Tektronix 1720

Theory of Operation
4–24
1720/1721
pull-down transistor. C6 speeds up the amplifier by coupling ac signals to the
base of Q3. CR2 and R41 protect the amplifier during crt arcing.
The pinout for the CRT is shown in Figure 4-3.
Pin Description
1.....................................Filament (f)
2.....................................Cathode (k)
3.......................................GRID (g1)
4...................................FOCUS (g3)
5.....................................ASTIG (g4)
6.....................................GEOM (g5)
7..........................VERT PLATE (y2)
9..........................VERT PLATE (y1)
11......................HORIZ PLATE (x2)
12...........................1st ANODE (g2)
13......................HORIZ PLATE (x1)
14...................................Filament (f)
14
13
12
11
9
7
6
54
3
2
1
Figure 4-3: Pinout of the CRT Socket
CRT