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I am an experienced electronics repair person, but a newbie when it comes to tube amp repair.
I was given a non-working Silverton 1482 amplifier. I plugged it in and the power light came on, but about 1 minute later the power transformer starting smoking out the holes where the wires come out, so I am pretty sure it is bad.
The heaters in the tubes did not come on either. The unit did not blow a fuse.
I want to replace the transformer, and it doesn't have to be cosmetically correct, but I would like it to be electrically sufficient.
Here is the info I have gleaned:
There are no numbers on the transformer.
Primary is two wires, and it is for 115V.
The secondary after the rectifier tube (Tube type 6X4) is supposed to be 350V, and the output stages on this amp are two 6V6GT tubes. The heater secondary output is 6.3VAC.
The wattage of the amplifier is 15W, and the primary input power rating is 70W total at 115V.
The speaker is 4 Ohms running on a 4 ohm tap on the output transformer.
There are two secondary’s, one is center tapped three wire for the main power at 350V DC, and the other is two wire at 6.3VAC.
Since the primary is rated at 70W, I assume it will have maximum 70/115-> .61A in it. The fuse is 1 slow blo 1A MDL, which also validates the .61A number.
Would anyone on this board be able to advise me on a specific transformer (or pair of transformers) that might work, and where to get them?
What should the voltage rating of the secondary be in order to crated 350V DC? Is this calculated similarly if you just had had two diodes feeding the caps, or is there more drop in the tube rectifier than in a silicon diode?
I also need to know the amperage rating of the two secondary windings, as this info isn't in the schematic.
The schematic is here for reference: http://www.silvertoneworld.net/schem...rtone_1482.pdf
Thanks in advance for any help.
GregGarner
I was given a non-working Silverton 1482 amplifier. I plugged it in and the power light came on, but about 1 minute later the power transformer starting smoking out the holes where the wires come out, so I am pretty sure it is bad.
The heaters in the tubes did not come on either. The unit did not blow a fuse.
I want to replace the transformer, and it doesn't have to be cosmetically correct, but I would like it to be electrically sufficient.
Here is the info I have gleaned:
There are no numbers on the transformer.
Primary is two wires, and it is for 115V.
The secondary after the rectifier tube (Tube type 6X4) is supposed to be 350V, and the output stages on this amp are two 6V6GT tubes. The heater secondary output is 6.3VAC.
The wattage of the amplifier is 15W, and the primary input power rating is 70W total at 115V.
The speaker is 4 Ohms running on a 4 ohm tap on the output transformer.
There are two secondary’s, one is center tapped three wire for the main power at 350V DC, and the other is two wire at 6.3VAC.
Since the primary is rated at 70W, I assume it will have maximum 70/115-> .61A in it. The fuse is 1 slow blo 1A MDL, which also validates the .61A number.
Would anyone on this board be able to advise me on a specific transformer (or pair of transformers) that might work, and where to get them?
What should the voltage rating of the secondary be in order to crated 350V DC? Is this calculated similarly if you just had had two diodes feeding the caps, or is there more drop in the tube rectifier than in a silicon diode?
I also need to know the amperage rating of the two secondary windings, as this info isn't in the schematic.
The schematic is here for reference: http://www.silvertoneworld.net/schem...rtone_1482.pdf
Thanks in advance for any help.
GregGarner
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