01-25-2016, 06:45 PM
I bought this head, VT 120, back in the 90's for $50..it had and has a couple of problems..I'll start with the weird one...I turned it on the other day and it blew the 5 amp fuse...I put it on the bench and removed all tubes...and started eliminating each circuit one at at time checking for shorts..then started installing tubes one at a time.....after every thing was back together..the short was gone....
Here it is..Brown wire of the transformer feeds pin 3 of two of your output tubes.....The blue wire from the trans..feeds pin 3 of the other two tubes...These two circuits do not connect together according to the schematic..
how ever there is a piece of land that runs to the back of the board and ends at a slot cut in the board...this point may be familiar to some people..and if a jumper was placed there , it would connect the two circuits...there is no jumper however, the land at that point has been burned and lifted..?????? as though something was there at one time.
what is this?? its crazy... what was there that burned if the schematic shows these are not connected?? unless the schematic I have is for a different vt 120 head..
..Here is the other problem...before this happened, the amp ran fine for a week or two , but all of a sudden the volumn would fade out...I cleaned all pots...but it continued the problem..anyone might know why volumn could fade out intermitantly
Here it is..Brown wire of the transformer feeds pin 3 of two of your output tubes.....The blue wire from the trans..feeds pin 3 of the other two tubes...These two circuits do not connect together according to the schematic..
how ever there is a piece of land that runs to the back of the board and ends at a slot cut in the board...this point may be familiar to some people..and if a jumper was placed there , it would connect the two circuits...there is no jumper however, the land at that point has been burned and lifted..?????? as though something was there at one time.
what is this?? its crazy... what was there that burned if the schematic shows these are not connected?? unless the schematic I have is for a different vt 120 head..
..Here is the other problem...before this happened, the amp ran fine for a week or two , but all of a sudden the volumn would fade out...I cleaned all pots...but it continued the problem..anyone might know why volumn could fade out intermitantly
