Hantek DSO2D15 FM modulation issue

[iw2evk]

Hi all,

The internal Signal generator on May Dso2D15 scope work fine in AM modulation but have a FM modulation issue.

When i choose a deviation less the 30 kHz the Signal it's not modulated.
Over +/- 30 khz work fine

This is a problemi during test of FM VHF UHF transceivers where the FM modulation it's max +/- 5khz.

Someone know a solution ?

i've contacted via mail hantek with no reply.

Thanks

Roberto

[Aldo22]

Why do you think the signal is not modulated?
I can't reproduce that here.

[iw2evk]

Hi,
with a 50cm wire place as antenna in bnc and a  transceiver near i can't hear the fm  +/- 5khz modulated signal from 1 khz tone.
If i setting +/- 75 khz deviation and hear with a standard home fm receiver i've a cristal clear note on speacker.
So i suppose a issue in low level modulation.
if you have a HF transceiver make yourself this test..

Note : 
for 88-108 Mhz setting are Fout 10,7 Mhz (i.f.) deviation +/- 75 khz tone modulation 1khz (heard Ok)

for transceiver Fout 24 Mhz deviation +/- 5khz tone modulation  1khz (no audio in transceiver)

[Aldo22]

Are you sure this has to do with the Hantek AWG?
I don't have an RF transceiver and don't know much about it.
I can only measure with the TinySA that the modulation is there.