Transmitter Software Capabilities and Issues (Jessie)

[G8GKQ]

Hi Rob

I think that your last update must have failed halfway through. What you need to do is create a file /home/pi/rpidatv/scripts/installed_version.txt and enter 201704060 in it and then save it. So, at the command prompt:

Code: Select all

nano /home/pi/rpidatv/scripts/installed_version.txt

then enter 201704060

then press control-x, y, enter

If you then go back to the menu (/home/pi/rpidatv/scripts/menu.sh menu) and try another update, you should be sorted.

Dave

[ZL3TCM]

Again many thanks it worked av treat no issues and all upgraded now

regards Rob ZL3TCM

[vk5bd]

Hello Dave,

Great work on this Portsdown Project.

I had some contact with Everiste through the RpiDATV project previously and then got distracted with other projects and only recently got back to working with the PI as an alternative to generating the DVB-S signal for access into our local ATV repeater, one of the issues we have here is that our repeater is setup to take a 5000kS signal at 1275MHz. I know the documentation talks about the 4000kS limit but generally works at 5000kS.
I have reasonably successfully used the IPTSIN option from vMix.
I decided to try the CAMMPEG-2 option but had poor results with not getting a consistent signal, so using the Troubleshooting for Advanced Users suggestion from https://wiki.batc.tv/Feeding_Video_to_P ... _from_vMix, I saw the Pi was constantly throwing an underflow error. The diagnostic information indicated that the calculated values for Bitrate TS 6911764 and Bitrate Video 5173823, which seemed lower than the rates (TS Rate 8501k and Video 6279k) I was using for IPTSIN from the PC.
I then edited the a.sh file and added a line to force BITRATE_VIDEO = 6279000 before the code goes into the FFMPEG script.
I was trying various values trying to rid the underflow when (I would like to say through great mathematical skills ) I inadvertently deleted one digit reducing the number to 690000 and was able to achieve a constant signal output of the Pi Camera and the Tone/Beep.
I found that if I keep the number below approx. 2500000 I don't get the underflow error. I really not sure of why this is so, the number is certainly a significant change to the calculated value for Bitrate_Video.
I hope this helps with some diagnostics

73
Bevan

[G8GKQ]

Thanks Bevan

Pleased to hear that it is working for you now. I do try to make sure that new releases work at over 5MS as a stress test!

I'll look into the underflow issue - interesting findings.

Dave, G8GKQ

[G8GKQ]

New Software Release

I've just issued a new release 201704160. This introduces a new start-up script. During start, the RPi now displays its IP address on the touchscreen; the boot-up time without a network is faster than previous releases. If a console menu is session is started while the touchscreen buttons are displayed, the touchscreen goes blank whilst control is exercised from the console. No need to use control-C any more. I have also added some extra messages in the Wifi set-up script and added the option to apply a forced update if the update script encounters an error.

Lastly, new builds are now baselined on the 2017-04-10 Jessie Lite release, which should reduce the time taken to produce a new SD Card.

Dave, G8GKQ

[vk5bd]

Hello Dave,
I downloaded your latest version and tested the CAMMPEG-2 source option and it seemed to be working fine, yet there had been no changes made to that part of the code. I then did some test transmissions to our local repeater, and the problem seemed to come back, I tried my code modification again and still no improvement in the number of underflows, then when I moved the camera back to where it was seeing a very still image the underflows went away. Even with my forcing of lower video bitrates very dynamic pictures cause the underflow error, so I think my first observations are not as valid as I first thought and that it was the imagery in front of the camera had a bigger impact on the underflow error than my code changes.
73
Bevan, VK5BD

[F5SWB Dimitri]

Hope it will help you

http://www.batc.org.uk/forum/viewtopic. ... 901#p12215

[G8GKQ]

Hi Bevan

I have just tested the latest release (201704160) with CAMMPEG2 at 5MS (and 6MS) and have had smooth pictures (and sound) throughout. I have not checked for internal underflow errors, but both MiniTioune and my domestic satellite receiver gave really smooth video with slow and fast moving images. The bitrates in CAMMPEG2 were optimised by Evariste and I haven't played with them.

I wonder if the receiver at your local repeater is perhaps a little critical of the input signal? How does the Portsdown signal look on other receivers?

Do you have any USB devices (or HDMI displays) plugged into the RPi that could be slowing it down?

Dave, G8GKQ

[g0uhy]

Hi Dave,

just updated to the latest software and screen just shows the BATC logo and the IP address. I've lost all of my original settings ie Tx freq, FEC, SR and touchscreen type. I've put everything back and it then boots up ok. Did I do something wrong or is there a bug which causes the original settings to be lost?

73

Malcolm G0UHY

[G8GKQ]

Hi Malcolm

There is a bug that very occasionally causes the loss of all the settings, but I have not been able to track it down yet. First time that I have heard of it happening during an update.

Did it ask you to reboot at the end of the update?

Dave, G8GKQ