Welcome to ITTSB Forum, extension and content sharing platform of ITTSB.EU ( Electrical Test and Measurement Product Reviews Blog ).

Registration this is Free, to support this Blog please use our donation links available in our Blog page and forum.  

Active since 7 June 2012  

Copyright Notice:  All content of this web site this is copyright protected. - Forum search engine this is disabled for Guests.  

Recent Posts

Pages: 1 2 3 4 5 6 7 8 9 10
This topic it is relative to Siemens (Thomson)  M273-A1 that is analog measuring  Low-Resistance device of 1983.

Siemens (Thomson) M273-A1 this is actually a resistors bridge this also using Thomson test leads connection which this is no other than more known Kelvin clips (four wires measurement).
This has three measuring ranges,  single knob at this device this is mechanical ranges selector, among push button (test start) and also this push button unlocks range selector when we need to move- up or to a lower range.

Accuracy specification this is 1.5% for it first measuring range that is from 200 micro-ohm up to 2.2 milliohm.
Other four higher ranges they are at 1% and measuring unit this is milliohm. 
2... 22 mΩ
20... 220 mΩ
200... 2200 mΩ

Specific made by Siemens meter, this using internal constant current source (circuit) so to inject DC current of 2A in to the test circuit.
This is a very high current which is designed to be used exclusively for wiring testing.
Practically Siemens (Thomson) M273-A1 this is first portable wiring testing meter which designed to serve in the application of troubleshooting telephone wiring connections at 1980 ~ 1990.

Picture of original test leads harness this is impossible to be found.
But even so,  my very own composed Kelvin clips to banana plug (test leads harness), this is not far away from what you do need as test leads for one M273-A1.

I am now owning my Galaxy S5 for 2.4 years,  I do not feel comfortable of me acting as beta tester at hundreds of small apps created every day.
But I have few small free apps to suggest because they use on-board sensors of S5 for delivery of productive features.

Build in sensors at  Galaxy S5 it makes it work as reliable compass (Magnetometer) and also as Clino-meter + bubble level.

My latest discovery helping me for Chinese to English (Off-line) translation due camera recognition, Chinese text over machinery this is not a problem any more.
(do not forget to download entire number of off-line data packages found at settings menu).   
When you use your smartphone mostly for business, increased security of your phone content it should bother you.

Unfortunately Android operating system this was full of security holes by design.
Google, Samsung, advertisers, software developers, all wanted to have access at your personal data = Your phone list, your Geo-location data (GPS recorded travels), your habits, your friends, products that you use, social media engagement, WiFi spots which you get internet access ( another way for  Geo-location data collection).

For me which I have awareness that Android operating system this is 100 times more insecure than my Windows XP Pro desktop computer, I did the wise thing to not use my smartphone as portable computer, but exclusively as phone which has few apps which they offer something productive or basic entertainment.

First App which I will recommend so any one to understand which apps transfer data with out your awareness this is:
NoRoot Data Firewall      https://play.google.com/store/apps/details?id=com.jianjia.firewall

My second recommendation would be:
Permissions Manager https://play.google.com/store/apps/details?id=com.hr.permissionsmanager
(discover which apps they have access at the hardware of your phone)

Third and last important recommendation this is navigation software unrelated with Google engines (Off-line use):
MapFactor GPS Navigation Maps  https://play.google.com/store/apps/details?id=com.mapfactor.navigator
Samsung S5 G900F this is smartphone which I truly love and respect because this was made to survive also at outdoor use.
I did put together few tips for you whom care to keep this phone alive and kicking for several years ahead.  ;)

Samsung S5 User manual does not say much about tips that any user he is obligated to do as maintenance in favor to proper waterproofing.

1) It does not say … DO NOT remove the back cover with out a good reason. (plastic hooks over the cover goes bad after 50 removals)
2) It does not say … Add baseline over the back cover O-ring every six months.
3) It does not say … Use microfiber cloth to clean from dust and dirt entire surface at the back of the phone before you attach the back cover.
4) It does not say… Get a wireless S-view cover so to remove stress from the charging port.
5) It does not say … Keep your own charging cable in to a dust free environment and away from your food.
S5 charging port this is protected from dust and pollution by it own protection cover, but power cables plugs get dirty if you are not careful enough, due such a cable you do transfer dirt at the charging port.

S5 G900 this is safe from water if you do all above, and never replace it screen at unauthorized service center (Original screen shields intact).
Practically, if you do all above and add also one Nillkin H+ tempered class over the screen, the phone becomes strong as fortress and water proof as submarine.
Original S5 back cover it is a poor choice but Samsung did it to keep this phone slim.

Original S-View cover this deliver lots of protection but the wireless charging version it is by far most wise selection.
With all above in mind phone electronics will stay healthy for decades, except if you are using S5 for navigation and this is exposed to enormously high temperatures under the sun in your car.

