for firmware update it seems by "DDS Signal PC Software "
So ...
my board are +5 feed only .. ; replaced switching to linear PSU +5V ; some LC filters on board already exist for opamp feeding
Can not solve noise output ; around 30-90 Mhz spectrum , about 8-9 mV P-P , seems opamp input picking noise from something ....
If I turn ON\OFF channel , relay clicking and noise changing from 18 mV to 7-8 mV P-P .....
Added OCXO --
I see changes for example 10.000000 kHz changes to 10.000001 kHz , on my Freq. counters , as counter limited to 8 digits. unfort. jitter not five for more precise count it. Btw , quite cool that frequency resolution are working well ...
I did OCXO adjustment in place by embedded counter , and 10Mhz GPS reference
Change potentiometers to multiturn ; did adjustments - DC offset in range of 20-50 microvolts, AC reflecting output , and seems symmetrical, and yes !!! P-P amplitude changing to 0.1 mV, multimeter shows changes in that resolution .....
an output circuit still didnt changed yet, need opamps , resistors ...
in overall:
negative:
noise .... not possible to use with amplitude lower then 30mV P-P , let say ; (unless some low pass filtr ... )
jutter - kinda.
phase shift between 2 channel - ( it can be adjusted by channel setting, but it soo silly mistake, and easy to compensate by software )
another silly stuff - frequency meter, having powerful FPGA and good MCU , just to build a primitive counter - it not a serious ....
positive:
precision some kind ...
it overall it acceptable , i think ....
i got for $90 60M , just in intention to replace my FY3200 as a daily gen usage thingi ..... and I would say , with mods replacement quite useful ... comparing the old FY3200 the new one a bit more handy to use.
someone's video to program custom waveform for frequency increasing, if you gen has a low limit
and that is all im able to do about noise drop ... generating SINE 1Mhz 5mv P-P
This is experiment with a pulse injection:
So I have 1.2kHz , about 0.5V amplitude , and duty 0.001% , not enough speed for risin \ fallin , but simulate some random noise injection ... seems acceptable
Finally, I do try to figure out about jitter measure as many do complains, I'm not certain how ... any advice?