What is a mod BG to 7103 or 7104?


John Griessen
 

I just snagged this at auction in Albuquerque:

https://www.ecosensory.com/tek/7103-mod-bg.jpg

It even works!

So... what is mod BG?


Mark Huffstutter
 

Nice get, John! And working too.

I recall a discussion a few years on MOD BG, but I don't remember whether
It was ever resolved. I will check the archive list. I seem to recall that Dennis
Tillman had found one.

Mark

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of John Griessen
Sent: Friday, August 20, 2021 9:46 AM
To: TekScopes@groups.io
Subject: [TekScopes] What is a mod BG to 7103 or 7104?

I just snagged this at auction in Albuquerque:

https://www.ecosensory.com/tek/7103-mod-bg.jpg

It even works!

So... what is mod BG?


 

On Fri, Aug 20, 2021 at 06:46 PM, John Griessen wrote:


So... what is mod BG
Mod BG description:

//
MOD BG includes modifying the 7104 by adding braces to
the front-panel casting and strengthening the mounting of the crt bezel.
//

/Håkan


John Griessen
 

On 8/21/21 5:22 PM, zenith5106 via groups.io wrote:
//
MOD BG includes modifying the 7104 by adding braces to
the front-panel casting and strengthening the mounting of the crt bezel.
//
/Håkan
Thanks Håkan! So that camera bezel was factory mounted. Mystery solved.


Clark Foley
 

I am not surprised that you found that unit in New Mexico. It was likely the property of Sandia National Labs or Los Alamos National Labs. The nuclear testing facilities in Nevada hosted many contractors such as EG&G and national lab personnel for conducting destructive transient measurements. Although Tek 7912AD was popular in its day, a high-writing rate scope with a film camera configuration was more widely used. A lot of P11 phosphor tubes were sold for that purpose until the 7104/R7103 became available. The problem with hanging a film camera on the scope bezel was the weight of the camera and the vertical lift/drop of the transient event. The scopes were often housed in a big semi-rig trailer on the site. The underground event could easily lift and then drop the trailer. Technicians were elsewhere at the time. The torque would break the bezel or the front casting of the scope. Depending upon the camera used, often a custom device, the scope bezel would be replaced by a suitably stronger one but the scope casting had to come from the Tek factory.

This Mod BG unit might have been purchased with this use in mind in preparation for a test but not put to that particular use or the purchasing department required the mod for all R7103s.


Clark Foley
 

John,

I have posted a photograph of a few R7103s in a rack and ready for an underground test. You will see the same hardware on the bezel. The photo album is named Mighty Oak.
https://groups.io/g/TekScopes/photo/267445/3290449?p=Created,,,20,2,0,0