Cannot import name tv_rx

GNU Radio
1

I just got myself a TV_RX, and it works fine with the examples like
usrp_wfm_rcv, but when I run any of the tvrx specific examples
(particularly of interest is tvrx_tv_rcv.py), I get the following
python error
ImportError: cannot import name tv_rx

I tried changing it to db_tv_rx (as thats what I saw in the
site-packages directory), but it spit out a bunch of errors about no
global name tv_rx. What’s going on here? did I somehow not get the
tv_rx package when I should have?

2

On Tue, Apr 25, 2006 at 10:08:09AM -0700, Erik T. wrote:

I just got myself a TV_RX, and it works fine with the examples like
usrp_wfm_rcv, but when I run any of the tvrx specific examples
(particularly of interest is tvrx_tv_rcv.py), I get the following
python error
ImportError: cannot import name tv_rx

I tried changing it to db_tv_rx (as thats what I saw in the
site-packages directory), but it spit out a bunch of errors about no
global name tv_rx. What’s going on here? did I somehow not get the
tv_rx package when I should have?

Don’t use that example. It’s out out date, but still left in there
because it contains some code that was useful for experimenting with
TV signals.

[Martin, can you please update or remove that example? Thanks.]

What are you trying to do? Most of the examples use the
general-purpose daughterboard handling code and will work
with any daughterboard.

Eric

3

I’m trying to see if I can get any off-air TV signals - FM radio
reception works pretty well, so that seems like the next step…

4

On Tue, Apr 25, 2006 at 11:19:15AM -0700, Erik T. wrote:

I’m trying to see if I can get any off-air TV signals - FM radio
reception works pretty well, so that seems like the next step…

usrp_rx_cfile.py will allow you to grab them and log them to disk.
It works with any daughterboard.

Eric

5

Eric B. wrote:

[Martin, can you please update or remove that example? Thanks.]
I removed the old broken tvrx_tv_rcv.py example and added new working
examples.
usrp_tv_rcv.py and usrp_tv_rcp_nogui.py

They work out of the box when you use realtime capturing and processing,
but then you need a high decimation factor (for my PC 64 or higher)
This means you get a much lower horizontal resolution then you want (you
really want decimation 4 or 8)

They can output to a file, so you can view it with imagemagick.
They can also output to a realtime sdl video window.
For this you need to build and install gr-video-sdl
(This is only in cvs and not yet in a tarball)
There is no synchronisation yet. I am still working on the sync blocks
but they still don’t work reliably.
Also note that when you want to receive a Tv channel that the
video-carrier is not at the centre of the channel.

When you want to first capture to file, you need a decent way of
capturing to interleaved shorts.
(usrp_rx_file.py is a bit outdated)
I made an updated version of usrp_rx_cfile.py which can also output
interleaved shorts.
(It can also do 8 bit transfers and automatically disables halfband when
you use decimation < 8)
I attached a diff for usrp_rx_cfile.py to add these features to this
mail.
(Eric, if you like it, I can apply it to cvs)

If this new usrp_rx_cfile.py works fine, we should probably remove
usrp_rx_file.py.

greetings,
Martin

6

On Wed, Apr 26, 2006 at 04:53:29AM +0200, Martin D. wrote:

Eric B. wrote:

[Martin, can you please update or remove that example? Thanks.]
I removed the old broken tvrx_tv_rcv.py example and added new working examples.
usrp_tv_rcv.py and usrp_tv_rcp_nogui.py

Thanks!

When you want to first capture to file, you need a decent way of capturing to interleaved shorts.
(usrp_rx_file.py is a bit outdated)
I made an updated version of usrp_rx_cfile.py which can also output interleaved shorts.
(It can also do 8 bit transfers and automatically disables halfband when you use decimation < 8)
I attached a diff for usrp_rx_cfile.py to add these features to this mail.
(Eric, if you like it, I can apply it to cvs)

If this new usrp_rx_cfile.py works fine, we should probably remove usrp_rx_file.py.

Please apply the patch and remove usrp_rx_file.py

Thanks,
Eric