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Since the '''firmware''' version [[http://athome.kaashoek.com/tinySA/DFU/|1.1-94]] there you have a '''trigger pulse''' output on SMA connector '''HIGH''', when you set '''LOW''' to '''Output'''.. If the electic load is high (>22KOhm) the '''amplitude''' is about '''3 V'''. ||<tablestyle="float:right;">[[attachment:tinySA-LOW-Output.jpg|{{attachment:tinySA-LOW-Output.jpg|attachment:tinySA-LOW-Output.jpg|width="320"}}]] ||

Since the '''firmware''' version [[http://athome.kaashoek.com/tinySA/DFU/|1.1-94]] you have a '''trigger pulse''' output on SMA connector '''HIGH''', when you set '''LOW''' to '''Output''', see the '''screen shot''' to the right.

If the electric load is high (>22KOhm) the '''amplitude''' is about '''3 V'''.
Line 6: Line 10:

The tinySA '''LOW output level''' is level '''normalized''' over the whole 0-350 MHz output range but only if the chosen output level is '''-15dBm or lower'''.

Then the amplitude deviation is about +/- 1 dB.

When you want to sweep, tap on '''SWEEP'''.

.

||<tablestyle="float:right;">[[attachment:tinySA-LOW-SweepMode.jpg|{{attachment:tinySA-LOW-SweepMode.jpg|attachment:tinySA-LOW-SweepMode.jpg|width="320"}}]] ||
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The tinySA scans its input frequency range either in start/stop mode or in center/span mode. The number of points displayed is always 290. The number points scanned is minimum 290 but when the [[TinySA-RBW|RBW]] is set to automatic the number of points scanned is increased when needed to ensure coverage of the whole frequency range If I want to test the '''frequency response''' of '''channel 1''', the '''LOW output''' is connected via '''coax cable''' 50 Ohm to the DSO channel 1, '''terminated''' with a '''50 Ohm load'''.
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 * '''START''' sets the scanning to start/stop mode and sets the start frequency
 * '''STOP''' sets the scanning to start/stop mode and sets the stop frequency
 * '''CENTER''' sets the scanning to center/span mode and sets the center frequency
 * '''START''' sets the scanning to center/span mode and sets the frequency span
 * '''CW FREQ''' sets the scanning to center/span mode, sets the span to 0Hz and sets the center frequency
 * '''PAUSE SWEEP''' pauses the scanning
 * '''BACK''' moves one level up in the menu structure
'''Channel 2''' is connected with a DSO probe to output '''HIGH''', in order to trigger the scan. The connection was made with a PCB edge SMA female plug.
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The scanning is limited to the frequency range of the selected [[TinySA-MODE|MODE]]. In this case the '''sweep scan width''' was set to '''150 MHz'''.

The '''sweep time''' was set to '''1.5 s'''.

See below the scan of '''Channel 1'''.

||<tablestyle="float:right;">[[attachment:tinySA_Hantek5072_Frequency_Response_CH1.jpg|{{attachment:tinySA_Hantek5072_Frequency_Response_CH1.jpg|attachment:tinySA_Hantek5072_Frequency_Response_CH1.jpg|width="800"}}]] ||

The '''aquire mode''' was set to '''peak''' in order to just show the '''envelope'''.

You see 2 curves '''symmetric''' to the horzontal axis. Uusually you take care about the '''upper half''' only.

The '''blue trace''' (Channel 2) shows the '''trigger pulse'''.

Note: Above 70 MHz the curve shows some overshoot, becaus of tuning.

The next screen shot shows the '''frequency response''' of '''Channel 2''' (not tuned).

||<tablestyle="float:right;">[[attachment:tinySA_Hantek5072_Frequency_Response_CH2.jpg|{{attachment:tinySA_Hantek5072_Frequency_Response_CH2.jpg|attachment:tinySA_Hantek5072_Frequency_Response_CH2.jpg|width="800"}}]] ||

So make the '''DSO setup''' easier, following the '''setup parameters'''.

