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Products => Test Equipment => Topic started by: ab#FFFF on October 30, 2020, 02:23:37 pm

Title: weird issue with UNI-T UTG962
Post by: ab#FFFF on October 30, 2020, 02:23:37 pm

Hi All,

I while ago I brough an UNI-T UTG962 signal generator (from UNI-T aliexpress store). It works but I have a weird issue: on channel 2 I have to set the double value on amplitude in order to get the required output. For example if I need 5Vpp I have to set 10Vp; this happened for any wave forms, any amplitude at any load impedance. Channel 1 works well.

I've contacted the company and waiting for their feedback.
Meanwhile I'll be very glad to hear your input on how to fix this issue.

Thanks and Most Appreciated,
Best Regards,
#ab

Title: Re: weird issue with UNI-T UTG962
Post by: Mechatrommer on October 30, 2020, 07:56:17 pm

1) is your scope attenuation setting at 1X?
2) do you put 50 ohm termination near DSO?
3) CH2 is HighZ on your UTG962?

Title: Re: weird issue with UNI-T UTG962
Post by: ab#FFFF on October 30, 2020, 09:00:50 pm

1. scope attenuation is 1x
2. DSO ia set to high Z impedance (1Mohm).
3. CH2 is HighZ on UTG962 (and there is no amplitude limit set).

Anyway, CH1 behave in normal way. If the amplitude is set to 5Vpp with an offset of 2.5V, on the scope I see a signal with 5Vpp amplitude and 2.5 offset.
On CH2 in other hand, I have to set the double value (10Vpp) in order to see 5V at the output. If I set 20Vpp on CH2 I see a 10Vpp signal on the scope... very consistent (is not limited by the output seen impedance). The major problem is: I cannot exceed 10Vpp output on CH2, on high impedance, because the amplitude setting is limited to 20Vpp.

thanks,
#ab

Title: Re: weird issue with UNI-T UTG962
Post by: ab#FFFF on October 30, 2020, 10:29:50 pm

I think that I figure out... The MODE (modulation was selected). I deselect-it for CH2 and now everything is fine. :)