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my 35 year old analog multimeter suddenly packed up?
There is no continuity on several cylindrical parts with coloured stripes on them, transistors??. 1 Diode "D1" does not test either.
Is it possible to identify the parts I marked with red dots in the foto attached so that I can order them from somewhere in the UK. I do not know where from either.
Thank you
There is no continuity on a few small cylindrical parts no
Comments
3 years ago
Meters these days are really cheap. Buy a reasonable digital one - it will be worth it.
Answer 3 years ago
All answers were helpful, thanx a lot, this subject is now CLOSED.
I could not find a place to click SOLVED.
3 years ago
If you are up for the challenge and you're looking for resistors, I would get them from aliexpress.com (if you're not in a hurry), they are really cheap and I have not had any problems with them.
https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20170902133726&SearchText=resistors
3 years ago
R5= red-brn-blk= 210= 21 ohms 1/2watt or red-brn-grn= 215= 2100000= 210 K
R2= brn-blk-blk= 100= 10 ohms 1watt
R6= red-grn-brn= 251= 250 ohms 1/2watt
R12= red-blk-blk= 100= 10 ohms 1watt
R13= pur-grn-blk= 750= 75 ohms 1watt
R17 can't make out the colors
Answer 3 years ago
I don't think he needs all them I think he just needs R9 unfortunately it is so badly burnt you can't read the color code.
Answer 3 years ago
Thank you, firstly what actually are they, transitors?
What exactly is the method of reading these, e.g R13 you read as "pur-grn-blk, how about the Yellow & Blue bands I can see also on it.
Which end does one start reading from?
Answer 3 years ago
Those are resistors. Transistors have (usually) 3 leads, whereas these only have 2. The colored bands are to identify the resistance.
To read, there is a color pattern. To remember, I start with Black, then Brown. I don't really have a trick to remember these, so you just have to practice. Then comes the middle colors. I remember these with a name, Roy G. Biv - Red, Orange, Yellow, Green, Blue, Indigo (not used), Violet. Then after that, there is Gray and White, and as with Black and Brown, you just have to remember. Then you have Gold and Silver. These are only used for the last band, so you know to start from the other end. The Gold and Silver are used to indicate the tolerance, or accuracy to the rated value.
The first two bands are the values, then the third is the multiplier (for a 4 band resistor). The last is the tolerance.
Answer 3 years ago
https://en.wikipedia.org/wiki/Electronic_color_code#Resistor_color-coding
Answer 3 years ago
Really confused now.
Sorry to bother you all, perhaps this is not for me. I'll just bin the meter.
Answer 3 years ago
Perhaps, instead of throwing your meter away, you could give it to someone who knows how to fix things?
Answer 3 years ago
I'm sorry. As you might have been able to tell, I'm not the best teacher.
Best of luck, though!
Answer 3 years ago
They are resistors measured in Ohms
Since China got into the game things are a bit more confused.
I try to read the side furthest from the tolerance gold or silver band.
The thing to remember is the last digit is the number of zeros.
See the picture and if you want there is a snappy mnemonic to remember the color order that most engineers know.
Answer 3 years ago
Here is a nice water analogy of of electricity.
Voltage (volts) is like pressure, Current (amps) is like water flow and Resistance (ohms) is like a constriction in a pipe.
And you get to see what a Zener diode can do to regulate pressure err voltage..
Simple math (V=I x R) Resistance multiplied by Current I equals Voltage...
3 years ago
You can get a new digital or a analog multimeter from BangGood for as little as 3 EUR.
https://www.banggood.com/?p=XR20127277342014082Z
Just enter Multimeter in the search.
You can also get the resistors from them also but chances are the parts would cost more than the meters for 3 EUR.
3 years ago
Where exactly can O buy these from?
Answer 3 years ago
Harbor Freight
https://www.harborfreight.com/7-function-digital-m...
under $7
Answer 3 years ago
Thanx icing, bough this one last week & it does not work at all.
I am in the UK, & was referring to where to get the Resistors.
Answer 3 years ago
rapidonline will have what you need in the Uk - https://www.rapidonline.com/
If not try Farnell
http://uk.farnell.com/
Answer 3 years ago
https://www.amazon.co.uk/s/ref=nb_sb_noss_2/259-46...
a new analogue meter will probably cast less than the parts.
3 years ago
What state is the fuse in ? Its the most likely part to have failed.
also worth looking at the back of the circuit board to see if there are broken or fused tracks, or bad joints there.
Failing all that, get to Maplin and see what they can offer. Its not likely to be resistor failure
3 years ago
rickharris, thank you but prefer the analogue ones , can't understand the digidal ones. My el. knowledge is very-very basic, only read continuity & mains or battery volts.
Answer 3 years ago
Trust the elder educator he was dragged into this digital age kicking and screaming like all of us were.. In the end you will like it...