[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Discuss-gnuradio] ( An attempt ) to run GNURadio on WinTV : )

From: Hew How Chee
Subject: Re: [Discuss-gnuradio] ( An attempt ) to run GNURadio on WinTV : )
Date: Sun, 28 Jan 2007 00:51:54 -0800 (PST)

Hi Jim,
Can't remember that clearly, but the idea is to get the 2nd sound IF of the TV/FM tuner capacitively to one of the ADC inputs. The IF pin is one of the TV/FM tuner output pin. (It might not be available in all tuner module). I removed the existing circuit that was attached to this IF pin, in my case, I just need to removed a 0 ohm resistor. I also resisitively divide the IF pin output voltage just enough so that it does not exceed CX23881 voltage level. This step might be redundant since I do not have a oscilloscope to measure the IF pin voltage swing.
The sine came from a program written for Palm Pilot. Looking back at the code, I guess its about 2k. You can inject the tone direct to the composite video in and use the CX built in multiplexer to select this input.

Jim Perkins <address@hidden> wrote:
Do you recall what the hardware mods were?  I'm wondering if  I can clean up card with caps here and there.  I looked at your sine wave data.  I low pass filtered it and got rid of most of that garbage.  The tone is at 1890 Hz as far as I can tell.  How did you generate that tone and what was the center frequency?  Where did you inject the tone?

Hew How Chee wrote:
Hi Jim,

The card I use last time is PV-TV304P+ (REV .2B) with FMRC (FM and Remote Control) . The chipset used is CX23881. The card from newegg.com is using CX23883. Can't tell it is compatible or not. The data I got is 8 bit unsigned. Didn't try out 10 bit since I was quite dissapointed by the noise in the 8 bit digitized signal. Nevertheless, it is still possbile to digitize the 10.7 MHz FM IF with hardware mods.

Note that the source code at http://www.geocities.com/how_chee/cx23881.htm can't compile and run in Linux kernel 2.6 and is not hooked up to GNURadio. It was developed using Knoppix Live CD 3.4 running kernel 2.4.x.

Best regards,

Expecting? Get great news right away with email Auto-Check.
Try the Yahoo! Mail Beta.
reply via email to

[Prev in Thread] Current Thread [Next in Thread]