LCD updates per second are useful at the human eye ?I could possibly build my own DMM with 400 LCD updates per second , if the eye can not see that,then what I do its just to gain " positive impressions " ( marketing boost ) than offering an true valuable function.

author: metalphreak
author_rank: Frequent Contributor
timestamp: February 03, 2011, 03:53:34 am
content: There is persistence of vision which limits the effectiveness of higher updates per seconds. However, what if there is a spike in the reading that you are looking for? A slower updating meter might not display the spike at all, while a higher refreshing meter will, even if only for 1 "frame".

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: February 03, 2011, 08:18:02 am
content: I would fight the impressions with hard evidence ..Fluke says that an sampling rate every 100ms its more than enough to detect even spikes ..The 100ms stands for 10 updates per second.On the 28II it says that the bar-graph updates even at 40 times per second , this leads to the conclusion,that the sampling rate are close to 25ms = 4 times faster that what is actually needed.I do not remember currently the actual LCD refresh rate of the 28II that is slower than the speed of the IC that does the sampling in the measurement , I bet that I have to see Dave's review again so to refresh my memory .About the AVO , the number of 120 updates per second , leads to an sampling number, that looks ridicules tiny,and if it is true , I do not know who will get any actual gain from that.

author: Ernie Milko
author_rank: Regular Contributor
timestamp: February 03, 2011, 10:25:59 am
content: AVO also went through a phase of badging Metrawatt meters, circa mid-late 90s.The only picture I can find is this ebay auction:http://cgi.ebay.co.uk/150540004990

author: zaoka
author_rank: Frequent Contributor
timestamp: February 03, 2011, 04:18:21 pm
content: I missed their top of the line multimeter M3087 on eBay last nighthttp://cgi.ebay.com/AVO-MEGGER-M8037-PROFESSIONAL-MULTIMETER-/170595810093?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item27b84d7b2dI could test it and resale it...