Rohde Schwarz Rohde & Schwarz HMO1002 2-channel oscilloscope, Digital Storage oscilloscope, 21-1002-RS00 数据表

window displays up to 40 detected data values (limited 
by processor performance). How much data is currently 
displayed depends on the displayed time window and the 
current sampling rate. If peak detection is activated, each 

column displays up to 20 pairs of min/max values. The 
memory depth always corresponds to the maximum ac-
quisition memory. The displayed sampling rate is identical 
with the current sampling rate. Peak detection is used if 
the displayed time window contains more data than 40 * 
signal window columns in the acquisition memory or min/
max data in the acquisition memory.

This function is the default setting and offers the best 
compromise between maximum repeat rate and maximum 
sampling rate (selection of memory depth). Each column 
in the signal window displays up to 10 captured data va-
lues. How much data is currently displayed depends on 
the displayed time window and the current sampling rate. 
When peak detection is activated, each column displays 
up to 5 pairs of min/max values. The memory depth is at 
least twice as much as the storage capacity set for the 
maximum repeat rate (limited by the maximum acquisition 

Fig. 5.3: Example figure of AM modulated signal with max. sampling rate

memory). The displayed sampling rate corresponds to the 
current sampling rate divided by the amount of data skip-
ped while loading from the acquisition memory. If peak 
detection is activated, the displayed sampling rate corres-
ponds to the current sampling rate.

All settings apply the identical current sampling rate 
(sampling rate used to write to the acquisition memory). 
In STOP mode it is also possible to change menu items. 
This does not impact the current memory depth but the 
amount of displayed data will be adjusted. Peak detection
is also activated in STOP mode (time base in microse-
conds). In time bases displaying each sampling point, all 
three settings behave identically (except used memory 
depth and signal update rate). Table 5.1 displays advanta-
ges and disadvantages of each setting.

Finally, it needs to be mentioned that this menu repla-
ces the adjustable memory depth, a standard for other 
manufacturers. An adjustable memory depth is intended 
to allow users to understand the relation between me-
mory depth, time base and sampling rate and to evaluate 
advantages and disadvantages. With this option, the 
oscilloscope always captures signals with the maximum 
sampling rate. This allows users in STOP mode to zoom 
in retrospectively, even at the maximum repeat rate. It is 

Fig. 5.4: Example figure of AM modulated signal with automatic setting

Maximum waveform rate:

 

ı Many captures in one image 

 

ı Rare events can be detected more 

quickly in connection with per- 
sistence

 

ı Quick response to Operation or  

change in signal

 

ı Low noise band

 

ı High aliasing risk 

 

ı Low accuracy of details

 

ı Low accuracy of measurements  

due to reduced amount of data

 

ı Search for rare events

 

ı Displaying modulated signals

Maximum sample rate

 

ı Maximum accuracy of details

 

ı Lowest aliasing risk

 

ı High accuracy of measurements

 

ı Slow response to operation or  

change in signal

 

ı Low signal update rate

 

ı Higher visibility of noise

 

ı For signals with high frequency  

parts

 

ı Assessment of small signal  

details

Automatikc:

 

ı Average signal update rate

 

ı Reasonably smooth operation

 

ı Good accuracy of measurements

 

ı Low noise band

 

ı Possible aliasing

 

ı Default application

Table 5.1: Advantages and disadvantages of each setting.