Re: [softrock40] Re: Soundcard, spectrum bumps, etc
- --- Terry <wb4jfi@...> wrote:
> --- In firstname.lastname@example.org, "xeloradio" <sealions@...>Maybe this is obvious, but I have not heard it mentioned in a while
> > The recent discussion on ground loops, etc is of interest since I
> > using a softrock on the IF of an ICOM PCR 1500 which works fine
> > one room but not in another. There is either a huge central bump
> > outright oscillation. The cable layout is slightly different.
> > I tried a variety of soundcards about a year ago and one issue
> > that anything based on the TI 2900 chip for USB has one channel
> > shifted and would not work with some software such as Rocky. I
> > not tried it lately.
> > A do-it yourself sound card in Nuts-n-Volts equivalent to a kit
> > Belgium and probably a few other cards used this 2900 chip, and I
> > no luck with it.
> > I put a list of soundcards I tried onto my web site.
> > http://www.aero-arts.com
> > Dave
> > K0IMH
> I too played with the N&V PCM2900 board. At first, it was VERY
> disappointing. But, someone sent a message here about there being
> error on the PC board, with suggested changes. I made those
> and the board now works much better. It's still a compromise, and
> doesn't work nearly as well as the Audigy 2 ZS PCMCIA card. But,
> is actually OK, especially for the cost.
> Search for message 13357 in this group for the fix to the board.
> Regarding the one sample delay, Rocky (and PowerSDR, an others) has
> an adjustment for that. The afore-mentioned Audigy PCMCIA card,
> other SB cards also require the same adjustment. No big deal.
so newbies may have missed it. First start up Rocky without anything
connected. If there are those bumps and stuff, no amount of work on
grounding of inputs/outputs of the softrock (since it is not
connected) is going to fix this. You will need to find up a way to
clean up the PC. Sometimes you can do a direct connection to the
sound card rather than going into the jacks on the front or back of