I don't know the G serial number at which Tek switched from UHF to BNC*, but the 1962 catalog shows UHF while 1963 is BNC**. I think I have a newer manual at home, I'll try to remember to look.
There was a mod kit for converting instruments in the field. I have at least one modded scope and plugin. Yours too, most likely, as Tek would not have sold instruments with such an obvious bodge.
* For what it's worth, the 535A mainframe switched at 31260.
** Some old models were not updated.
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of cmjones01 <chris@...>
Sent: Wednesday, October 24, 2018 11:59 AM
Subject: Re: [TekScopes] Type G plugin versions
On Wed, Oct 24, 2018 at 10:21 AM, Dave Seiter wrote:
My G (serial number just under 10K) has holes in the front panel for theMy G also has BNC connectors. If it's anything like the other 500 series equipment, I think the transition was in the mid-to-late 1960s. My 535A has factory-fitted BNCs as well.