ADSB receiver dongle

[Smaragd]

I'm on my third ADSB Receiver Dongle - the Mini USB DVB-T RTL-SDR Realtek RTL2832U on the Known Good Hardware list. On the first the aerial connector came loose, the second just stopped working. Has anyone else has problems and is there a more robust solution?

[Wadoadi]

I have just put my PilotAware together and was about to ask if it's normal for the MCX plug on the ADSB to get so hot you can't touch it!

In the past I have used the bigger USB TV adapters and not noticed the heat, maybe it only an issue on the smaller "recommended" ones.

Maybe your/the problem is heat related!?

[exfirepro]

Hi guys,

It is fairly 'normal' for the DVBT receiver dongle to run pretty hot, though not normally so hot that you can't touch the plug, but being metal, it will of course act as a 'heat sink' and absorb any heat generated by the board. The high heat level caused quite a lot of concern in the early days but very few failures. I know Paul Sengupta has changed over from an MCX plug to a solder mount SMA connector (the same as used for the P3i antenna), which being a screw connector is not susceptible to coming loose and pulling out as can happen with the MRX. Means you also need to change the corresponding plug on your 1090MHz antenna (not particularly easy) or buy an alternative 1090MHz antenna with a matching SMA connector of course.

Regards

Peter

[Mig29fuk]

I place my ADS-B Dongle away from RPi using USB Male/Female shortish cable, about 20 cm. It radically reduced the heating against when connected directly to RPi.
All three Units I produced are wired this way and all seems good.

G-RVBC, an RV6 hopefully will be transiting from Bath, Somerset to Newcastle on Saturday with ETD about 08.30 Local. It will be carrying Pilot Aware but is also Mode S with ES equipped.
A return flight will be late afternoon. Hope it gets spotted but not too close!

Regards
Gerry

[Paul_Sengupta]

I know Paul Sengupta has changed over from an MRX plug to a solder mount SMA connector

What prompted me to do it was that I used an MCX-SMA adaptor and it managed to push the centre pin of the MCX so it came loose from the PCB, taking the track with it. I thought rather than fix the MCX connector, I'd put in an SMA instead. It works very well, but screwing an antenna to it, the antenna plug also becomes very hot. My next bit of experimentation will probably be to find some sort of heatsink I can put on the R820T tuner chip, which is the thing which gets hot.

I have a bit of a collection of these R820T things of various sizes and various connectors.

I've even got one of the mini ones (looks the same) with an E4000 tuner chip in it. It's pretty crap at ADS-B!

[Smaragd]

Thanks to all for the advice. I now also have some bits I can play with!

[jamespratt]

I am also on my second (maybe heading for third?) DVB-T dongle - in the first one the copper antenna wire inside the dongle broke where it goes into the circuit board, the second one has a dodgey connection as well. Quality control/robustness is not great and the dongle and antenna connection are fairly exposed.

Any good alternatives short of rewiring the connector?

[Paul_Sengupta]

I've kept using a mini dongle myself as I've put an SMA connector on it, but I also have these sort of things for other SDR work:

http://www.ebay.co.uk/itm/RTL2832U-R820T-DVB-T-RTL-SDR-DAB-FM-USB-2-0-Digital-TV-Receiver-Stick-Tuner-CD-/281561364981?hash=item418e5d79f5:g:j3EAAOSw-W5UtH6t

It has a large TV style antenna connector on it which shouldn't break.

You can also get "premium" R820T dongles with SMA connectors. They're normally used for other SDR (Software Defined Receiver) work, but I don't see why they won't work with a PilotAware.

http://www.ebay.co.uk/sch/i.html?_odkw=r820t+sm&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xr820t+sma.TRS0&_nkw=r820t+sma&_sacat=0

[exfirepro]

I've kept using a mini dongle myself as I've put an SMA connector on it, but I also have these sort of things for other SDR work.......

.......You can also get "premium" R820T dongles with SMA connectors. They're normally used for other SDR (Software Defined Receiver) work, but I don't see why they won't work with a PilotAware.

http://www.ebay.co.uk/sch/i.html?_odkw=r820t+sm&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xr820t+sma.TRS0&_nkw=r820t+sma&_sacat=0

This one looks interesting Paul. Narrow metal case and clearance to adjacent dongle should help heat dissipation (one picture shows 2 side by side in a Pi - which we certainly can't do with ours) though these do look a bit 'thicker' height wise, so might possibly obstruct ports in the 'top' (or bottom) row. It is reported to use an R820T2 chipset. If Lee can confirm whether this is compatible it might be worth buying one to try. I certainly agree that SMA connectors are stronger and likely to prove more reliable in the long term than MCX.

Regards

Peter

[Smaragd]

Thanks Paul; I've now repaired one dongle where the MCX had come away from the board - can't see such a fault with the other, though. However now I've got the kit working satisfactorily in the aircraft I should be disturbing it less so hope not to have further problems. Your alternatives are noted as backup.

[Sean McDonald]

Any news on the compatibility of this one quoted here?

I've kept using a mini dongle myself as I've put an SMA connector on it, but I also have these sort of things for other SDR work.......

.......You can also get "premium" R820T dongles with SMA connectors. They're normally used for other SDR (Software Defined Receiver) work, but I don't see why they won't work with a PilotAware.

http://www.ebay.co.uk/sch/i.html?_odkw=r820t+sm&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xr820t+sma.TRS0&_nkw=r820t+sma&_sacat=0]http://www.ebay.co.uk/sch/i.html?_odkw=r820t+sm&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xr820t+sma.TRS0&_nkw=r820t+sma&_sacat=0[/b]

This one looks interesting Paul. Narrow metal case and clearance to adjacent dongle should help heat dissipation (one picture shows 2 side by side in a Pi - which we certainly can't do with ours) though these do look a bit 'thicker' height wise, so might possibly obstruct ports in the 'top' (or bottom) row. It is reported to use an R820T2 chipset. If Lee can confirm whether this is compatible it might be worth buying one to try. I certainly agree that SMA connectors are stronger and likely to prove more reliable in the long term than MCX.

Regards

Peter

[Paul_Sengupta]

Buy one and try it. Don't see why it shouldn't work. 

[Sean McDonald]

Probably will! I'm assuming you techies know what definitely won't work!

Buy one and try it. Don't see why it shouldn't work. 

[brinzlee]

I ordered one last week for another project.....It's in transit with UPS.....I'll let you know if it works with PAW when it arrives.....Certainly looks well made and hopefully will address the issues of porting some of that heat away from its main chipset.

[Paul_Sengupta]

Probably will! I'm assuming you techies know what definitely won't work!

Yes, TV dongles with something other than the R2832U interface chip won't work. Most tuner chips will work to some degree, though I've personally got one with an E4000 which is fairly deaf at ADS-B frequencies, but it does work, just (it's good for higher frequencies than the R820T though, so has its uses). Anything with the R2832U interface chip and the R820T tuner chip should work ok, including the new (as the above linked unit uses) R820T2 chip which is more sensitive.