I'm swapping a G07 with minor burn into a Gyruss, replacing the K4900 that was there...
I recapped the chassis and neck board (caps only), tested it in the original horizontal mount - looked beautiful. Swapped tube and chassis into vertical frame and retested out of the cabinet - looked beautiful. Noticed that the degaussing coil was not grounded to the chassis, so i grounded it but did not test. All tests were done plugging into the cabinet wiring (with isolation xformer).
Inserted into cabinet, connected the ground wires (speakers and cabinet) to the bolt attaching monitor frame to the cabinet, as original. Powered on and didn't get video - F902 is blown.
Removed from cabinet, plugged in a different G07 (had been capped, but not tested). This time I removed the degaussing coil ground from frame and taped it. I think i still had the 2 leads to the degausing coil plugged into the chassis. F902 blew immediately.
Fromm's flowchart says to check diodes 901-904, and all test ok.
where do i go from here? do i replace 902 and try again without the degauss coil? Did i do something to my tube/yoke?
thanks for any info.
John
I recapped the chassis and neck board (caps only), tested it in the original horizontal mount - looked beautiful. Swapped tube and chassis into vertical frame and retested out of the cabinet - looked beautiful. Noticed that the degaussing coil was not grounded to the chassis, so i grounded it but did not test. All tests were done plugging into the cabinet wiring (with isolation xformer).
Inserted into cabinet, connected the ground wires (speakers and cabinet) to the bolt attaching monitor frame to the cabinet, as original. Powered on and didn't get video - F902 is blown.
Removed from cabinet, plugged in a different G07 (had been capped, but not tested). This time I removed the degaussing coil ground from frame and taped it. I think i still had the 2 leads to the degausing coil plugged into the chassis. F902 blew immediately.
Fromm's flowchart says to check diodes 901-904, and all test ok.
where do i go from here? do i replace 902 and try again without the degauss coil? Did i do something to my tube/yoke?
thanks for any info.
John
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