221/Repairs: Difference between revisions
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(Created page with "The 221 has a switching power supply. It has a transformer couple trigger circuit which produces a Dc level base trigger.It gets fried when the batter gets so old they draw t...") |
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=Common Problems= | |||
==Failing PSU== | |||
The 221 has a switching power supply. It has | The 221 has a switching power supply. It has | ||
a transformer | a transformer coupled trigger circuit which produces | ||
a | a DC level base trigger. It gets fried when the battery | ||
gets | 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 11:28, 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