This is not my first amp but frst time using this tranformer.
Both heater secondaries are funtioning fine with centertap grounded.
No tubes or caps are connected.
high voltage secondaries (red wires) are disconected from amp
I am using a full wave rectifer on the high voltage secondaries.
the centertap (yellow wires) can be grounded, and the rectifier can be grounded, but not at the same time.
If I do it shorts and the PT hums and shakes like crazy.
when just the rectifier is grounded the voltage drops to 286 from 340 (measuring one side)
I have swapped the diodes with new ones but no change.
measuring the voltage through just the diode measures 340 cathode and 178 anode
Diode is rated for 1kv
two types used 1N5408 and BYv26E
I hope someone has an idead of what migh be going on.
Both heater secondaries are funtioning fine with centertap grounded.
No tubes or caps are connected.
high voltage secondaries (red wires) are disconected from amp
I am using a full wave rectifer on the high voltage secondaries.
the centertap (yellow wires) can be grounded, and the rectifier can be grounded, but not at the same time.
If I do it shorts and the PT hums and shakes like crazy.
when just the rectifier is grounded the voltage drops to 286 from 340 (measuring one side)
I have swapped the diodes with new ones but no change.
measuring the voltage through just the diode measures 340 cathode and 178 anode
Diode is rated for 1kv
two types used 1N5408 and BYv26E
I hope someone has an idead of what migh be going on.
We would need to see a schematic of how you hooked up the diodes because your description is not clear.
there is literally nothing connected to the PT high voltage secondaries at this ponit.
Just testing the rectifier.
But I think I figured it out.
The full wave rctifier circuit I posted above creates a similated center tap for PTs that dont have one.
Since I do have one on my PT, it does not want both grounded
Just testing the rectifier.
But I think I figured it out.
The full wave rctifier circuit I posted above creates a similated center tap for PTs that dont have one.
Since I do have one on my PT, it does not want both grounded
A full wave bridge rectifier does not use a center tap. One output may be grounded, to create a unipolar supply.
If you use a secondary with a center tap, only two diodes are needed per output polarity if the CT is grounded.
If you use four diodes, that gives both a positive and a negative output, relative to the center tap which is grounded.
Neither of the two outputs can then be grounded.
If you use a secondary with a center tap, only two diodes are needed per output polarity if the CT is grounded.
If you use four diodes, that gives both a positive and a negative output, relative to the center tap which is grounded.
Neither of the two outputs can then be grounded.
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Also note that 1KV diodes are marginal for 343VAC since 343 * 2.828 = 970VDC.
Yes, but silicon diodes like that have a substantial peak-surge rating as well as a peak current rating.
I removed the two un-needed diodes and just have the center tap grounded and it all looks good.
this transormer is working as planned using the extra 6v heater secondaries to power the 5vdc regulator for the relays and PIC controler
this transormer is working as planned using the extra 6v heater secondaries to power the 5vdc regulator for the relays and PIC controler
You have to understand electical "travel" through diodes, etc.
There are bridge diode arrays (which you showed shorting out).
And there are "full wave" arrays (two diodes - success).
Because the problems you had are the result of not learning the fundamentals of electronics - obvious you skipped that and jumped right in to avoid the boring teachings as do many others.
