A: Difference between revisions
Vintage dave (talk | contribs) mNo edit summary |
No edit summary |
||
Line 26: | Line 26: | ||
tube by a 5 nF capacitor. This "cross-bootstrapping" extends the high-frequency response. | tube by a 5 nF capacitor. This "cross-bootstrapping" extends the high-frequency response. | ||
Although 1959 was the first year one could find a "Type A" in the catalog, the same | Although 1959 was the first year one could find a "Type A" in the catalog, the same instrument with earlier "Type 53/54A" | ||
instrument with earlier "Type 53/54A" nomenclature was in the August 1956 | nomenclature was in the August 1956 Short Form catalog, and its Type 53A ancestor was in the August 1954 catalog which | ||
Short Form catalog, and its Type 53A ancestor was in the August 1954 | introduced the first 500-series scopes, the [[531]] and the [[535]]. | ||
catalog which introduced the first 500-series scopes, the [[531]] and the [[535]]. | |||
Type 53A has only three tubes, no [[T-coil peaking|T-coils]] or cross-bootstrap, and a bandwidth of 10 MHz in the 530 mainframes. | Type 53A has only three tubes, no [[T-coil peaking|T-coils]] or cross-bootstrap, and a bandwidth of 10 MHz in the 530 mainframes. | ||
Catalogs don't list 53A performance in the 540 mainframes, but the Factory Cal Procedure says | Catalogs don't list 53A performance in the 540 mainframes, but the Factory Cal Procedure says 20 MHz. | ||
Type A was the first letter-series plug-in to be discontinued, in 1962. | Type A was the first letter-series plug-in to be discontinued, in 1962. |
Revision as of 23:20, 25 September 2021
The Tektronix Type A is a single-channel preamp introduced in 1959 for 500-series scopes. It provides two inputs and has a switch to select between them. A 545 with a Type A has a system risetime of 18 nanoseconds and a bandwidth of 20 MHz.
The plug-in uses a 12AU6 in the front end as a cathode follower. This input stage drives the second stage, a differential amplifier made of two more 12AU6 tubes. The second stage drives the output stage, a pair of cathode followers made of both halves of a 12AT7 tube. The plate of each output tube is connected to the cathode of the other output tube by a 5 nF capacitor. This "cross-bootstrapping" extends the high-frequency response.
Although 1959 was the first year one could find a "Type A" in the catalog, the same instrument with earlier "Type 53/54A" nomenclature was in the August 1956 Short Form catalog, and its Type 53A ancestor was in the August 1954 catalog which introduced the first 500-series scopes, the 531 and the 535. Type 53A has only three tubes, no T-coils or cross-bootstrap, and a bandwidth of 10 MHz in the 530 mainframes. Catalogs don't list 53A performance in the 540 mainframes, but the Factory Cal Procedure says 20 MHz.
Type A was the first letter-series plug-in to be discontinued, in 1962. Customers were told to get Type B instead, although it cost more.
Specifications
Please add
Pictures
-
53A front
-
53A chassis
-
53A chassis bottom
-
53/54A front
-
53/54A top (dirty, missing two tubes)
-
53/54A bottom
-
53/54A left
-
53/54A rear
-
Type A front
-
schematic