To see if there is frequency drift effect from RF source, I tried to use DDS. I took DDS3 CH0 for the time being.

1. I removed 12dB attenuator connected to the output of DDS3 CH0.

2. I put 8dB attenuator (2*3+2).

3. Amplify with 13.6dB.

4. Goes to the amplifier which was used for old AOM RF source.

The frequency in DDS3 was found to be 109.541930MHz to make IR TEM00 on resonance.