Hi! Over the years I have several times removed and rebuilt the lamp oven cylinders for the HP5065A optical unit. This is a time consuming and tricky bit of work as the other wiring runs just under the surface of the potting used to hold the cylinder. Knowing where they approximately lie and being careful not to remove the potting in a large area around that point (I call it the exclusion zone!) the cylinder can be removed. I just had the occasion to rebuild an optical unit that had lost continuity to BOTH ovens AND the C-field winding! A bit daunting but after quite a bit of work success! It easily meets specs and is working quite well. Thought I'd share a PIX of the innards prior to the rebuild. Cheers, Corby

Corby Helpful pix. Did they all fail indepently or was there some sort of failure that caused the failure. I would certainly like to know how you may have rewound the heaters. How about the exclusion area? Regards Paul WB8TSL On Mon, Jun 13, 2022 at 12:22 PM Corby Dawson via time-nuts < time-nuts@lists.febo.com> wrote: > Hi! > > Over the years I have several times removed and rebuilt the lamp oven > cylinders for the HP5065A optical unit. > This is a time consuming and tricky bit of work as the other wiring runs > just under the surface of the potting used to hold the cylinder. Knowing > where they approximately lie and being careful not to remove the potting > in a large area around that point (I call it the exclusion zone!) the > cylinder can be removed. > > I just had the occasion to rebuild an optical unit that had lost > continuity to BOTH ovens AND the C-field winding! > > A bit daunting but after quite a bit of work success! It easily meets > specs and is working quite well. > Thought I'd share a PIX of the innards prior to the rebuild. > > Cheers, > > Corby_______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com