7854
The Tektronix 7854 Waveform Processing Oscilloscope, introduced in 1980, is a 400 MHz combined analog / digital mainframe in the 7000 series that takes two vertical and two horizontal 7000-series plug-ins. In addition to a conventional analog (real time) scope, it contains an equivalent-time sampling 10-bit digitizer and a programmable waveform processor with GPIB interface.
The waveform processor can be programmed using a detachable calculator-style keyboard, using postfix operators ("reverse Polish notation" like HP calculators) that operate on entire waveforms, not just individual numbers.
Key Specifications
| Bandwidth | (analog) 400 MHz |
|---|---|
| Fastest cal. sweep | 500 ps |
| Sample rate | 500 kHz (stores repetitive waveforms up to 400 MHz) |
| Resolution | 10 bit |
| Acquisition depth | 128, 256, 512 or 1024 points |
| Memory capacity | 2048 waveform points in up to 16 waveforms (optional expansion to 5120 points and 40 waveforms) |
| Single shot | events and pretrigger up to 50 µs/div ("2.5 µs/point") with the 7B87 Time Base |
| CRT | 154-0644-05, P-31, or 154-0893-09, P-11 |
| Features |
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Internals
The acquisition system uses what Tektronix termed a "display-oriented random sampling digitizing technique". It simultaneously digitizes a pair of X and Y signal values at a rate of 3.5 µs/point, using Schottky diode bridge based sample/hold circuits and a single 10-bit successive-approximation ADC. The Y sample value is then written into the memory location addressed by the X value, using DMA.
The CPU in the 7854 is a Texas Instruments TMS9900 16-bit microprocessor, known from the infamous TI-99/4 home computer of the late 70s, with 32+6KByte ROM and 8KByte RAM.
Software
Prices
1990: $17,000
Links
Pictures
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Waveform Calculator Keyboard
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Digital section in the 7854
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7854 Vertical Amp Board
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7854 Horizontal Amp Board
