There was no 7109. But you may be thinking of
something B&H Engineering (Bernie and Harvey
Horowitz, Monroe, NY) made. They modified a Tek 7104
to take advantage of the exquisite 1 V/Div vertical
deflection sensitivity of the 3GHz CRT. The did this
by removing the entire vertical interface,
differential delay line, and vertical amplifier and
replacing it with a single ended connection using a
proprietary 3GHz amplifier module they developed.
They designed two vertical amplifier plugins
for it. The M2000 was a 3GHz, 50 ohm plugin and the
M3000 was similar except it had a variable delay
feature. The output of both plugins was single ended
and coupled to the mainframe using a SMB connector.
The heart of these two plugins is a single module made
from discrete parts for amplification, the 3002, which
they designed and sold. The module was not Gaussian.
It had terrible overshoot and ringing.
They don’t remember if they made 2 or 3
complete systems for the Navy. I have one of each of
the vertical plugins. I met with them last month to
learn the fate of the mainframes in hopes I could get
one donated to the VintageTEK museum but they were
given to the Navy for whom they were developed and
lost track of them.
From the exterior, the 7104 they modified looks
exactly like a conventional 7104. If you open one up
it would become immediately obvious that the vertical
amplifier was removed and replaced with a 2” x 2”
module which directly drove the vertical deflection
There is no way to verify their claim that this
scope was capable of 3GHz. The technology to do that
didn’t exist in a form that a small company of their
size could afford at that time. Even Tek was unable to
confirm the performance of the CRT beyond 3GHz.
Black, Sent: Friday, July 12, 2013 8:00 PM
I don't think that's what I had in mind. I believe
there was mention of it several years ago here when
there was discussion of the 7109, third party
amplifiers and pushing it's bandwidth to 3 GHz. It
might have been discussion around the old 519
without amplifiers, just talking about the tube
frequency limit. Does anyone else remember it or are
the pixies playing with my mind?