Re: What is a mod BG to 7103 or 7104?

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.

Join to automatically receive all group messages.