Making an esr meter.
This is the schematics suggested to me in this thread:
https://www.electro-tech-online.com/threads/theory-and-repair-of-lcd-monitor.130015/
https://ludens.cl/Electron/esr/esr.html
**broken link removed**
This is my experimental implementation:
**broken link removed**
Transformer I made is autotransformer with 290 turns with a tap at 15 turns.
I shorted the leads input and set output current with trimpot to 100uA.
0R - 100uA
0R5 - 91uA
1R - 84uA
4R7 - 45uA
10R - 18uA
Measurements are taken with DMM with DC setting at 2mA.
So the values are probably mean value.
Also I measured output voltage at pin one of TL062 and I get 2.55V,
which is mean of square-wave 5V.
My question is about bogus readings when I measure with AC setting on my DMM.
I am attempting to measure output voltage of the transformer to figure out
should I rewind it.
But first to verifie I measured voltage from pin 1 after C2.
With DC setting on my DMM it measures 0 - OK.
With AC setting on my DMM,it measures 6.05 V -NOT OK
Since square wave integral is pi/2 bigger then sine integral,
I tried to do this 6.05*2/pi and it is 3.85 which also looks wrong.
So how should I interpret readings from my DMM when AC and
should I rewound my transformer?
Many thanks.
This is the schematics suggested to me in this thread:
https://www.electro-tech-online.com/threads/theory-and-repair-of-lcd-monitor.130015/
https://ludens.cl/Electron/esr/esr.html
**broken link removed**
This is my experimental implementation:
**broken link removed**
Transformer I made is autotransformer with 290 turns with a tap at 15 turns.
I shorted the leads input and set output current with trimpot to 100uA.
0R - 100uA
0R5 - 91uA
1R - 84uA
4R7 - 45uA
10R - 18uA
Measurements are taken with DMM with DC setting at 2mA.
So the values are probably mean value.
Also I measured output voltage at pin one of TL062 and I get 2.55V,
which is mean of square-wave 5V.
My question is about bogus readings when I measure with AC setting on my DMM.
I am attempting to measure output voltage of the transformer to figure out
should I rewind it.
But first to verifie I measured voltage from pin 1 after C2.
With DC setting on my DMM it measures 0 - OK.
With AC setting on my DMM,it measures 6.05 V -NOT OK
Since square wave integral is pi/2 bigger then sine integral,
I tried to do this 6.05*2/pi and it is 3.85 which also looks wrong.
So how should I interpret readings from my DMM when AC and
should I rewound my transformer?
Many thanks.
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