Where next~? (Hardware upgrades)


#1

Morning all,

I have what I think is a pretty sweet station

oPi running ADSB-Receiver.net image (Incl piAware and Mut)
fA antenna
fA filter
HAB amp
LR400 coax

… but i;m still using the original RTL USB stick.

Getting pretty decent range, c280 - 300 nm - good coverage etc.

Have seen some of the well-known branded reciever “boxes” (cant remember names off hand!)…

What would be a recommended “next step” upgrade to the USB reciever itself, and why?

Not wanting to spend mega-bucks, maybe up to £100 at this point…

Looking for recommendations and “pitches” of what such an upgrade would give?

Ta :slight_smile:


#2

HAB amp https://store.uputronics.com/index.php?route=product/product&product_id=50 ?

overall noise figure of the unit to 0.75dB
PSA4-5043+ Ultra Low Noise Figure, 0.75 dB

For LNA important parameter is Noise Figure.

PGA-103+ : Low Noise Figure, 0.6 at 1 GHz; 0.9 dB at 2 GHz
SPF-5189Z : Noise Figure 0.55 dB at 0.9 GHz
MGA-82563 : Noise Figure 2.10 dB at 1.0 GHz

Another option is to extremely shorten the length of the cable and place the receiver near the antenna.




#3

The only things I can think of, under the available budget, are:

  1. Replace the generic dongle with an FA Pro Stick +. Gain settings may need adjustments;
  2. Or an RTL-SDR Blog v3 dongle. Better shielding and other improvements;
  3. Increase the height of the antenna (you didn’t say how high it currently is).

But frankly, with that kind of range, I would be happier than a pig in a garbage dump.:rofl:


#4

Not clear if you are looking for more range, more coverage or more planes. 280-300nm is pretty good for range, you might want to check on what your horizon “should” be, using the heywhatsthat website.


#5

I agree with @skip20092017
I have a radarcape (~$US700) with a DPD antenna, cavity filter, uputronics amp and LMR400. I only get to 200NM as I am only 30ft(10M) AMSL. I get 1600msg/sec so am probably close to the limit.

If you have a lot of electrical noise in the area(I have a dozen cell towers) you could try a better filter. I need to use both the uputronics amp/filter and a cavity filter in my location. The radarcape has a huge dynamic range so can easily cope with it.
The V3 rtl-sdr is better than the first gen. It also works well with a bias-t powered amp.
V3 specs https://www.rtl-sdr.com/wp-content/uploads/2018/02/RTL-SDR-Blog-V3-Datasheet.pdf
The latest FA dongle is also great.

Have you look at optimsing the gain setting. This can help a lot of people. abcd567 and others have done a lot of work on this.
Shielding the dongle also helps me. I bought some metal cases for my FA dongles(I have several setups).
(You can also use the case from an old rtl-sdr dongle on an FA dongle)

Putting the RPI in a metal case can protect the dongle from the electrical noise it makes.
Even putting RF chokes on the usb power lead and USB pigtail for the dongle(if you use one) can help with noise.

There is a user near you that gets a lot more traffic. They get more range to the south. You get a lot more to the North.


They could just be in a better location (usually higher) to see more traffic. Maybe check with them to see how they are setup.


#6

Thanks for the replies gents :slight_smile:

For me, I’m most interested in range - I love the novelty of being able to see up to x miles! :slight_smile:

Although i did adjust the gain etc, using guides from Obj and our local guru’s, I though I’d “push it to the max” and set the gain to the highest numerical value, certainly seems to have increased my stats - both in terms of range and contacts.

I’ll let that bed in for another week or so, and see how it looks…


#7

Re RF Chokes…

These sound a good idea.

From what I read, it’s recommended to put one on either end of the usb lead/s, as you’re “not sure which device is creating the noise”.

Makes sense - is there any down side to adding two RF chokes to a single USB cable, one either end?


#8

K - toying with the idea of the RTL-SDR V3.

However, the details review here (http://www.radioforeveryone.com/p/group-ads-b-test-19-dongles.html) rates the fA Pro stick as being even better, due to its onboard LNA.

  • As I already have the HabAmp, would the RTL-SDR with the HAB Amp be better than the fA Pro stick?
  • If I got the fa Pro stick, would I leave the HAB amp in too, or take it out (too much amplification?)

#9

Not at all. It’s the best way.


#10

This is why I suggested the RTL-SDR Blog dongle, you already have an amp. As for being better than the Pro Stick, it’ll depend on the specs of the amp.

Try with the amp in the circuit, but the gain level in the dongle would likely have to be reduced. I prefer to not max out on gain settings, so reducing the gain in the dongle, if you keep the amp, is actually good.


#11

Thanks for the advice @dxista - I’ll have a look this evening! :slight_smile:


#12

Hi guys, quick update.

Have added the V3 dongle, have also removed the “metal cage” from the female end of the USB extension to reduce noise, so now looking at RF chokes.

From what I’ve learnt recently, I’m thinking of the clip on chokes, one either end of the cable/s…

Couple of questions:

  1. Choke sizes
    Lets say my “target cable” is 5mm diameter.
    Am I best getting a 5mm choke, and literally just clipping it on, OR get a 10mm choke, then loop the cable through it 4 times? (i’ve seen people put 4 chokes on, one after the other. I’ve also seen people wrap the cable through, with 4 x being common).

  2. Which cables?
    I have power, data (usb) and data (rj45/network) running my station.
    Which cables should I put chokes on - I’m guessing “all of them”?


#13

I think that’s what I need - something whit better dynamic range than the 8 bit of the tuners that I have now: FlightAware Pro Stick, FlightAware Pro Stick Plus and one of the generic (R820T2) blue dongles.
I have a flow of planes flying almost above my head. The strong close-up signals limit the reception of the far ones, especially when there are a lot of them.


#14

@SoNic67,

Give the airspy mini a try first. It also needs an amp but is about $US100. It sucks a lot of CPU. I run mine on an odroid XU4 (8ish CPUs). Can simply power an amp using bias-t with a single command line change.

https://v3.airspy.us/product/a-airspy-mini/


#15

I might. I wonder - will it run in decimation mode on the Pi3? I don’t think I am ready to shell another $90 on a Odroid XU4 yet.


#16

Give it a try. I think I started on an RPI2 or maybe a 3. The 3+ does have a little more CPU than even the 3.
I do recall having to use a fan to keep it(the CPU not the airspy) cool enough.
You can also use the airspy an a generic receiver for VHF and most of UHF. Acars, Weafax, Aircraft voice, GMDSS(Boat ADS-B), and just about anything between about 30Mhz and ADS-B.

Not sure if I mentioned that the airspy is deaf without an amp.
This works really well but so would any decent amp/filter
https://v3.airspy.us/product/upu-fp1090s/


#17

Or the RSP1A with 14 bits, 2 more than the Mini, and includes MW and FM filters as well.

It also includes bias T. The RTL-SDR Blog amp/filter combo is a perfect match for it.

Around the same price too.


#18

Did you noticed any improvement with the 3+, I did not.

Still waiting for the Asus Tinkerboard S to become hardware, it still is vaporware for the most part.


#19

The airspy website mentions that the 3 can get very hot decoding ADS-B.
Bear in mind that some of the settings look like they are for the 3 not the 3+.
https://airspy.com/quickstart/

If the RSP1A will decode ADS-B then give it a try. The extra filters would be nice.


#20

Radarcape vs (DVBT+Pi) = $ vs ¢