Test Equipment Anonymous (TEA) group therapy thread

[bsdphk]

I need help identifying a Tek scope plugin, for the most obscure reason you can possibly imagine...

First two (huge) photos:

https://datamuseum.dk/bits/30006763

https://datamuseum.dk/bits/30006749

These photos were taken in Stockholm in early 1955 by Bent Scharøe Petersen, and show the setup he used to investigate if the brand new "magnetic core memory" technology was any use for the IAS-derived computers being built in Sweden and Denmark at the time (BESK, SMIL, DASK)

There are also photos of scope-traces, with handwritten descriptions which either read "20µs/cm" or maybe "20ns/cm":

https://datamuseum.dk/bits/30006678

So which is it ?

The scope is a Tek 535, which does not seem to have a serial number.

But I have been unable to figure out if the plugin is 53A or 53B ?

My personal guess is that it "20ns/cm", mostly because "20µs/cm" would make the signals very slow compared to the IAS-derived computers.

If it is 20ns/cm, the signal is 25 MHz, and as I understand it, the 735 should be able to do that with a 53B ?

Thanks for any help.

PS: All the 200+ pictures are here:

https://datamuseum.dk/wiki/Bits:Keyword/PERSONS/BENT_SCHAR%C3%98E_PETERSEN/PHOTOS

[K0ELB]

If I were a betting man, I’d say it’s the European made Type 53/54B.
Per the Tekwiki:
“ Like Type A, Type B has its roots in the 1954 introduction of the 531 and 535, as the five-tube Type 53B, with 1x bandwidth of DC to 10MHz (limited by the mainframe) and 10x-AC bandwidth of 2 Hz to 9 MHz.”

Which is exactly what is on that plugin. https://w140.com/tekwiki/wiki/B

—-edited to add more information—-

[factory]

There is no Tek 735 on the wiki, looks more like an early 535 or 545 to me. 

David

[bsdphk]

Sorry, typo!  Yes, it's a 535

[Vince]

I never heard of a 735 Tek scope ? Are you sure ?

Looks 100% to me like a bog standard 535 scope, an early one, pre-round cabinet.

Neither Google nor Tekwiki know of a 735 Tek tube scope, but I am all for learning new exciting stuff if it did actually exist ! 

The 535 is good for 10MHz, 15MHz depending on serial number.

https://w140.com/tekwiki/wiki/535

The plug-in is easy, no room for error. It's a type 53B, good for 10MHz tops, it's even written on it, see your picture ! 

https://w140.com/tekwiki/wiki/B


EDIT : messages collided... OK so no mystery 735  then...