Historical facts: 
Samsung Galaxy S5 G900 this is considered today by Samsung as EOL  (end of life) product.
Security updates for Android 6.0.1 these now are available only once per year.

Latest version of Samsung firmware for Europe , now aloud you to disable several build in apps.
Most Google related apps can be now disabled.
Several Samsung apps can be now disabled too.
In simple English, finally after several years you may have full control over your phone by this running stock operating system.   
I came across a solar powered toy this operating with QXS521 controller.

Unfortunately QXS521 controller this is restricted to handle 1.5 Volt battery and voltage output.
There is no hope converting this so to handle several brighter 2.8V LED.
It can only power up a single LED due it current limitations, output this is square wave at 160KHz at 1.8V Max

Very specific toy this is terrible as lights source but still it is good enough as gadget to impress an five years old baby.
Internal battery this is Ni-mh 1.2V 40mA.   

Working voltage: 0.7V~1.5V
 Input current: 1.2V / 22mA (47uH)
 Input current: 1.2V / 16mA (68uH)
 High efficiency: 84%
 Internal integrated light switch
Recently I did purchase quantity of DPST Rocker Switch (with neon light).
Manufacturer web-page informs of initial contacts resistance 50 milliohm Max.

Generally speaking there is no handheld multimeter with necessary measuring range and four wires measurement capability.

I did my first evaluation at my new quantity of Rocker Switch by using the workhorse named as HIOKI RM3542A.
My findings they are very interesting, all three switches they did come close to 8 milliohm at both contacts (pairs) as soon I did repeat about 15 times the On-off process.
Worst milliohm resistance was measured at 38 milliohm and after these 15 work cycles all products they improved their conductivity down to 8 milliohm.

Pricing and dimensions or RM3542A they are both a problem and alternative solution much friendlier this is no other than Brymen BM878.
Brymen BM878 this comes also with a special function named as Earth continuity Test.
Resistance range this is up to 2 Ohm, 1 Ohm measurement this includes five digits resolution and 10 milliohm measurement this is possible.
With proper zero-out at Brymen BM878 the measurement it is very close to RM3542A.
Hundreds Asian sellers they present at their listings pictures in which ETA electronics test accessories logo this is clearly visible.

Who is then ETA electronics test accessories ?

Believe it or not ETA electronics test accessories this is a book, a products catalog, its not a brand or a factory nor a company that you can touch or see.
Practically this is a tool for Asian re sellers to gain access to products stock.
Naturally there is a website somewhere so registered trading members to be able to obtain nice and shiny product pictures for their listings, but eventually there is no access for us westerns to it.

In simple English what to we have here this is Asia to Asia B2B tool and foreigners are not welcome due Internet. :)

End of story.  :(

Second received  BOCHEN WXD3-13 (this send to the seller directly from the factory ) this also have defects, at single travel one direction run this has one issue, at reverse direction in two spots moving parts they are scratching it other.

In conclusion: BOCHEN  factory work this is a bad joke, if you need such potentiometer give your vote to Bourns alternatives.

Today I did receive long waited news.
GW Instek sends a picture this illustrating battery spare part.

Yes the battery comes bonded over aluminum frame, this solution translates that you are not simply paying for battery cells.

There is also a note, that its customer he should mention serial code number, because there is two versions of this spare part.
Currently available it is this pictured below.

Never forget that for actual pricing estimate, you should contact national GW Instek authorized re-seller.

My very own price estimate this is 80 Euros (plus 5 EUR local shipping) or a total of 85 EUR delivered.

This solution it is for customers willing accepting the risk to fiddle with sensitive ribbon type cabling and to perform free of mistakes work.
It looks like that we do not live in to a perfect world.   :D

3590S which I received this is stamped as Bourns and works great, actually I did use it at my LM317 project

From the other hand, BOCHEN WXD3-13 that I got it is an BOCHEN WXD3-13, at my first test at about 2/3 of inner parts travel I did spot mechanical noise an very specific setting.
While this potentiometer it does work,  this incident of moving parts to scratching it other it did alert me and I asked from the seller for a new replacement.
I am currently waiting for new replacement so to make my mind regarding bellow questions.

a) Did I receive a bad apple ?
b) Are these apples problematic due product design or due poor quality control?

Currently I do assume that in about ten days I will have my answers.

Pages: 1 2 3 4 5 6 7 8 9 10


Blog YouTube facebook twitter PayPal Donate Link

ITTSB Blog Sponsors

protosnet.com - Internet solutions

2017 Review samples received by

HIOKI EE Corporation - Japan Times Electronics ltd UK Vishay Foil Resistors POWERTRON resistors - VPG DER EE Electrical Instrument Co., Ltd.