Update on yesterday’s blog

I finished the case but on test found that the SMPSU was providing far too much noise on the 25MHz reference output, so I have decided to change out the SMPSU for a linear one rather than try to filter the big one. That will mean a external PSU again, but will free some room in the case for some extra parts, to be decided.

I also found a problem with the LNB PSU to RSPPro2 (crimped) power connector lead into the bias tee. I’ve never seen this PowerPole intermittent problem previously, but will ensure I look for it next time!

A further update

I found that the original SMPSU, that fitted into the rear of this case, was completely RF quiet and spike free. In preference to using an external linear PSU I have grafted this SMPSU back into the case and am using it to power the reference OCXO/multiplier reference. Since  this PSU  is  rated at 50W (with small fan) I am going to try and use it to power the transverter as well, even though the overall 12V rating is marginal. As long as the OCXO is warmed up the total current draw is just about manageable. As the 5v/8A output is not being used, and neither is the slightly lower current rated SB 12v output, then the main 12V output should be comfortable at or slightly beyond that 12v output rating.  We’ll see what happen!

Sam