HP 3336A Operating Manual page 55

Operation Model 3336A/B/C
b. Amplitude.
After receiving ''IAM"'', the -hp- 3336 will send its output amplitude, in
dBm, formatted as follows:
@
AM 600000 DD.DD@ DB CR LF&EOI
A minus sign will replace the first zero if
the value is less than @ dBm.
d. Sweep Start Frequency. After receiving ''IST'', the -hp- 3336 will send the frequency
in Hz, formatted as follows:
T1 000002DD.DDD SE CR LF&EOI
3336A 75 ohm D
150 ohm D
600 ohm D
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