062 Firmware Revision History (Improved Models)
[ Note 1: Firmwares for the improved models are not compatible to the old models becasue hardware was changed. ]
Fixed a bug in Rolling Mode (when timebase is slower than 20ms/Div). This bug caused uneven delay between samples so that signal frequency appeared higher.
Up to 20MSa/s Equivalent-Time Sampling was implemented. Now you are able to see much detailed waveforms that you could not see with earlier version of firmwares.
For example, This
a 400KHz square signal displayed with 2MSa/s real-time sampling (the maximum of old firmware). And
is the same signal displayed with 20MSa/s equivalent-time sampling.
How to Use:
When time base is set to 2us or faster equivalent-time sampling method is used automatically, regardless of trigger mode setting.
However, two conditions must be met before the equivalent-time sampling can work for you. 1 ) The signal to be watched must be a repeative signal. 2 ) Trigs must happen. This is because
with equivalent-time sampling a displayed waveform is actually constructed by samples taken at diffenent spots from multiple cycles. Trigs serve as reference points so that correct time relation
between samples can be established and waveform can be correctly constructed. If there is no trig you will not be able to see display refreshes. So it is recommended first to use real-time
sampling (i.e. setting time base to 5us or slower) to get a rough idea of the signal you are not fimiliar with. Then set to equivalent-time sampling and change trigger level to make trig happen.
1. 062 oscilloscope has only 1MHz analog bandwidth. So you will not be able to see signal higher than that even though the 20MSa/s sampling rate
is good for frequency of 3 -4 MHz or higher. This is a bit wasted. But still for signal under 1MHz now you can see much more details that you did not see with old firmware. Look at this
. It was only one division with old firmware and now it is expanded to one full screen.
2. For signals close to 1MHz you will find trig is difficult. This is because there is a Low Pass Filter (R30, C23) for the trigger. The purpose of this filter
is for stablizing trigs and its cut-off frequency was set to about 120KHz. For frequency greater than 500KHz signal level is greatly reduced by this filter before reaching the trigger.
To solve this problem we can change the values of R30 and C23. For example, R30 can be changed to 470 ohm and C23 to 330pF. But after this change you will find the trig is not that
stable for low frequency signals (you may see waveform jumping).
First official release