The Tektronix 7A29 is a 1 GHz single-channel vertical plug-in for 7000-series scopes. It is primarily intended for the 7103 and 7104. Like with the 7A19, a variable signal delay was available as an option.
The 7F10 uses the 7A29's amplifier board after the optical/electrical converter.
|Bandwidth||1 GHz (in 7104)|
|Input impedance||50±1 Ω, VSWR <1.2:1 from DC to 1 GHz (10 mV/Div: 1.4:1, Opt.4: 1.5:1)|
|Max. input||max. 10 VRMS or 1 Ws pulses not exceeding 50 V; max. 100 V additional DC component in AC mode|
|Deflection||10 mV/div to 1 V/div, 1-2-5, ±2%; variable 2.5:1|
|Recommended probes||P6056 (×10), P6057 (×100)|
|Options||Option 4: variable delay (1 ns)|
It uses a "feed-beside" scheme implemented with standard low-frequency operational amplifiers to compensate for low-frequency anomalies in the frequency response that are attributed to transistor heating.
The input connector is a special Tek-made part that is exactly 50 Ω. Typical BNC connectors are around 52 Ω.
The 7A29 does not use the ±50 V supplies provided by the mainframe.
Although the 7A29 has a VARIABLE gain control, this control has the undesirable side-effect of also affecting bandwidth. See bandwidth versus VARIABLE gain plot below.
- Tektronix 7A29 teardown - nice detailed pictures of attenuator internals
- Tek 7A29P @ amplifier.cd including internal pictures