7503
The Tektronix 7503 is a 90 MHz 7000-series mainframe with three module bays, introduced in 1970. It was effectively replaced by the larger-screen 7603 in 1972.
The 7503 project was managed by Phil Crosby, and was supposed to be a 7504 but with one fewer plug-in. The 7503 was Tek's first scope to use a harmonica connector for inter-board wiring. Prior to this, inter-board wiring had either mainly been point-to-point soldered. Other approaches were taken on certain instruments, for example the 7704, in which pins sticking out of the chassis mate with holes in the boards that receive the pins and make electrical contact. The 7503 also features the 7000-series remote control connector at the rear of the unit.
Key Specifications
| Bandwidth | 90 MHz with 7A11, 7A16 (and faster plug-ins); 75 MHz with 7A12, 7A13, 7A14 |
|---|---|
| Fastest calibrated sweep | 5 ns/Div |
| CRT | T7500 (154-0608-xx), 18 kV total acceleration (+15/-2.96) |
| Vertical modes | Left / Alt / Add / Chop / Right |
| Trigger Source | Left / Vert Mode / Right |
| Calibrator | 4 mV to 40 V in five decade steps, 40 mA, 1 kHz ±0.5% |
| Outputs | Side panel: Vert signal, +Gate, +Sawtooth; At CRT: Camera power |
| Line Voltage | 90-110 V / 104-126 V / 112-136 V / 180-220 V / 208-252 V / 224-272 V, 50—440 Hz |
| Power | Max. 258 W |
| Weight | 21.3 kg / 47 lb (instrument only) |
| Rear connectors |
|
Internals
Like other 75xx and 76xx mainframes and the 7504, the 7503 has a linear power supply, as opposed to the switchmode supplies used in the later 4-slot mainframes. In addition to the +5 V, ±15 V, ±50 V rails common to the 7000 series, internally (not on the plug-in slots) it has a +75 V output not found in later models, and a +150 V instead of the later +130 V.
Pictures
-
Front
-
Plug-in bay
-
Plug-in connectors missing sides
-
Horizontal amp on top
-
Vertical amp on the side
-
Left view, delay cable, CRT
-
Left view, power supply
-
Right view, mains frequency transformer
-
Readout board
-
Right side connector panel
-
Rear
-
-
-
Custom ICs used in the 7503
| Page | Model | Part nos | Description | Designers | Used in |
|---|---|---|---|---|---|
| 155-0011-00 | M012 | 155-0011-00 | clock and chop blanking | Les Larson | 485 • 7313 • 7403N • R7403N • 7503 • 7504 • 7514 • 7603 • AN/USM-281C • 7613 • 7623 • 7623A • 7633 • 7704 • R7704 • 7704A • 7834 • 7844 • 7854 • 7904 • 7904A • R7903 • R7912 • 7912AD • 7912HB • 7934 • 7104 • R7103 • AN/USM-281C |
| 155-0022-00 | M036 | 155-0022-00 • 155-0022-01 | analog multiplexer | Gene Andrews | 147 • 148 • 149 • 335 • 468 • 1430 • 1441 • 1461 • 1900 • 1910 • 2220 • 2221 • 2230 • 5223 • 5403 • 5440 • 5441 • 5443 • 5444 • 5A38 • 7313 • 7403N • 7503 • 7504 • 7514 • 7603 • AN/USM-281C • 7613 • 7623 • 7623A • 7633 • 7704 • R7704 • 7704A • 7834 • 7844 • 7854 • R7912 • 7912AD • 7912HB • 7904 • R7903 • 7904A • 7934 • 7A12 • 7A18 • 7A18A • 7A18N • 7B52 • 7B53N • 7D10 • 7D11 • 7D12 • NT-7000 • P7001 |