The 7A15 is a single channel, 80 MHz general-purpose vertical amplifier for 7000-series scopes.
The AM-6565/U (aka 7A15N11) is the military version of this amplifier (without readout). A Department of the Army Technical Bulletin (see links section) suggests that it was used with the 7603 and its military version (the AN/USM 281C).
The 7A15A is a fully discrete design (i.e. no integrated circuits), built mostly from BJTs, with a 151-1032-00 dual JFET as the front-end buffer.
|Bandwidth||0 – 80 MHz (DC), 1 Hz – 80 MHz (AC)|
|Deflection||5 mV/Div to 10 V/Div in 1–2–5 sequence|
|Input impedance||1 MΩ // 20 pF|