Re: Troubleshooting Softrock lite RX - FIXED!!
- Hi Tony
Thanks - that's Christmas sorted then!
--- In email@example.com, "Tony Parks" <kb9yig@...> wrote:
> Hi Norman,
> I have 100 pices of the CMOS Si570 due in later this week or early
next week. Your October 8 order would put you in the group to
receive one of the Si570 devices to be mailed next Monday or Tuesday.
> Glad to hear the I and Q signals now look right with the AC gain
about right from antenna input to audio output.
> Tony KB9YIG
> ----- Original Message -----
> From: norman.billingham
> To: firstname.lastname@example.org
> Sent: Wednesday, December 03, 2008 1:20 PM
> Subject: [softrock40] Re: Troubleshooting Softrock lite RX -
> Hi Tony
> Checka all capacitor and rseitance values this afternoon and all
> seemed OK. Despite having inspected everything under 10X
> magnifcation and found no problems, I decided before yanking
> components to flux everything around the mixer and op amps and
> up every joint with a hot iron and it came to life - must have
> joint that was OK for DC but not AC as all voltages were OK.
> It's sitting on the bench putting out about 1.6V of I and Q from
> about 40mV RF in.
> Anyway - thanks again for all the help.
> Any news on when I'm likely to get the Si570 for my V9 kit?
> on October 8
> 73 Norman
> --- In email@example.com, "Tony Parks" <kb9yig@> wrote:
> > Hi Norman,
> > With DC gain of each op-amp about right, it seems that R9 has a
> larger resistance than 10 ohms, or C14 has more capacitance than
> pF, or there is an AC load on the pin 1 output of U5. (Also still
> the possibility there is a problem with U5.) I would suggest
> removing C16 first to see if the AC voltage at pin 1 of U5
> with the RF test signal input you are using. Next, remove C14.
> > 73,
> > Tony KB9YIG