ADALM-PLUTO (new DATV SDR)

Digital ATV - The latest generation, cutting edge ATV - Please discuss it all here.
Forum rules
This forum is run by the BATC (British Amateur Television Club), it is service made freely available to all interested parties, please do not abuse this privilege.

Thank you
radiogareth
Posts: 42
Joined: Wed Jan 06, 2016 9:46 am

Re: ADALM-PLUTO (new DATV SDR)

Post by radiogareth » Thu Aug 09, 2018 10:46 am

That would be nice. I can install stuff, but I can't write it at this sort of level.
I'm wondering if SDRangel (which recognises the Pluto) can be persuaded to TX FMATV or DATV. Undoubtedly powerful, its in need of an 'idiots guide' on how to use it, for me at least.
Food for thought.....

Gareth

darrenrainer
Posts: 2
Joined: Thu Aug 09, 2018 12:40 pm

Re: ADALM-PLUTO (new DATV SDR)

Post by darrenrainer » Thu Aug 09, 2018 1:20 pm

Hi all,

I am hoping to receive my ADALM Pluto in the post today. I would like to use it for ES'HAIL assuming everything goes ok on the launch. From what I understand the Pluto has 1mW output. What I am thinking of doing is getting the DB6NT MKU 2424 Upconverter which has a 144Mhz IF and 20W out at 13cms. If I put a suitable amplifer between the Pluto and Upconverter will this be any good ? Obviously more power is needed than the 20W but it is a start.I have a 1.2M dish for the 10GHz downlink which is currently picking up Arab TV at satellite at 26 deg east.

g0mjw
Posts: 500
Joined: Sat Sep 20, 2014 9:15 am

Re: ADALM-PLUTO (new DATV SDR)

Post by g0mjw » Thu Aug 09, 2018 7:37 pm

G8XZD-TV wrote:
Wed Aug 08, 2018 8:36 pm
MJW Why do you need a 4m up converter? If you have a Pluto you can program it to convert 4m to 23cm to feed into a minitiouner.

A how-to for CQ-TV maybe Mike?
It is fairly simple to set up a transponder in a package like Gnuradio (Linux, Windows only if you have to) or PothosSDR (easy to use Windows package) which will be fine for 4m over USB2. All you need to do is use it to set up a source and sink, connect them together, set the sample rate, frequencies and gain, maybe some filtering and run it. Crude but effective. This is with my Lime as my pluto is running its web server at the moment.
Capture.PNG
Capture.PNG (14.62 KiB) Viewed 298 times
For wider bandwidth better to do it on the device itself. I am not sure how to do that yet, but others have been doing interesting things. See plutoweb https://www.rtl-sdr.com/ for inspiration.

Maybe a better example.
Upconverter.jpg
Upconverter.jpg (798.63 KiB) Viewed 247 times
Last edited by g0mjw on Fri Aug 10, 2018 12:00 pm, edited 1 time in total.

M0NRD
Posts: 5
Joined: Thu Aug 10, 2017 6:22 pm

Re: ADALM-PLUTO (new DATV SDR)

Post by M0NRD » Fri Aug 10, 2018 7:37 am

Thanks for the info and pointers in this thread, got a Pluto a couple of weeks and have only just started dabbling. Hadn't even considered using it as an up/down converter but it is so obvious. Just got to sort out a decent linux setup, ones I have are on older PCs

Andrew M0NRD

darrenrainer
Posts: 2
Joined: Thu Aug 09, 2018 12:40 pm

Re: ADALM-PLUTO (new DATV SDR)

Post by darrenrainer » Fri Aug 10, 2018 11:53 am

g0mjw wrote:
Thu Aug 09, 2018 7:37 pm
G8XZD-TV wrote:
Wed Aug 08, 2018 8:36 pm
MJW Why do you need a 4m up converter? If you have a Pluto you can program it to convert 4m to 23cm to feed into a minitiouner.