'''tinySA''':

Mode: LOW OUT

Level: -15dBm

Sweep span 150MHz

Sweep time 1.5s

'''DSO''':

Utility: Page 2/3: Time set to actual time

Acquire: Mode: Peak

Display: Page 2/2, Grid Intensity: 15, Wave Intensity: 12

 * '''Measuring CH1''' (CH2 probe on tinySA HIGH)
  * CH1 Frequency response: probe: 1:1 50 Ohm load, 20mV/div, DC
  * CH2 Trigger: 10:1, 2V/div, DC
  * Horizontal: 80ms/div->Menu: Page2/2 Time/Div: Fine: adjust SEC/DIV to 100ms/div
  * Trigger: Edge, CH2, Rising, Mode: Normal, DC, 1V

 * '''Measuring CH2''' (CH1 probe on tinySA HIGH)
  * CH1 Trigger: 10:1, 2V/div, DC
  * CH2 Frequency response: probe: 1:1 50 Ohm, 20mV/div, DC
  * Horizontal: 80ms/div->Menu: Page2/2 Time/Div: Fine: adjust SEC/DIV to 100ms/div
  * Trigger: Edge, CH1, Rising, Mode: Normal, DC, 1V

-- RudolfReuter <<DateTime(2021-02-24T16:13:29Z)>>

Scan LOW Synch

attachment:tinySA-LOW-Output.jpg

Since the firmware version 1.1-94 you have a trigger pulse output on SMA connector HIGH, when you set LOW to Output, see the screen shot to the right.

If the electric load is high (>22KOhm) the amplitude is about 3 V.

This trigger pulse is used to synchronize an oscilloscope sweep scan, in order to get a steady display.

The tinySA LOW output level is level normalized over the whole 0-350 MHz output range but only if the chosen output level is -15dBm or lower.

Then the amplitude deviation is about +/- 1 dB.

When you want to sweep, tap on SWEEP.

.

attachment:tinySA-LOW-SweepMode.jpg

Application DSO Frequency Response

My first idea to test this new feature was to measure my Digital Storage Oscilloscope (DSO) frequency response.

If I want to test the frequency response of channel 1, the LOW output is connected via coax cable 50 Ohm to the DSO channel 1, terminated with a 50 Ohm load.

Channel 2 is connected with a DSO probe to output HIGH, in order to trigger the scan. The connection was made with a PCB edge SMA female plug.

In this case the sweep scan width was set to 150 MHz.

The sweep time was set to 1.5 s.

See below the scan of Channel 1.

attachment:tinySA_Hantek5072_Frequency_Response_CH1.jpg

The aquire mode was set to peak in order to just show the envelope.

You see 2 curves symmetric to the horzontal axis. Uusually you take care about the upper half only.

The blue trace (Channel 2) shows the trigger pulse.

Note: Above 70 MHz the curve shows some overshoot, becaus of tuning.

The next screen shot shows the frequency response of Channel 2 (not tuned).

attachment:tinySA_Hantek5072_Frequency_Response_CH2.jpg

So make the DSO setup easier, following the setup parameters.

tinySA:

Mode: LOW OUT

Level: -15dBm

Sweep span 150MHz

Sweep time 1.5s

DSO:

Utility: Page 2/3: Time set to actual time

Acquire: Mode: Peak

Display: Page 2/2, Grid Intensity: 15, Wave Intensity: 12

  • Measuring CH1 (CH2 probe on tinySA HIGH)

    • CH1 Frequency response: probe: 1:1 50 Ohm load, 20mV/div, DC
    • CH2 Trigger: 10:1, 2V/div, DC
    • Horizontal: 80ms/div->Menu: Page2/2 Time/Div: Fine: adjust SEC/DIV to 100ms/div

    • Trigger: Edge, CH2, Rising, Mode: Normal, DC, 1V
  • Measuring CH2 (CH1 probe on tinySA HIGH)

    • CH1 Trigger: 10:1, 2V/div, DC
    • CH2 Frequency response: probe: 1:1 50 Ohm, 20mV/div, DC
    • Horizontal: 80ms/div->Menu: Page2/2 Time/Div: Fine: adjust SEC/DIV to 100ms/div

    • Trigger: Edge, CH1, Rising, Mode: Normal, DC, 1V

-- RudolfReuter 2021-02-24 16:13:29


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TinySA-ScanLowSynch (last edited 2021-03-01 16:16:02 by RudolfReuter)