Synchronise DDS function generator with SYNC signal created in Labview

[Mitss]

Lately, I am trying to built a high frequency lock in amplifier from scratch. For this a one channel ADC (16bit, 10MSPS) as well as a DDS function generator which can provide the requested frequency is used.

The problem is that because the DAQ card has only one channel I cannot provide simultaneously the actual signal as well as the SYNC (square waveform with same frequency and phase with the actual signal). Thus, lock in vi cannot work. In order to circumvent the problem I create the SYNC in labview however as you might guess the signal are not synchronised (created by different clocks).

Attached you find the vi I am using (Alpha.vi) where the signals I am talking about are indicated by A and B.

Any suggestion, please?

[Mathieu_T]

Hi Mitss,

It depends on which DAQ card you use, it might be possible to provide an external clock in order to synchronise your signals.

Also, some parts are missing in your Alpha.vi, furthermore could you show me where the B signal is ?

Thanks for you reply.

[Mitss]

Mathieu,

Could you please tell me more or give me a link about the usage of an external clock? The signal B (as well as the A) is noted with the corresponding letter.

Regards,

Mitss