454: Difference between revisions

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The Tektronix 454 can be seen as an improved [[453]].   
The '''Tektronix 454''' can be seen as an improved [[453]].   
The bandwidth is 150MHz, compared to 50MHz for a 453.   
The bandwidth is 150 MHz, compared to 50 MHz for a 453.   
 
The 454 uses a CRT with distributed vertical deflection plates.   
The 454 uses a CRT with distributed vertical deflection plates.   
Without distributed deflection plates, a CRT designer is forced  
Without distributed deflection plates, a CRT designer is forced  
to trade off deflection sensitivity for deflection speed.   
to trade off deflection sensitivity for deflection speed.   
A CRT with low sensitivity requires a vertical amplifier  
A CRT with low sensitivity requires a vertical amplifier  
with a large output swing.  It is difficult to find transistors that  
with a large output swing.  It is difficult to find transistors that  
have both large voltage swing and high speed.   
have both large voltage swing and high speed.   
Most transistors with high Ft values also have  
 
Most transistors with high f<sub>t</sub> values also have  
quite low collector breakdown voltages.   
quite low collector breakdown voltages.   
So the most practical solution was to use distributed deflection plates,  
So the most practical solution was to use distributed deflection plates,  
and that is what Tektronix did.   
and that is what Tektronix did.   
The 454 weighs 29 pounds and consumes about 130 watts.   
The 454 weighs 29 pounds and consumes about 130 watts.   


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that does not use proprietary hybrid circuits  
that does not use proprietary hybrid circuits  
or proprietary integrated circuits.   
or proprietary integrated circuits.   
(The [[519]] is much faster, but its sensitivity is 10V/div
 
so it isn't really a general-purpose scope.)
With the input sensitivity set to 10mV/div and above, the 454A has a vertical bandwidth of 150MHz.
With the input sensitivity set to 10mV/div and above,  
At 5mV/div it is 100MHz, and at 2mV/div it is 50MHz.  
the 454A has a vertical bandwidth of 150MHz.
It is possible to cascade the channel-1 and channel-2 input amplifiers to obtain a sensitivity of 400uV/div.
At 5mV/div it is 100MHz, and at 2mV/div it is 50MHz.
It is possible to cascade the channel-1 and channel-2  
input amplifiers to obtain a sensitivity of 400uV/div.
In that configuration, the vertical bandwidth is 33MHz.
In that configuration, the vertical bandwidth is 33MHz.


The 454 was [[introduced in 1967|introduced in March 1967]].   
The 454 was [[introduced in 1967|introduced in March 1967]].  The 454A was [[introduced in 1971]].
The 454A was [[introduced in 1971]].


*[http://w140.com/mmm/tek-454.pdf Tektronix 454 Manual (PDF)]
*[http://w140.com/mmm/tek-454.pdf Tektronix 454 Manual (PDF)]
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Image:454 vert out.gif
Image:454 vert out.gif
</gallery>
</gallery>
[[Category:400 series scopes]]
[[Category:Specifications needed]]

Revision as of 03:44, 14 June 2014

The Tektronix 454 can be seen as an improved 453. The bandwidth is 150 MHz, compared to 50 MHz for a 453.

The 454 uses a CRT with distributed vertical deflection plates. Without distributed deflection plates, a CRT designer is forced to trade off deflection sensitivity for deflection speed.

A CRT with low sensitivity requires a vertical amplifier with a large output swing. It is difficult to find transistors that have both large voltage swing and high speed.

Most transistors with high ft values also have quite low collector breakdown voltages. So the most practical solution was to use distributed deflection plates, and that is what Tektronix did.

The 454 weighs 29 pounds and consumes about 130 watts.

The 454 has a 140ns delay line in the signal path after the input channel switching and before the main vertical amplifier. There is a phase equalizer after the delay line to mitigate the harm done to pulse fidelity by the delay line.

The 454 is the fastest general-purpose Tektronix scope that does not use proprietary hybrid circuits or proprietary integrated circuits.

With the input sensitivity set to 10mV/div and above, the 454A has a vertical bandwidth of 150MHz. At 5mV/div it is 100MHz, and at 2mV/div it is 50MHz. It is possible to cascade the channel-1 and channel-2 input amplifiers to obtain a sensitivity of 400uV/div. In that configuration, the vertical bandwidth is 33MHz.

The 454 was introduced in March 1967. The 454A was introduced in 1971.