Hi GerhardMine does the same , or it did before the power supply went into tick mode , not had time to fix that yet . I put it down to expectations of a bi-stable screen like that in a 564 or a 549

Has anyone experience with the TEK 7834 400 MHz mainframe? About 20 years ago I bought a used 7834 mainframe for the 7S11/7T11 plug-ins. At that time I wondered about the storage function. When

I had an interesting situation which I done that as well On the PCB board of DC electronic load a white dot was marked to indicate pin 1, however on the IC socket it indicated the pin on the opposite

Actually, you can see the notch and STILL install it backards. Been there, done that. Paul -- Paul Amaranth, GCIH | Manchester MI, USA Aurora Group of Michigan, LLC |

Thanks for the correction and the valuable information The reason for confusion is that In the past I have dealt with IC's that referenced pin 1 with a circle, you can see this in the link

see www.hakanh.com/dl/docs/hardtofind/200-0950-00.pdf /Håkan

I looked inside my 7704A and verified that all the 200-0950-00 COVER, ELEC CONN:PLASTIC are there. I don't see them so fragile, and they are solidly attached (inserted?) to the connector body.

My saying "*About* 1 inch by 3 inch" indicates that it was just a guesstimate. I was giving an approximate size to eliminate any of the other parts, particularly any "prismatic" parts, from the

The notch is pin 1, lower left corner in your photo. the part number is near pin 7. This is a quad 2 input NAND gate device from the fist vintage of 7400 series TTL. Made in 1972. Tom Bowers

The notch identifies pin 1 which is at the lower left. That's also a quad nand gate, not an op amp. The circle is a mold mark. -- Paul Amaranth, GCIH | Manchester MI, USA

I meant to say Quad Dual Input NAND device. Carl

It is not an op amp.  It is a quad nand gate.  On round devices, the tab is the last pin. Carl Hallberg (W9CJH)

https://groups.io/g/TekScopes/album?id=245683 Here is a rather unusual design at least for me. This chip contains both the notch and the circle, I want to say the notch is pin 1 but I am not 100%

Yes, Steve, that is what I understand to be the item in question. However, I wouldn't particularly call them "pins", more "connectors" as they are thin and flat; I think of "pins" as being more

Colin and David, If you look at eBay item: 133386313435 it is the plug-in backplane for a 7854. In the fourth photo, I believe it shows one of the connectors that is missing the cover on one side of

Thank You, David, I am now un-flummoxed. It is exactly the part that I was thinking of, but the 3 inch measurement is way too short. As you suggest 4 inch is about right. These parts are also used on

For avoidance of doubt this is p/n 200-0950-00 shown on the mechanical parts breakdowns in all the 7000 series Service manuals. There are two of these used on each plugin socket on the main interface

I thought that I knew what you were talking about until you gave the size as 1 inch by 3 inches. I am now flummoxed, because that isn't the size of the plastic parts that keep the (gold-plated)

I was not aware of this YouTuber (TomTekTests) until I stumbled across this video on a 570 restoration. https://youtu.be/AphQLWbN8nI Here is part 2: https://youtu.be/U2GVbmi4Wso Makes me want a

Well said, Yachad, especially setting off professionalism against rigid traditionalism. Doing things in an unorthodox way can work! You gave very clear instructions. And you even express my stated