BIG ol tektronix scope 555 - need it gone - make an offer

[Norman Jaffe]

I was doing something similar, on a PDP8/L driving a Tektronix scope with a camera attached, using code written in Focal - University of Washington, 1972. 
I learned a great deal about font generation, given that the code had to trace out each letter shape via X, Y coordinates... 

From: "cctalk" <cctalk at classiccmp.org> 
To: "Toby Thain" <toby at telegraphics.com.au> 
Cc: "cctalk" <cctalk at classiccmp.org> 
Sent: Tuesday, December 11, 2018 1:33:52 PM 
Subject: Re: BIG ol tektronix scope 555 - need it gone - make an offer 

> On Dec 11, 2018, at 3:30 PM, Toby Thain <toby at telegraphics.com.au> wrote: 
> 
> On 2018-12-11 9:15 AM, Paul Koning wrote: 
>> 
>> 
>>> On Dec 11, 2018, at 7:59 AM, Toby Thain via cctalk <cctalk at classiccmp.org> wrote: 
>>> 
>>> On 2018-12-11 1:17 AM, devin davison via cctalk wrote: 
>>>> The line about being used with an early computer as a display caught my 
>>>> eye. How would it be used as a display, what kind of graphics capability 
>>>> would it have? is there an interface for the thing for the pdp 11 or a 
>>>> modcomp? Those are the old systems i have on hand that i might be able to 
>>>> interface to it. 
>>> 
>>> A scope is at heart an electrostatic CRT with X and Y deflection ... 
>>> 
>>> For digital computers, output is point plotting, vector drawing, and/or 
>>> character generation depending on the sophistication (= cost) of the 
>>> hardware involved. You'd also need to find or write suitable software :) 
>>> 
>>> Yes, there were interface cards for PDP-11, such as AA11 (dual DACs). 
>> 
>> I made such a setup in college: we had an 11/20 with AA11 (and other lab I/O gear). I hooked those up to the X/Y inputs of a scope, and a digital I/O line to the Z input. Then loaded coordinate pairs into a buffer on the RC11 disk, which was set up to do DMA directly to the AA11 data CSR. Worked nicely, and with low overhead on a machine that certainly could not afford to do refresh in software. 
> 
> Curious what year that was, if you don't mind disclosing? 

1974, at Lawrence University which had that 11/20 (with 8 kW of memory, DECtape, RC11, AA11, AD01, DR11, and ASR33) in the physics lab. 

paul