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2250B is not powering on at all

I hope that these picture suffice. I will work on taking the measurements you requested. Thanks for your support.
 

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With power-on, you measured AC volts between sets of colored wires and got 0V for all?
Just to make sure, these are the wires coming out of the same side of the transformer, not the primary side?
I think there should be 6 wires ORG(2), WHT(1), YEL(2), BLK(1), GRN(2).
  1. Measure the AC voltage between the ORANGE wires. = 0V
  2. Measure the AC voltage between the YELLOW wires. = 0V
  3. Measure the AC voltage between the GREEN wires. = 0V
 
Can you take a look at the transformer input side voltages?
From BLU to YEL should be 120V and from ORG to BRN should be 120V.
Careful, these are directly connected to the AC line voltage input.
 
Thanks for questioning what I did. I am confused, unless I am missing something, because how can I get probe onto the wire that is inside the transformer. I made the test by the wires from the the three fuses.
Ok, I think I understand now. There are two orange wires coming out of the transformer and you want me to probe the other ends and tell you the voltage. OK. Im on it.
 
Please confirm what I am looking at is correct. I followed the two heavy orange wires from the transformer to the other ends which I circled in my attached diagram. Is this one of the one location you want me to measure?
 

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Jomo1960 said:
Please confirm what I am looking at is correct. I followed the two heavy orange wires from the transformer to the other ends which I circled in my attached diagram. Is this one of the one location you want me to measure?
Click to expand...
OK, I see that you gave me the thumbs up. The ACV across those two orange terminals is 0v
 
I see the two yellow wires coming out of the transformer but they go to the other side of the circuit board and on the other side of the circuit board there is a cover there and I can't trace the two yellow wires.
 
The two yellow wires should go to one side of fuse FR03 and the other to fuse FR01.
The two green wires should go to one side of fuse FR01 and the other side to chassis ground.
The two orange wires go to the bridge rectifier as you show in your photo.
See if you get any voltage on the YEL and GRN wires. If not we need to check the input to the transformer.


1790440629777.png
 
I am confused as I gave you the voltages three times for the wires that have the fuse between them. Is that what you want? All those voltages are 0VAC.
 
I'm sorry, but I don't recall you providing those voltages to me three times. I looked back at your previous posts and did not see any voltages to the fuse inputs provided by you. I see where you checked continuity. Please tell me the Post #'s and I will review your comments and data.
 
Last edited:
It doesn't matter that you asked me a few times. I am just reminding you so we can move ahead. The voltages across the fuses were mention in posts 6-7 and 41-42 and then again in post 50.
All that matters is that in the end I/we figure out what the problem is. I truly appreciate your help. I am trying my very best to follow your instruction to make things easier for you.
 
Jomo1960 said:
The voltages across the fuses were mention in posts 6-7 and 41-42 and then again in post 50.
Click to expand...
Just to clarify what I am asking, I don't want the voltages ACROSS THE FUSES, I am asking about the voltage between wires going to the fuses from the transformer. See diagram below.
Post #50 is my post not yours.​
Post #6 is my post where you did not do as I asked. Post #7 is where you measured from each fuse to GND... not from transformer lead to lead. Also, you did not say you measured ACV or DCV.​
Post #41 is my post. #42 is saying that you got 0v same as before, but if you are referring to post #6 it is not what I asked.​

OK, because you say that you can't trace the yellow and green wires, you can measure them at the fuse board.
Please measure the ACV from YEL arrow to YEL arrow.
Please measure the ACV from GRN arrow to chassis GND.
I don't think you did this before, but if you did please

If you get 0V for all three sets of wires, then you either have a problem on the primary side of the transformer or a bad transformer, but it takes so long to get answers from you that it will take another 5 days to get what we need to determine if it is really bad.

1790445656721.png
 
Thank you.
Last check...
  • On the transformer input side measure the ACV from the BLU wire to the GRN wire, then from the BLU wire to the YEL wire.
  • Next, again on the input side measure the ACV from the ORG wire to the BRN wire, then from the ORG wire to the RED wire.
  • These wires will go to the back side of the voltage selection socket.
1790447271416.png
 
It looks like the voltage is not getting through the voltage selector to the transformer, but it's hard to tell because I can't figure out the wiring.
Can you look for pin numbers on the voltage selector socket. I don't know if it is on the front side or back side.
  • From the schematic, one side of the AC input goes to Pin 1 (and Pin 2), blue highlight and the other side, green highlight goes to Pin 7 (and Pin 8) on the voltage selector.
  • With power OFF and UNPLUGGED, set your DMM to measure Ohms and connect it to one side of the plug.
  • Connect the other DMM probe to each pin on the socket until you find a connection (0 Ohms).
  • There should be two of them. That would be either 1/2 or 7/8.
  • Do the same for the other contact on the AC plug.
  • Make note of which side of the plug connects to which pin(s).
  • Next, (Be Careful) plug the AC cord back into the outlet and push in the power switch. Measure the ACV between Pin 1(2) and Pin 7(8).
  • You should read line voltage of 120VAC.
1790448830876.png
 
Here is a summary of the voltages that you measured.
From what I can see, the 120VAC is not getting to the voltage selector socket. because all of the transformer primaries you measured are 0V.
Can you measure from pin 1 or 2 on the socket (BRN wire) to pin 7 or 8 on the socket. You should have 120VAC.
1790486883615.png
The photo of the voltage selector plug you posted has 4 pins.
Can you tell me which pins on this voltage selector plug are connected to which pins?
1790487203691.png
 
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