View source for 7704A

{{Oscilloscope Sidebar|
title=Tektronix 7704A|
image=Tek 7704a trace.jpg |
caption=Tektronix 7704A |
introduced=1972 |
discontinued=1987 |
summary=200 MHz non-storage mainframe|
manuals=
* [http://w140.com/tek-7704a.pdf Tektronix 7704A Manual (PDF)]
}}
The '''Tektronix 7704A''' is a modular oscilloscope in the [[7000-series_scopes|7000 series]] 
that takes two [[7000-series_plug-ins#Vertical plug-ins|7000-series vertical plug-ins]]
and two [[7000-series_plug-ins#Horizontal plug-ins|7000-series horizontal plug-ins]].  
Main designers were [[Luis Navarro]] (electrical) and Bob Shand (mechanical).

The 7704A followed the [[7704]] in 1972, improving bandwidth from 150 to 200 MHz (regular 
model, optimized for transient response) or 250 MHz (option 9, bandwidth-optimized).
The '''R7704''' rack-mount version continued to be named just R7704.

The 7704A has a special modular construction.  At the bottom is the "A7704 acquisition unit",
which contains the power supply, plug-in slots, and main interface board.  On top is
the "D7704 display unit", which contains the CRT, HV power supply, and output amplifiers for
driving the deflection plates of the CRT.  These units detach.  A large multi-pin connector
passes signals and power from the acquisition unit to the display unit.  It is important
not to damage this connector when assembling or disassembling the units.  

An optional component, the [[P7001]] Processing Unit, can be added to a 7704A between the acquisition unit and the display unit.  
The Acquisition Unit of the 7704A, the P7001 Processor, and the Display Unit of the 7704A are connected by the Acquisition-Processor-Display (APD) Interface shown below.

{{BeginSpecs}}
{{Spec | Fastest cal. sweep | 2 ns/Div  }}
{{Spec | Bandwidth | 200 MHz (with [[7A19]]) }}
{{Spec | Calibrator | 4 mV to 40 V in decade steps, 2/20/200/400 mV into 50 Ω, 40 mA; 1 kHz }}
{{Spec | Outputs | Vertical Signal Out (25 mV/Div, 60 MHz), +Sawtooth, +Gate, Cal, camera power, probe power }}
{{Spec | Acceleration voltage | 24 kV }}
{{Spec | Power | 90-132 V or 180-264 V, 48-440 Hz, 180 W max. }}
{{Spec | Weight | 13.6 kg (30 lbs) }}
{{Spec | Size | 34.5 cm × 30.5 cm × 57.7 cm (H×W×L) }}
{{Spec | Options |
* Option 1: No Readout
* Option 3: Extra EMI shielding
* Option 4: Reduced scan CRT (4x5 cm graticule)
* Option 7: Deletes signals out (Vertical signal out, +Sawtooth, +Gate, Z-axis in, remote reset input). Readout always free-running.
* Option 9: Extended bandwidth (250 MHz, trades pulse response)
}}
{{EndSpecs}}

==Internals==
The vertical amplifier in the 7704A uses the [[155-0077-00]] hybrid.

In the 7704A, the [[7000 series readout system|readout board]] is located behind a back panel carrying two [[LEMO S-series connector]]s for probe power.  This placement was intended to allow easy retrofitting of a readout board into an Option 1 instrument, however, the readout board is not a plug-in card − several cables have to be attached to the board.

The 7704A SMPS uses a custom Tek chip ([[155-0067-02]]) to implement the control functions.  For the initial start of the SMPS oscillator on power-up, early 7704As use a diac and later 7704As use a unijunction transistor in the starter circuit.

==Links==
* [[Media:Tekscope 1972 V4 N3 May 1972.pdf  | Luis Navarro, Bob Shand: ''The 7704A-Extended Performance Plus Modularity.'' In TekScope Vol. 4 No. 3, May 1972]] 
* [http://amplifier.cd/Test_Equipment/Tektronix/Tektronix_7000_series_mainframe/7704A.htm 7704A page at amplifier.cd (with repair report, German)] / [https://translate.google.com/translate?sl=auto&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Famplifier.cd%2FTest_Equipment%2FTektronix%2FTektronix_7000_series_mainframe%2F7704A.htm translated]

==Pictures==

<gallery>
Tek 7704a trace.jpg 
Tek 7704A 1.jpg                | 7704A
USA Tektronix 7704A Front0.jpg | 7704A
Tek-7704a-7D01.jpg             | 7704A + [[7D01]] (from advertisement)
Tek-7704a-manual.jpg           | 7704A picture from manual
P7001 apd interconnect.jpg     | APD Interface
Tek-7704A-Interconnect-1.jpg   | Interconnect plug in normal position
Tek-7704A-Interconnect-2.jpg   | Interconnect plug on storage fixture
Tek 7704a p7001 1.jpg          | 7704A with [[P7001]]
Tek 7704a rear1.jpg            | 7704A rear
Tek 7704a rear2.jpg            | 7704A rear
Tek 7704a rear3.jpg            | 7704A rear
Tek 7704a rise 1ns per div.jpg | 7704A Mod 9 rise time with [[7A29]] is 1.25 ns. Sweep was adjusted for exactly 1 ns / div using 1 GHz reference.
</gallery>


[[Category:7000 series non-storage mainframes]]