09-06-2026, 10:32 AM
At the Broadcast Engineering Museum we have far too many duff scopes and not enough good ones. In the Central Apparatus Room we have a Tek 2465 which is a very fine 300MHz instrument except channel 2 is duff. Almost certainly the hybrid. I think we have a donor scope.
There was a Tek 2225 (a good and useful scope though not in the league of the 2465) which had a label "Trips RCD a few minutes after switch on". Looked up the manual (we may have a paper copy but the Tek wiki is easier than checking in our library) and found that there's a toroidal mains transformer feeding about 60V to various switchmode regulators. An odd sort of hybrid design. Changed all three RIFA caps and it ran for several hours on soak test.
There was a Tek 2225 (a good and useful scope though not in the league of the 2465) which had a label "Trips RCD a few minutes after switch on". Looked up the manual (we may have a paper copy but the Tek wiki is easier than checking in our library) and found that there's a toroidal mains transformer feeding about 60V to various switchmode regulators. An odd sort of hybrid design. Changed all three RIFA caps and it ran for several hours on soak test.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
