Re: DDS Module is not functioning


Glad it's working!
Was that trace on the bottom side of the PHSNA that grounds D2 actually cut, or was it a board defect?
That amplitude behavior is not normal, in particular the big dip at 11 MHz. There is generally just a slow drop of 4 or 5 dBm over the whole range, sometimes a little 2 or 3 dB peak about two thirds of the way through the range. The counter port is just a resistor isolated tap ahead of the last attenuator... so check those attenuator resistors R12-14. The counter port is intended to be connected to a hi-Z load - but R19 isolates it so as to not mess up the load on the MMIC.
The J1 jumper (top left) grounds D2 for serial mode. It shouldn'r be needed since the PHSNA board grounds D2, but no harm done to leave it in place.
The J2 jumper  (top right) connects the comparator reference voltage (minus side) It really only matters when the square wave outputs are used, but it is normally installed.
The J3 jumper (bottom left) should be installed unless you decide to use a different resistor or voltage on the V-adj line
The J4 jumper is actually not a jumper so much as an connection to the other sinewave output (inverse phase) There's normally not a jumper installed there since it would short the inverted output to ground. If you wnated to use  both outputs the way the Type II PHSNA does, then the inverted output would be taken from J4.
I can see the messages all the way back to the beginning... you can sort by date either direction, and also navigate to a specific message. and you can search by content.  I have only deleted old "housekeeping" type messages from the group.
Jim, N5IB

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