DSA815

class tam.DSA815(visa_rm, visa_id)[source]

Create an instance of DSA815.

Parameters:

visa_rm – A reference to a Visa resource manager. As returned (for example) by a call to pyvisa.ResourceManager().
visa_id (str) – The ID of the analyzer to connect with.

property atten: The analyzer input attenuator setting in dB.

property atten_auto: The auto setting mode for the analyzer input attenuation.

property detector_mode: The analyzer detector type. This should be one of ['NEG', 'NORM', 'POS', 'RMS', 'SAMP', 'VAV', 'QPE']

property freq: The analyzer sweep centre frequency in MHz.

property fspan: The analyzer sweep frequency span in MHz.

initialize()[source]

Initialize the analyzer state.

Sets the analyzer to single sweep mode, sets the sweep averaging mode and number of sweeps to average over. Also sets the reference level to the default value.

measure_next_pwr()[source]

Measure the power and freq. of the next highest peak.

This assumes that the measure_pwr method has already been called. For example:

>>> sa.vavg = 5
>>> sa.fspan = 0.1
>>> sa.ref_level = 10.0
>>> sa.measure_pwr(250.0)
(2.732128, 250.000166)
>>> sa.measure_next_pwr()
(1.986321, 250.050134)

Note that if the analyzer cannot find another peak the cal to measure_next_pwr will return the power and frequency values for the first peak.

Returns:: A tuple of two floats with the power (in dBm) of next highest peak being first and the second being the frequency (in MHz) of the peak.

measure_pwr(freq)[source]

Measure the signal power of the peak near the specified frequency.

This makes use of the spectrum analyzer peak search function to find the maximum signal value in the currently set span. This assumes that the relevant spectrum analyzer configuration has already been set. For example:

>>> sa.vavg = 5
>>> sa.fspan = 0.1
>>> sa.ref_level = 10.0
>>> sa.measure_pwr(250.0)
(2.732128, 250.000166)

Parameters:: freq (float) – The centre frequency to make the measurement (in MHz).
Returns:: A tuple of (pwr, freq) where pwr is the measured power (in dBm) of the signal at frequency freq (in MHz).

property mixer_level: The maximum power (in dBm) at the input mixer. The valid range of values is -30 to 0 dBm in increments of 10 dB.

property rbw: The analyzer resolution bandwidth in Hz.

property rbw_auto: The auto setting mode for the resolution bandwidth.

property ref_level: The analyzer reference level in dBm.

property scale: The scale of the analyzer power axis in dB. The valid range of values is 0.1 to 20 dB.

property start_freq: The analyzer sweep start frequency in MHz.

property stop_freq: The analyzer sweep stop frequency in MHz.

sweep()[source]: Carry out a sweep using the currently set analyzer settings.

property sweep_time: The analyzer sweep time in seconds.

trace_data()[source]

Retrieve the current analyzer trace data.

Returns:: A list of float values.

property unit: The unit of measurement for the analyzer y-axis. This should be one of [DBM, DBMV, DBUV, V, W].

property vavg: The number of sweeps to average over.

property vbw: The analyzer video bandwidth in Hz.