Re: Tek 465B Diagnosis Comments Requested #photo-notice


 

It sounds like the attenuator blocks have dirty contact pins. The solution to this is to clean the pins of the attenuator blocks with a cotton swab and isopropyl alcohol. The procedure is fairly simply: one at a time, remove each attenuator block, clean it's pins with the swab dipped in anhydrous pure isopropyl alcohol, and reinstall the block. You should only remove one block at a time so that you don't get confused about which block goes in which socket. This is a known problem with the 465 and 475 scopes. It also happens to the socketed transistors and ICs elsewhere in the instrument, and those can be fixed by the same procedure.

The attenuator board does not need to be removed. You can unseat each attenuator block from the top using the same access you currently use to "press down" on each block. You can gently rock the block back and forth lengthwise to unseat it from its socket. You might want to use a small tool to gently lever the block out of its socket incrementally from alternate ends.

-- Jeff Dutky

Join TekScopes@groups.io to automatically receive all group messages.