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Can’t figure out textbook graphic.

DickFreed

Aug 6, 2021
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https://imgur.com/a/YJqSbIr

fig4-79.jpeg

The black slash i circled on protoboard was drawn in afterwards. Please ignore. I’m going to say multimeter is wrong, because of a short between rows of where the green and yellow leads are inserted from meter. But then the meter wouldn’t really be wrong then, would it? So I’m stumped.

Moderators note : uploaded picture and shows full size
 
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Kabelsalat

Jul 5, 2011
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You should re-draw / relocate the order of the resistors and assigning designators and numeric values so it gets manageable to work out the solution.
Just remember that on those kind of stripboards, the each coloumn are connected.
 

DickFreed

Aug 6, 2021
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You should re-draw / relocate the order of the resistors and assigning designators and numeric values so it gets manageable to work out the solution.
Just remember that on those kind of stripboards, the each coloumn are connected.
Looks like all resistors are in series to me, adding up to 108,000 ohms if I’m seeing colors correct. I hope you mean each column is connected as the board is oriented in the pic and not if it was turned 90 degrees. If any resistor was open, meter should read infinite resistance. I just don’t know.
 

AnalogKid

Jun 10, 2015
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The bottom left resistor is 10 K, not 80 K. 80 K is not a standard E-24, 5% tolerance value.

ak
 

DickFreed

Aug 6, 2021
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The bottom left resistor is 10 K, not 80 K. 80 K is not a standard E-24, 5% tolerance value.

ak
Hmmm, that would put the total at 38k. So if that 10k resistor was basically shorted within itself, the 27.8 ohm reading on the kilo range would make sense.
 

AnalogKid

Jun 10, 2015
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Except for a factor of 1000, yes. The display clearly indicates ohms with no multiplier.

Is the question oriented toward diagnosing a failed component? If so, the maybe kinda sorta changes everything.

ak
 
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