Is the secondary of this R core transformer in the picture wired correctly? The legend on the transformer indicates both blue are 12 volts and both brown are 12 volts. This is wired to an LDR attenuator. Or am I not reading that correctly?
Thanks
Thanks
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The blue wires are the two ends of one winding, and the brown wires are the two ends of another winding.
I think that the two blues should be in one of the connectors, and the two browns should be in the other connector.
But it would help if you have the actual schematic of the equipment.
I think that the two blues should be in one of the connectors, and the two browns should be in the other connector.
But it would help if you have the actual schematic of the equipment.
Yes, think that's ok. Blues to one connector, browns to the other connector.
Seems to be a half wave rectified, dual polarity supply.
Seems to be a half wave rectified, dual polarity supply.
Check with a meter in minimum ohms range, short the leads to check the actual zero of the meter.
Some meters don't show zero when the leads are shorted, and subtract that reading from the measured readings.
That will give you some idea of what is going on.
Some meters don't show zero when the leads are shorted, and subtract that reading from the measured readings.
That will give you some idea of what is going on.
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Ok, checking again, the transformer windings are different than above. There is one secondary winding
with blue/brown leads, and also another secondary winding with blue/brown leads.
So you must use an ohm meter to pair the leads for each winding. Find two of the leads that measure a few ohms
(not open circuit), and that's one secondary winding. Then the other pair of leads is the other winding.
Then we have to determine how the windings are connected, which is a completely separate issue.
This power supply is different than the usual one, so take a photo of the bottom of the board.
with blue/brown leads, and also another secondary winding with blue/brown leads.
So you must use an ohm meter to pair the leads for each winding. Find two of the leads that measure a few ohms
(not open circuit), and that's one secondary winding. Then the other pair of leads is the other winding.
Then we have to determine how the windings are connected, which is a completely separate issue.
This power supply is different than the usual one, so take a photo of the bottom of the board.
Center blue and green look joined in the schematic...I may be wrong.
Meter will show short if that is the case.
Meter will show short if that is the case.
Why?
Unit is not with you?
Should be easy enough to disconnect and turn upside down...and take a photo.
Unit is not with you?
Should be easy enough to disconnect and turn upside down...and take a photo.
Here’s a couple pictures:
I’m also wondering what if any difference the R core might make?
The note on the pcb says “toroid only “
Thanks
I’m also wondering what if any difference the R core might make?
The note on the pcb says “toroid only “
Thanks
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R core will work just fine. Your R core winding has two secondary windings instead of what is shown, a center tapped single winding. You can check the windings with an ohmeter as stated above. I have the exact same transformer and the blue leads are one winding, the brown leads are the second winding.
Thanks everyone,
I pulled the lighter note ldr and have gone back to my tube preamp. I’m fairly certain something is not right about the lighter note but for now will not be to concerned. Does seem odd that the balance pot has no discernible affect.
If anyone else has any insight please let me know.
thanks again
I pulled the lighter note ldr and have gone back to my tube preamp. I’m fairly certain something is not right about the lighter note but for now will not be to concerned. Does seem odd that the balance pot has no discernible affect.
If anyone else has any insight please let me know.
thanks again