Pulled the trigger on a brand new 344654A, should be here around new years hopefully, pretty excited.
Got it for the $16xx price, within hours of the purchase Newark revised the price up to $25xx. I guess that is the inflation observed in real time, still, it made me feel better about a big ticket purchase I was having some anxiety about.
You are a bastard (if you don't post a pic of the new puppy when it arrives)!
IMHO Newark prices are always so high for no reasons.
Pulled the trigger on a brand new 344654A, should be here around new years hopefully, pretty excited.
Got it for the $16xx price, within hours of the purchase Newark revised the price up to $25xx. I guess that is the inflation observed in real time, still, it made me feel better about a big ticket purchase I was having some anxiety about.
You are a bastard (if you don't post a pic of the new puppy when it arrives)!
IMHO Newark prices are always so high for no reasons.
the price was the same at Mouser and on Keysight's website, down to the penny, pretty sure it was the MSRP at the time.
in my previous post.
It was a 12AT7 tube, V474 on the upper beam sub-assembly. Looked it up in the schematics, it's the tube that drive the lower deflection plate. Tek scopes seldom use the 12AT7, have very few of them... ended up pulling one from my other 502A (which I know works). Need to buy a new tube now then, of course. Hopefulyl they are cheap and I can buy two or 3 of them to have spares.

It was a 12AT7 tube, V474 on the upper beam sub-assembly. Looked it up in the schematics, it's the tube that drive the lower deflection plate. Tek scopes seldom use the 12AT7, have very few of them... ended up pulling one from my other 502A (which I know works). Need to buy a new tube now then, of course. Hopefulyl they are cheap and I can buy two or 3 of them to have spares.
In our part of the world it's ECC81, and it is common in guitar amps. Still being made. Expect to pay about 15€ for it. Or 45€ if you are a man0 with small genitals, a very unscientific stereo system, and want NOS.
Footnote 0: I could be modern and say "person", but since the people who "want to believe" are overwhelmingly self-identifying as cis men I will not. Any female audiophool who feels left out: Sorry, not sorry. You should know better; because this shit is where cis men lose themselves. Don't get dragged down to their level.
The one under the small scope in the background: Powersupply?
More likely some sort of very accurate frequency generator?
It was a 12AT7 tube, V474 on the upper beam sub-assembly. Looked it up in the schematics, it's the tube that drive the lower deflection plate. Tek scopes seldom use the 12AT7, have very few of them... ended up pulling one from my other 502A (which I know works). Need to buy a new tube now then, of course. Hopefulyl they are cheap and I can buy two or 3 of them to have spares.
In our part of the world it's ECC81, and it is common in guitar amps. Still being made. Expect to pay about 15€ for it. Or 45€ if you are a man0 with small genitals, a very unscientific stereo system, and want NOS.
It was a 12AT7 tube, V474 on the upper beam sub-assembly. Looked it up in the schematics, it's the tube that drive the lower deflection plate. Tek scopes seldom use the 12AT7, have very few of them... ended up pulling one from my other 502A (which I know works). Need to buy a new tube now then, of course. Hopefulyl they are cheap and I can buy two or 3 of them to have spares.
In our part of the world it's ECC81, and it is common in guitar amps. Still being made. Expect to pay about 15€ for it. Or 45€ if you are a man0 with small genitals, a very unscientific stereo system, and want NOS.
Footnote 0: I could be modern and say "person", but since the people who "want to believe" are overwhelmingly self-identifying as cis men I will not. Any female audiophool who feels left out: Sorry, not sorry. You should know better; because this shit is where cis men lose themselves. Don't get dragged down to their level.
12AT7, 12AU7, 12AX7, etc are as common as dirt over here. And cheap as dirt too as long as you stick with RCA or GE. But if you want the "ECC" version of these tubes which are far superior and sound better (Yea, right) then audiophool pricing takes effect.


