221/Repairs: Difference between revisions
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=Common Problems= | |||
( | ==Failing PSU== | ||
The 221 has a switching power supply. It has | |||
a transformer coupled trigger circuit which produces | |||
a DC level base trigger. It gets fried when the battery | |||
gets old and draws too much current.<br> | |||
<br> | |||
More often than not, the T633 Transformer (part number [[120-0876-00]]) | |||
is the thing to fail.<br> | |||
==Failed capacitors== | |||
[https://www.youtube.com/@justanotherelectronicsblog5490/videos justanotherelectronicsblog@YouTube] found C714 short when [https://www.youtube.com/watch?v=bZ6agALKXjs fixing his 221] | |||
[[Category:Instrument repair reports]] | |||
Latest revision as of 10:28, 19 October 2023
Common Problems
Failing PSU
The 221 has a switching power supply. It has
a transformer coupled trigger circuit which produces
a DC level base trigger. It gets fried when the battery
gets old and draws too much current.
More often than not, the T633 Transformer (part number 120-0876-00)
is the thing to fail.
Failed capacitors
justanotherelectronicsblog@YouTube found C714 short when fixing his 221