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RogerEvans · 17th Mar 2020, 6:23 pm

I would like to try and help on this but I am struggling with the online scanned manuals which seem a bit garbled in the schematics of the sweep circuitry. There is a high quality scan available online from Artek manuals in the US (artekmanuals.com), make sure you order the 465 or 465B as appropriate.

You could try asking on TekScopes (groups.io/g/TekScopes), there are several people there with 465s and many old threads on 465 repairs. I have two 454s and a 475, all of which have socketed transistors in the sweep circuitry. All three have at some time required attention to sweep and triggering problems and all three were solved simply by pulling transistors and testing them on one of the cheap Chinese component testers. I also keep a small supply of 2N3904 and 2N3906 so that I can swap in a PNP or NPN as appropriate and this is nearly always good enough to prove that the circuitry then works at moderate sweep speeds.

The bad news is that I had a 7000 series timebase that would not sweep and the fault there was a failed U870 (part no 155-0049-01). They are available but are not cheap.

Best of luck,

Roger

17th Mar 2020, 6:23 pm	#7
RogerEvans Hexode Join Date: Oct 2014 Location: Wiltshire, UK. Posts: 382	Re: Tektronix 465 not sweeping I would like to try and help on this but I am struggling with the online scanned manuals which seem a bit garbled in the schematics of the sweep circuitry. There is a high quality scan available online from Artek manuals in the US (artekmanuals.com), make sure you order the 465 or 465B as appropriate. You could try asking on TekScopes (groups.io/g/TekScopes), there are several people there with 465s and many old threads on 465 repairs. I have two 454s and a 475, all of which have socketed transistors in the sweep circuitry. All three have at some time required attention to sweep and triggering problems and all three were solved simply by pulling transistors and testing them on one of the cheap Chinese component testers. I also keep a small supply of 2N3904 and 2N3906 so that I can swap in a PNP or NPN as appropriate and this is nearly always good enough to prove that the circuitry then works at moderate sweep speeds. The bad news is that I had a 7000 series timebase that would not sweep and the fault there was a failed U870 (part no 155-0049-01). They are available but are not cheap. Best of luck, Roger