A how-to for CQ-TV maybe Mike?
It is fairly simple to set up a transponder in a package like Gnuradio (Linux, Windows only if you have to) or PothosSDR (easy to use Windows package) which will be fine for 4m over USB2. All you need to do is use it to set up a source and sink, connect them together, set the sample rate, frequencies and gain, maybe some filtering and run it. Crude but effective. This is with my Lime as my pluto is running its web server at the moment.

Capture.PNG

For wider bandwidth better to do it on the device itself. I am not sure how to do that yet, but others have been doing interesting things. See plutoweb https://www.rtl-sdr.com/ for inspiration.
Thanks for the reply. The Up converter is for 13cms not 4M. I was thinking of using the 144mhz upconverter to 13cms as it has 20w output so would setup the Pluto to output at 144mhz. Alternatively I guess just generate the 13m on the Pluto and put an amplifiers on the output. There is alot to learn about configuring the Pluto so a guide would be good :-)

radiogareth
Posts: 42
Joined: Wed Jan 06, 2016 9:46 am

Re: ADALM-PLUTO (new DATV SDR)

Post by radiogareth » Sun Aug 12, 2018 6:40 pm

I have Pothos GUI installed and running on my PC. But I need to find a beginners 'how-to' to make any headway with it.

radiogareth
Posts: 42
Joined: Wed Jan 06, 2016 9:46 am

Re: ADALM-PLUTO (new DATV SDR)

Post by radiogareth » Mon Aug 13, 2018 4:58 pm

WOndering if one of these would suit the Pluto output? Plus some band specific filtering of course.....

eBay item (and lots similar) 172794764816

https://www.ebay.com/itm/1-930MHz-2W-RF ... 2794764816

Gareth

g0mjw
Posts: 500
Joined: Sat Sep 20, 2014 9:15 am

Re: ADALM-PLUTO (new DATV SDR)

Post by g0mjw » Mon Aug 13, 2018 9:02 pm

radiogareth wrote:
Mon Aug 13, 2018 4:58 pm
WOndering if one of these would suit the Pluto output? Plus some band specific filtering of course.....

eBay item (and lots similar) 172794764816

https://www.ebay.com/itm/1-930MHz-2W-RF ... 2794764816

Gareth
No, I don't think so. While a useful gain block, it won't give 2W at any reasonable linearity and 2W is not normally sufficient so you would need another amplifier. Two modamps in series is probably too much gain, 30dB+, the pluto would have to be well backed off and then it might be less clean. It would be better to just use one device to bring the power up to say 10-100mW and then a filtered band specific amplifier to follow. The RA modules need 5-10mW of drive which is a bit more than the Pluto can give but well below what this amplifier would deliver. Putting those in series might result in over 60dB of gain and oscillations. They are cheap enough though so perhaps you could bypass the driver if it has too much gain.

Mike

G4FRE
Posts: 38
Joined: Fri May 26, 2017 6:57 am

Re: ADALM-PLUTO (new DATV SDR)

Post by G4FRE » Tue Aug 14, 2018 6:56 am

Mine produces around 25mW when driven by pluto on 437MHz as observed on a S.A. My pluto shows -20dbm of DATV and -9dBm of carrier when controlled by express v1.25LP9. The output level doesnt get any better over the rest of the pluto frequency range. Pluto not reaching it's rated power is not an uncommon experience from what i read on the web

The amp does however do a good job when driven by portsdown, allowing my LDMOS amps to be driven

Dave
G4FRE

g0mjw
Posts: 500
Joined: Sat Sep 20, 2014 9:15 am

Re: ADALM-PLUTO (new DATV SDR)

Post by g0mjw » Tue Aug 14, 2018 1:28 pm

Interesting. It's supposed to produce a lot more power than that! What are the devices in that amplifier ? Surprised it's linear at a half watt or so needed to drive the LDMOS.

Post Reply

Return to “DATV - Digital ATV”