My Knucker tuner is working.

Discussion about the Knucker DVB-T Tuner DVB-T Receive Software. See also https://wiki.batc.org.uk/Knucker
g3yjr
Posts: 82
Joined: Sat May 23, 2020 1:37 pm

Re: My Knucker tuner is working.

Post by g3yjr » Mon May 24, 2021 4:11 pm

That was good diagnosis Dave!

On re-inspecting the board, I found a solder hair between two pins that I had missed before. I removed it.

Using ITV 498MHz as a test signal I now get video decode, somewhat halting as expected, but no sound on PD4. I get video and sound via UDP into VLC.

It is useful to know that I can use ITV as a test signal. I don't know anyone locally who can send DVB-T to me.

I have a non-standard "3D Sound" USB sound card plugged in the RasPi (my standard card never arrived). Is there a line of code that I need to amend to get Knucker sound via PD4?

73 Graham

g3yjr
Posts: 82
Joined: Sat May 23, 2020 1:37 pm

Re: My Knucker tuner is working.

Post by g3yjr » Thu May 27, 2021 9:29 am

I can now decode DVB-T 500 kHz video and sound via QO100. I would be interested to know what frequency Knucker actually finds and locks on to. Is this displayed?

I've tried tuning to DVB-T 333 kHz signals from QO100, but the searches have so far failed. I don't know why.

My off-set is 500 kHz higher than standard in order to suit my Rocket LNB.

73 Graham
Last edited by g3yjr on Thu May 27, 2021 4:55 pm, edited 1 time in total.

radiogareth
Posts: 1211
Joined: Wed Jan 06, 2016 9:46 am

Re: My Knucker tuner is working.

Post by radiogareth » Thu May 27, 2021 9:59 am

Most of the signals on QO-100 are DVBS-2, Not DVB-T. There are occasional test signals which are generally next to the beacon as per the band plan.
Other than basic tests, DVB-T is for between tow of us earth-bound ops......
Gareth

g3yjr
Posts: 82
Joined: Sat May 23, 2020 1:37 pm

Re: My Knucker tuner is working.

Post by g3yjr » Thu May 27, 2021 4:48 pm

Gareth,

Perhaps I needed to say, I am referring to signals which the transmitting people have specifically told me are DVB-T signals. When they changed from 333 to 500 kHz, Knucker then found them. I've amended my post above to try to make it clearer. Poll PA3BYV was one person who provided a test signal. Frank DD0CW and Denis SR8RV also helped.

73 Graham
Last edited by g3yjr on Thu May 27, 2021 5:00 pm, edited 2 times in total.

G8GKQ
Site Admin
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Re: My Knucker tuner is working.

Post by G8GKQ » Thu May 27, 2021 4:55 pm

Hi Graham

The first thing that I would check is the tuning (calculation using LO offset). It may be close enough to work on 500 kHz, but not on 333?

Dave

g0mjw
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Joined: Sat Sep 20, 2014 9:15 am

Re: My Knucker tuner is working.

Post by g0mjw » Thu May 27, 2021 4:55 pm

I hope you were not trying to receive me as I was testing the Pluto DVB-T and it wasn't working. F4HSL was also sending 333KHz but successfully. I tried 500kHz which looked better but still not OK.

Mike

g3yjr
Posts: 82
Joined: Sat May 23, 2020 1:37 pm

Re: My Knucker tuner is working.

Post by g3yjr » Thu May 27, 2021 5:07 pm

G8GKQ wrote:
Thu May 27, 2021 4:55 pm
Hi Graham

The first thing that I would check is the tuning (calculation using LO offset). It may be close enough to work on 500 kHz, but not on 333?

Dave
Dave,

yes I'm thinking along the same lines. That is why I'm interested in knowing what frequency Knucker actually locks to when its search is successful. The LNB does drift a bit and is about 500 kHz high (off-set 9750.5 MHz), but I don't have any problem with DVB-S/S2 and MiniTiouner2 at 333, 250 or 125 kHz fed from the same LNB.

73 Graham

g3yjr
Posts: 82
Joined: Sat May 23, 2020 1:37 pm

Re: My Knucker tuner is working.

Post by g3yjr » Sat Jun 05, 2021 4:42 pm

g0mjw wrote:
Thu May 27, 2021 4:55 pm
I hope you were not trying to receive me as I was testing the Pluto DVB-T and it wasn't working. F4HSL was also sending 333KHz but successfully. I tried 500kHz which looked better but still not OK.

Mike
No I didn't try with your signal Mike. I did see it on Goonhilly though.

73 Graham

g3yjr
Posts: 82
Joined: Sat May 23, 2020 1:37 pm

Re: My Knucker tuner is working.

Post by g3yjr » Sun Jun 06, 2021 5:13 pm

Dave,

I resolved Frank's and Denis's DVB=T 250 kHz signals today, so that looks promising.

I will try again with 333 kHz when I get the chance.

73 Graham

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