On Tue, Nov 5, 2019 at 08:07 AM, Bob Macklin wrote:
NorCal40
As the NorCal 40 uses the SA602/612 GC mixer, the 49er DDS should work just fine.?
That said, the SA602/612, unlike many of the mini-circuit mixers (SBL-1 types), is not a 7dBm device, which again, is why the AD9850 DDS from the 49er (W8TEE) works well with that device.? The W8TEE DDS used in the 49er project, has an output level adjustment for tweaking.
If using a si5351 DDS, which has more than double the output level of the AD9850, it would be a good idea to pad (attenuator) down the output level down to something more palatable to the SA602/612.? Additionally, and this is just personal experience, putting some level of pad between the DDS and the mixer input lets both devices see a solid 50 ohm impedance which, is a good thing.
Robin - AC7LX