It was a 12AT7 tube, V474 on the upper beam sub-assembly. Looked it up in the schematics, it's the tube that drive the lower deflection plate. Tek scopes seldom use the 12AT7, have very few of them... ended up pulling one from my other 502A (which I know works). Need to buy a new tube now then, of course. Hopefulyl they are cheap and I can buy two or 3 of them to have spares.
In our part of the world it's ECC81, and it is common in guitar amps. Still being made. Expect to pay about 15€ for it. Or 45€ if you are a man0 with small genitals, a very unscientific stereo system, and want NOS.
Footnote 0: I could be modern and say "person", but since the people who "want to believe" are overwhelmingly self-identifying as cis men I will not. Any female audiophool who feels left out: Sorry, not sorry. You should know better; because this shit is where cis men lose themselves. Don't get dragged down to their level.
12AT7, 12AU7, 12AX7, etc are as common as dirt over here. And cheap as dirt too as long as you stick with RCA or GE. But if you want the "ECC" version of these tubes which are far superior and sound better (Yea, right) then audiophool pricing takes effect.
If they are so cheap send me a dozen of them so I have some stock here !
ECC is just the European designation for the 12A-X/Y/Z , it's the same tube as Mansaxel said. Hell even that audiophool website I mentioned, is honest enough to admit it upfront ! They do say though, indeed, that the audio guys often are hesitant to buy the tube under its ECC / European designation, thinking it would sound different (worse) somehow !
https://humbuckersoup.com/ecc83-vs-12ax7-tubes-difference/
Found som article-blabla about watches. But the photos are end of the 1960's and the 5th one is from the labor with the 2 men who made the work and the one who earns the money. Beside of that there are some nice instruments:
i see at least 2 scopes which i think i recognise and som other gear. Who knows what it is? The one under the small scope in the background: Powersupply?
https://de-watchpro-com.translate.goog/vor-50-jahren-gewann-junghans-das-rennen-um-die-erste-deutsche-quarzuhr/?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=de
only the picture:
OK so here is the 502A !
....snip
Found som article-blabla about watches. But the photos are end of the 1960's and the 5th one is from the labor with the 2 men who made the work and the one who earns the money. Beside of that there are some nice instruments:
i see at least 2 scopes which i think i recognise and som other gear. Who knows what it is? The one under the small scope in the background: Powersupply?
https://de-watchpro-com.translate.goog/vor-50-jahren-gewann-junghans-das-rennen-um-die-erste-deutsche-quarzuhr/?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=de
only the picture:
That guy in the suit was in the movie Goodfellas. I swear! https://www.thekitchn.com/the-celluloid-p-5-6591
My question is why do they look so freaking happy?![]()
What do you mean? They're Germans. That's how we look when we're really happy & excited.





OK so here is the 502A !
....snip
Vince, good score!And while it does look like it spent some time in a damp environment it should clean up rather well. And don't worry about the HV transformer. Yours is potted in wax and not prone to absorb moisture like the Type 547's where it's potted in epoxy with the result I'm fighting now.
The handles. Yep, those old leather handles rot and fall apart. Luckily Tek later went to much more durable plastic handles. I had the same issue with my Type 535A. Nothing left but the rusty inner frame. I bought some leather strips and a leather tool kit and made new ones utilizing that inner frame. It came out decent and secure enough to be able to easily lift the scope.![]()
And there's an alternative. The single handle on a Type 561B was too far gone. So I took it off and used this handle instead. This does involve drilling the top plate and also notching the covers so they fit. But it works perfectly. If you were to do this on the Type 502A you would need 2 of them.

More likely some sort of very accurate frequency generator?
Most probably something by Schomandl (the eternal Frequenzdekade comes to mind) or Wandel & Goltermann.
Mother Nature left a reminder note last night.

OK so here is the 502A !
....snip
The handles. Yep, those old leather handles rot and fall apart. Luckily Tek later went to much more durable plastic handles. I had the same issue with my Type 535A. Nothing left but the rusty inner frame. I bought some leather strips and a leather tool kit and made new ones utilizing that inner frame. It came out decent and secure enough to be able to easily lift the scope.![]()


Way too close to the edge. I don't know for leather, but for aluminium rule of thumb is the axis of a fastener should be at least 1.5 times the diameter of the fastener, away from the edge of the part. If you have a whole bunch of rivets holding the parts together, as is often the case, you can afford to have a few of them closer to the edge than normal, like x1 instead of x1.5, but you need to do the paper work / "concession" and send it to the R&D bureau, for acceptance (or not...).
What do you mean? They're Germans. That's how we look when we're really happy & excited.