If it does not work at all, the power supply is bad.
The power supply is simple. You should have HIGH VOLTAGE A.C. on one side of the rectifier tube, HIGH VOLTAGE D.C. on the other side. Figure out which tube is the rectifier (it might not have a tube rectifier) and look-up the pin connections. And be careful.
The power supply is simple. You should have HIGH VOLTAGE A.C. on one side of the rectifier tube, HIGH VOLTAGE D.C. on the other side. Figure out which tube is the rectifier (it might not have a tube rectifier) and look-up the pin connections. And be careful.
Hi !
Yes tubes may be bad .. or may be not !
Testing tubes outside your amp means using a tube tester, and if you have not, it's simpler to check voltages against the schematic.
Here is what I've found about Sansui AU111:
http://www.bonavolta.ch/hobby/fr/audio/sansui.htm
If this can help ....
Does the tube glows ?
If not, what is voltage at pins 4, 5 and 9 ?
What is the voltage at the tube's anode ?
... just to start ...
Yves.
Yes tubes may be bad .. or may be not !
Testing tubes outside your amp means using a tube tester, and if you have not, it's simpler to check voltages against the schematic.
Here is what I've found about Sansui AU111:
http://www.bonavolta.ch/hobby/fr/audio/sansui.htm
If this can help ....
Does the tube glows ?
If not, what is voltage at pins 4, 5 and 9 ?
What is the voltage at the tube's anode ?
... just to start ...
Yves.
Thank you yves
In fact I am french from Paris .
I will check the output once I change the resistor and others in order to start .
In fact I have the schematic for the amp!
Just wanted to know if there is a way to test tube without havig a tube tester ? continuity or something like .
Regards
Gerard
In fact I am french from Paris .
I will check the output once I change the resistor and others in order to start .
In fact I have the schematic for the amp!
Just wanted to know if there is a way to test tube without havig a tube tester ? continuity or something like .
Regards
Gerard
Same subject:
The question have been asked earlier, but I could not find a clear answer:
Are there any method to test a tube without a tube tester, any of the parameters?
I am bussy repairing an old stereo Sansui radio/amp combo, using ECL82 tubes. The 1 old set of tubes I got , work well on both channels. I bought another set, which turned bright orange after 3 minutes. Took back to tube guy and exchanged for another "new" set. Now I notice a blue glow between the plates of both new tubes. All voltages compares correct to the service manual.
Any suggestions on this problem and tube testing?
The question have been asked earlier, but I could not find a clear answer:
Are there any method to test a tube without a tube tester, any of the parameters?
I am bussy repairing an old stereo Sansui radio/amp combo, using ECL82 tubes. The 1 old set of tubes I got , work well on both channels. I bought another set, which turned bright orange after 3 minutes. Took back to tube guy and exchanged for another "new" set. Now I notice a blue glow between the plates of both new tubes. All voltages compares correct to the service manual.
Any suggestions on this problem and tube testing?
the new set turned bright orange because everytime you replace tubes u must bios the amp. blue glow is fine gassy tubes or new tubes do that.
if you wana test tubes get a tube tester. just one of manny
http://cgi.ebay.ca/LAFAYETTE-TE-55-...537705212QQcategoryZ25422QQrdZ1QQcmdZViewItem
if you wana test tubes get a tube tester. just one of manny
http://cgi.ebay.ca/LAFAYETTE-TE-55-...537705212QQcategoryZ25422QQrdZ1QQcmdZViewItem
Normal failure in a tube creates lower to no current flow. Odd times elements may short, but the plate will have burn or "cook" marks on it. The best way to check a tube is in circuit and measure the terminal voltages.
Other parts will get you more often. Coupling caps are prime here. Run the unit up with no tubes (except rectifier) to about 70% ac voltage. The grids should measure 0V. Some power tubes are biased with a negative voltage. Some regulators "float" at some positive voltage.
With negative supplies for outputs, look at the ripple. There should be none.
-Chris
Other parts will get you more often. Coupling caps are prime here. Run the unit up with no tubes (except rectifier) to about 70% ac voltage. The grids should measure 0V. Some power tubes are biased with a negative voltage. Some regulators "float" at some positive voltage.
With negative supplies for outputs, look at the ripple. There should be none.
-Chris
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