User manual

Publication No. 980935 Rev. M 3152B User Manual
Astronics Test Systems Introduction 1-13
• EXT 10MHz: A TTL level external 10 MHz reference OR a
phase control input for use in PLL mode (software selectable)
The 3100M-3152B
has the same pattern as described above for
the 3100R-3152B but has the following additional functions:
• LAN (RJ-45): LAN connection for software control
•
USB 2.0 (Type A): Memory stick device port for firmware
upgrade or for loading external data into memory
OUT
PUT (OUT)
The OUTPUT connector is the main output, and is used for fixed
(pre-defined) or modulated waveforms up to 100
MHz, and for
arbitrary or sequenced waveforms with up to 300 MS/s.
Output impedance is 50Ω
, and the amplitude accuracy is calibrated
for a connection to a 50Ω load and a load >100 kΩ
. The amplitude
is doubled for high-impedance loads (greater than 100 kΩ).
SYNC
OUT
(SYNC)
The SYNC OUT connector outputs a single TTL-level pulse for
synchronizing other instruments, such as an oscilloscope, to th
e
output waveform. The SYNC signal always appears at a fixed point
relative to the waveform. The location of the SYNC
signal relative
to the waveform is programmable, as is the pulse width. When the
sweep or any other modulation function is enabled, the SY
NC
connector is also useful as a marker output.
TRIG/PLL
IN
(TRG/PLL)
The TRIG/PLL IN connector accepts signals that stimulate the
generation of output waveforms. The 3152B ignores this input
when operating in Continuous mode. When
placed in Trigger,
Gat
ed, or Burst mode, the trigger input is active, and the 3152B
waits for the proper condition to trigger the instrument. In Trigger
and Burst modes, the TRIG/PLL input is edge-
sensitive, so that a
signal transition will trigger the 3152B. The direction of the
transition is programmable. In gated mode, the TRIG/PLL signal is
level sensitive. The output waveform is enabled when the
TRIG/PLL signal voltage is beyond a threshold voltage. The
threshold voltage and direction are pro
grammable within the range
of -10 V to +10 V.
When the PLL function is selected, this input feeds the reference
signal to the PLL circuit. The PLL input must be stable and
repeatedly cross the trigger level threshold setting. Signals having
a low slew rate may cause jitter because of noise. Therefore, make
sure that the transition time is fast enough to minimize jitter.
The TRG/PLL IN input is also used in FSK, ASK, and PSK modes,
where the output shifts between two frequencies, amplitudes, or
phases. The output signal has the nominal frequency, amplitude,