Having RF interference on 150MHz and 400MHz traced to DAQPad-1200

[b1ll]

none

[RIO-Todd]

So you think the DAQPad-1200 is generating the 150MHz and 400MHz signals? How have you determined this?

This just seems kind of odd because I don't think the DAQPad-1200 could even generate a signal within the RF frequency range (the only possibility would be noise but I've never heard of anything similar).

I would suggest to make sure you shield the cable and connector block used with the DAQPad-1200 to help out with this coupling.

I hope this helps.

Regards,

Todd D.
NI Applications Engineer

[b1ll]

Thank you for your response.
I used a hand held monitor receiver to pick up the 150 MHz. signal from over 100 feet away. The signal brought the receiver to full quieting when the DAQPad-1200 was turned on (without any connections except for power), and went to full noise when the DAQPad-1200 was turned off.
The DAQPad-1200 is used with an RF system to process weak signals, <-130 DBm.
I have tried shielding but with no great success, and wanted to know if the DAQPads' 10.0000 MHz. RF oscillator could be changed to another frequency to avoid problems. I only need to have 150 and 400 clear.

Best Regards
Bill

[RIO-Todd]

Hey Bill,

Unfortunately, it isn't possible to alter the 10 MHz oscillator of the DAQPad-1200. Some of our newer devices that have a RTSI connection can be configured to use an external timebase, but doing that just drives everything off of another timebase frequency. It doesn't actually change the frequency of the onboard oscillator.

Regards,

Todd