explain leakage like the resistance climbing or dropping?? should it check like an open circuit?
If there is leakage, the meter's display will change when you touch the probes to the transistor's leads. If there is no leakage, there may be a blip on the display but it will go quickly back to whatever the meter reads when the probes are in contact with nothing but air.
gotcha ill do that tomorrow afteroon when i get off work ill post my results , hopefully in a week or so ill have an oscilloscope (fingers crossed ) and thank you for your help so far
output Q410 legs 1-2 reads open 2-3 reads 1.7 mohm but now 300k leaking i assume legs 1-3 read open
Q 412 read open or infinite across all paths
Q411 reads same as Q412
Q413 reads same as 411 and 412
is is safe to assume Q410 is bad???
Q 412 read open or infinite across all paths
Q411 reads same as Q412
Q413 reads same as 411 and 412
is is safe to assume Q410 is bad???
Read the following page and test as shown in the FET section of the page.
Basic Amplifier Repair - Transistor Test Applet Link
Basic Amplifier Repair - Transistor Test Applet Link
first checked same as before , reading 11.16 megaohms on 2-3 on Q412 slowly climbing in value other check same as previous
Did you short pins 1 and 3?
Did you get OL with one probe orientation and a different reading with the probes reversed (2-3)?
Did you check it on diode check?
Were you touching any part of the transistor or the probes?
Did you get OL with one probe orientation and a different reading with the probes reversed (2-3)?
Did you check it on diode check?
Were you touching any part of the transistor or the probes?
Q 412 reads OL over all paths Q411 reads OL also Q413 reads 1.805 Mohms across 1-2 pins 2-3 10.5 mohms
Were you touching any part of the transistor or the probes?
It's going to be much more efficient if you answer all of the questions.
It's going to be much more efficient if you answer all of the questions.
pins were shorted with alligator test leads and i had the little tiny test clips on my probes to hold the transistors
i also did the diode check got .474 one way and 0.000 the other on Q410 the others tested .474 and OL
Q410 should be defective according to these tests the others not sure if .474 etc is an acceptable range since its below .5
0.4... is OK if the reverse is OL.
It's not possible to get 0.000 and 0.474 on a transistor between legs 2 and 3 with 1 and 3 shorted. Re-check Q410.
All should read OL on ohms and diode check between leg 1 and the other legs of any individual transistor (no jumper connected).
It's not possible to get 0.000 and 0.474 on a transistor between legs 2 and 3 with 1 and 3 shorted. Re-check Q410.
All should read OL on ohms and diode check between leg 1 and the other legs of any individual transistor (no jumper connected).
Although you should have infinite resistance there and this transistor may be defective, technically, I don't think that this would cause the problems you were having.
clip leads onto pins 1 and 2 and move the clips gently side to side. Do this without touching any metal on the leads/clips or on the transistor. Does the resistance ever change from OL?
Do this for all 4 FETs.
clip leads onto pins 1 and 2 and move the clips gently side to side. Do this without touching any metal on the leads/clips or on the transistor. Does the resistance ever change from OL?
Do this for all 4 FETs.
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