EEVblog Electronics Community Forum
A Free & Open Forum For Electronics Enthusiasts & Professionals
Welcome,
Guest
. Please
login
or
register
.
Did you miss your
activation email
?
1 Hour
1 Day
1 Week
1 Month
Forever
Login with username, password and session length
This topic
This board
Entire forum
Google
Bing
Home
Help
Search
About us
Links
Login
Register
EEVblog Electronics Community Forum
»
Electronics
»
Beginners
»
What are these?
« previous
next »
Print
Search
Pages: [
1
]
Go Down
Author
Topic: What are these? (Read 1452 times)
0 Members and 1 Guest are viewing this topic.
deandadnaed
Contributor
Posts: 12
What are these?
«
on:
April 07, 2019, 04:55:21 am »
Hi! I’m trying to find the tracks within a PCB. But I’ve got no idea what are these components.
Does anybody know what are they?
Enviado desde mi iPhone utilizando Tapatalk
Logged
OwO
Super Contributor
Posts: 1250
Country:
RF Engineer.
Re: What are these?
«
Reply #1 on:
April 07, 2019, 04:57:08 am »
Potentiometer.
Logged
Email: OwOwOwOwO123@outlook.com
Brumby
Supporter
Posts: 12380
Country:
Re: What are these?
«
Reply #2 on:
April 07, 2019, 06:50:14 am »
Trim pots to be more precise.
They are adjusted by a small flat blade screwdriver via the slot in the middle.
From the numbers on them, the resistance of each are:
103 = 10K ohm
202 = 2K ohm
503 = 50K ohm
Edit:
They are placed in circuits that need to be adjusted when they are first built and tested. Once adjusted, they should not need any further tweaking in normal service. Translation: Don't fiddle with them unless you know what you are doing and why.
«
Last Edit: April 07, 2019, 06:53:34 am by Brumby
»
Logged
Jwillis
Super Contributor
Posts: 1716
Country:
Re: What are these?
«
Reply #3 on:
April 07, 2019, 06:56:57 am »
Like Brumby says. But in addition The first 2 numbers times the multiplier. 0 = 1 , 1=10 ,2=100,3=1000,4=10000 ,5 =100000. So the top left is 10 times 1000 or 10000 ohms or 10K Ohms.The top right is 20 X 100 or 2KOhms and so on
Logged
deandadnaed
Contributor
Posts: 12
Re: What are these?
«
Reply #4 on:
April 07, 2019, 06:58:19 am »
Thank you very much!
Enviado desde mi iPhone utilizando Tapatalk
Logged
Brumby
Supporter
Posts: 12380
Country:
Re: What are these?
«
Reply #5 on:
April 07, 2019, 06:59:38 am »
If you're tracing out the circuit, the bottom two connections are fixed to each end of the resistance track. The third connection comes from the moving contact which is connected to the tag at the top.
Logged
digsys
Supporter
Posts: 2209
Country:
Re: What are these?
«
Reply #6 on:
April 07, 2019, 08:40:06 am »
... and those look like a ceramic type, which are much higher quality / grade than the "standard" plastic types.
Logged
Hello <tap> <tap> .. is this thing on?
deandadnaed
Contributor
Posts: 12
Re: What are these?
«
Reply #7 on:
April 08, 2019, 05:27:36 am »
Thank you. I’m trying to trace the circuit. I won’t be messing with the trim pots but I’ve measured them as they were set, just in case.
Enviado desde mi iPhone utilizando Tapatalk
Logged
Smokey
Super Contributor
Posts: 2895
Country:
Not An Expert
Re: What are these?
«
Reply #8 on:
April 08, 2019, 11:04:02 am »
For example (Tried to find pots that look like the ones in the pictures. Don't buy these specific ones, they are obsolete):
https://www.digikey.com/product-detail/en/bourns-inc/3319P-1-102/3319P-102-ND/612867
https://www.digikey.com/product-detail/en/panasonic-electronic-components/EVN-65AA00B23/K4A23-ND/6092
Logged
Print
Search
Pages: [
1
]
Go Up
« previous
next »
Share me
Smf
EEVblog Electronics Community Forum
»
Electronics
»
Beginners
»
What are these?
There was an error while thanking
Thanking...
EEVblog Main Site
EEVblog on Youtube
EEVblog on Twitter
EEVblog on Facebook
EEVblog on Odysee