how to properly measure test points. 25inch k7400 chassi

jbaker

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how to properly measure test points. 25inch k7400 chassi

im trying to figure how to properly measure the 25k7400 test points

well gardner says voltages should be

with respect to ac ground

pin 103-320 mine is 71.6
pin 104-17.10 mine is 56
pin 105-0.90 mine is 72
pin 106-1 mine is 0

with respect to chassi ground
pin 200-4.80 mine is 4.9
pin 201-0.10 mine is 1
pin 202-117.20 mine is 119 is B+ I believe
pin 203-152 mine is 153
pin 204-14.70 mine is 14.7
pin 205-24.50 mine is 24.5

I used a cheap harbor freight red meter set to 200vdc
did I possibly measure pins 103 thru 106 wrong I used the black pin on the connector as ac ground was that the wrong pin to use I have white black and green wires on the power connector
pins 200 thru 205 was grounded to the chassi those came out with almost perfect readings

well anyway it still plays blind with sound no neck glow or static from tube I never saw the tube work I was just taking a chance that it would work. is everything measured in dc volts? this is a brand new 25k7400 chassi I bought on this site. possably a bad tube? it had a u5000chassi and WG2550 tube in it that didn't work so I bought a new chassi and that didn't work either :(

any help appreciated thanks guy's
 
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Active - White
Neutral - Black
Green - Earth

If the voltages are w.r.t. "ac ground" then you should be measuring AC, not DC. Please note that it's spelt chassis.
 
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ok so I will test with the white as netural and set the meter to ac. see what I get thanks
 
when you measure voltages prior to the transformer, AC voltages, you use the ground side of the biggest cap on the chassis....that is the proper ac ground.
 
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