Just for some closure on the cause of this problem. I pulled the U225 Hybrid off the board and carefully took the plastic cover off the top of the board. Looking at this under the microscope, you

I think Brad was on the right track suggesting thermal shock to the tubes from getting wet. I'd go a step further and say this may have been in a flood or other watery event, while operating! It

Bill -With respect to brightness vs high voltage, I also had a 2215 with a relatively dim trace.  Having an old flyback transformer, I made up a RF power supply with voltage multipliers driven by an

Hello Brad, You made my day with that comment about the TV set! Back when I was 12 or 13 years old, my father picked up a Tektronix 545B of the side of the road for me. I think it was kept in a barn

If it's a medium to high power four-leaded RF transistor, it will be in a stripline type package, and the emitter is usually connected to two of the opposing leads. If it's in a can like TO-72, with

Brenda via groups.io wrote on 4/30/2020 2:44 PM: Hello, Brenda-- Whew... the wiring side is in better condition than I expected. Check any small inductors for opens-- there's one located in the

Hello Brad, None of the tubes seem to have been pulled, other than the 6AX5 and the crystal oven. No broken tips or bases until I started to try to pull them out. But I have added a pic on Imgur of

Well, I do know that this unit came from Alabama and probably was from a vacant property or was left in a barn. Either way, I have never seen so much corrosion, which may well be from salt as well. As

Brenda via groups.io wrote on 4/30/2020 2:02 PM: Hello, Brenda-- If the seller advertised this 181 as being in working condition, you might want to file a claim with eBay for false advertising. I'll

I'm guessing it was kept out doors (unheated barn?) and the summer/winter thermal cycles finally got to the tubes... Are the tips broken off, glass cracked, or is it the glass/metal seals at the pins

The switch frame looks like corrosion from a humid environment, along with the usual dust and grime.  I came across a bunch of Tek 5xx scopes and plugins a few years ago (SF bay area) that had been

Hello everyone, I have purchased a Tektronix 181 Time-Mark Generator from the evil eBay site. I thought that this would be in decent shape and boy was I wrong!! There are 7 tubes out of 19 tubes that

I havent a clue Dave manuals@... -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Dennis left the group wide open, so whatever your settings for emails was before, it still is. I had to login to yahoo, goto the manage my groups tab, and then set all of my groups to no emails. I

Hi all, I wonder what type of transistor SG503 Q190 (151-0614-00) is. Just curiosity. Q190 is 4-lead: B, C, E1, E2. In doing measurements to help Michael Lynch I found about 0.7 V difference between

Dave, Don’t know what happened here but after your sending a message to the old Tekscopes Yah group I started to receive individual reply messages from that site for “496 looses the magic

Oh, so you noticed the mess that is the best manual... Tektronix wasn't exactly very good at making manuals. They Did huge prints on the manual they had on hand when the instrument was first

Thank you! The "you" was indeed Chuck Harris. I apologize for any misunderstanding. I don't know how to (in green) "Show quoted text"; it seems a waste of space to show the actual quote. I am

Back when the 2215 was made there was a novel, pcb mounted, piezoelectric fan that was being debuted. It had a thin wing that vibrated back in forth in time to an oscillator driven piezoelectric

I sent the time below to the old yahoo group ,  gotta clean out my Address book..Surprised it still works Dave ArtekManuals Yesterday I dug my trusty 496 out of retirement to check it out before I