55987RE: [softrock40] Re: DC-DC converter for Ensemble RX II
- Jun 6, 2011
Just for reference: I’ve run my softrocks with 9V DC power for a long time without any noticeable negative effects but I’ll admit that I’ve not pushed them to the limit on transmit.
Alan – W6ARH
Probably a good point in general. 12 VDC isn't particularly magic. However it does potentially give a bit more headroom before distortion in the OpAmps. I'm surprised that they aren't run from it instead of the 5 VDC of the SR Ensemble RX design. Maybe I've missed something obvious though.
Also, I don't know that there is a linear correlation between output voltage on the switching regulator and overall efficiency. At least, I'd suspect for very low outputs, even with all else equal (which it never is!) that diode drop in the switcher would begun to hurt.
Still, if someone is looking for alternative ways of powering a SoftRock/Si570 combination there's no requirement to provide 12V.
I think the most useful thing I found is that switching regulator hash needn't be a severe problem. I suspect that the switched capacitor DC-DC converter solutions - which generally are limited to 2x voltage- might work just as well as the inductive switcher I used.
I'd say the good news is that it isn't difficult to combine existing SR hardware/synthesizers to make a small, portable, all-mode, general coverage receiver that has decent performance very inexpensively.
> OK, time for me to expose my ignorance again... Why insist on 12V output?
- << Previous post in topic