Extending my setup with a filter and/or amplifier


#1

Hi there!

My setup is running fine so far and i’m tracking a lot of planes.
But i’m thinking of extending the setup with the flightaware band pass filter and i have the following questions:

  • i am using a 8 legged spider antenna connected to a 5m 75ohm cable. Where should i place the filter? right after the antenna or before the pigtail to tge usb dongle?

  • i’m fine with the 5m cable and i will not need more than that, is it useful to have an amplifier in my setup? if so, where should i place it? at the antenna side of the cable before or after the filter or at the end going to the receiver and also there before or after the filter?

  • since my electro/engineer knowledge is limited i also want to ask if in case an amplifier is useful which amplifier you can recommend (which specs should it have)?

Thanks in advance :slight_smile:


#2
  • i am using a 8 legged spider antenna connected to a 5m 75ohm cable. Where should i place the filter? right after the antenna or before the pigtail to tge usb dongle?

You will not see a difference. Either way is identical performance. I suggest placing it where it is easier to connect and safe from weather. This is usually near the dongle.

  • i’m fine with the 5m cable and i will not need more than that, is it useful to have an amplifier in my setup? if so, where should i place it? at the antenna side of the cable before or after the filter or at the end going to the receiver and also there before or after the filter?

Can you wait a week? There might be something new that will solve your exact problem.

  • since my electro/engineer knowledge is limited i also want to ask if in case an amplifier is useful which amplifier you can recommend (which specs should it have)?

Definitely wait a week :slight_smile:


#3

You tease, you… :stuck_out_tongue:


#4

[quote=“david.baker”]-

Can you wait a week? There might be something new that will solve your exact problem.

Definitely wait a week :slight_smile:
[/quote]

Interesting and intriguing. :astonished:
When its ready, Will this item be available in Europe David ?

I take it we have to pay for it if we want one :laughing:

Best Regards,
Mike


#5

Okay, so i guess i will come back in a week and ask again :smiley:

I also hope that this thing will be available in europe :slight_smile:


#6

How about a free gift for feeders, as a reverse birthday present for FA’s 11th Birthday :laughing:


#7

I sure hope it’s a weatherproof inline LNA with n connectors and an integrated dc block that fits nicely on the bottom of the FA antenna, and a matching SMA power injector for the inside.

I cant be the only user who would love this :smiley: crossing my fingers


#8

Racing stripes don’t hurt none either. :mrgreen:


#9

yes racing stripes, tinted windows, and neon undercarriage lighting as well will assuredly help the antenna go faster. oh and a nitrous oxide boost to improve SNR would be delightful :laughing:


#10

Balloon mount for greater range??? :wink:

Cheers!
LitterBug


#11

.
May be something like this inside a weather proof case.

LNA, 35 dB, 40 Mhz to 2.5 Ghz


#12

Getting some great results from a special order version of the HABAmp Amplifier and Saw Filter combined.
Company owner Anthony Stirk made this one for me with alternative supply voltage on the bias tee as my PSU is 12vdc.
This custom one is fitted with regulator that is good for anything from 5-26 volts up the coaxial.
This one has been hand soldered by him as it was a one off.
The regular model is soldered by robot at a plant right here in the UK.
This unit is a fair old weight for its size.
Great build quality for the price. Very Impressed.

Im currently testing it on my pi b+ experimental station with indoor spider running adsb-receiver project, please take a look (link to site below).

http://mersey-radar.no-ip.org

Im feeding the HABAmp with 5 vdc at the mini usb socket at present from an ipad charger, very convienient.

Setting the gain on the dongle requires some considerable experimenting with values so there have been a few restarts of d1090 during testing.
I have tried values between 20 and max, seems best at around 30-32 if my graph reading is right :unamused:

I will definitely be using this on my main station very soon…a trip to the attic me thinks :smiley:

This would be a great station addition for those like me that use commercial sat/tv power supply units.

Only available as special order at the moment via email enquiry to Anthony at Uputronics/Nevis.

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


#13

Have you put that one in service yet? I have the 15dB one from the same vendor. Powered from the RPi GPIO header just fine. Curious how the 35dB one performs.


#14

No, not yet, not even purchased it yet.
The photo is from Planefinder member Richard Lee’s post, who has used it for his antenna testing rig.
Please see his these two posts:

Click Here - Richard Lee’s Post #40

Click Here - Richard Lee’s Post #41

.


#15

Yesterday I added 3ft to the mast my antenna was on and was kind of dismayed, as stats generally went down.

Today I removed the 30db LNA and connected the 25ft feedline directly to the dongle (through FA bandpass, mind you) and set dongle gain to max.

Stats went way way up. 1000+msg/sec, 160 aircraft tracked.

Perhaps amplifiers should be a last resort after all.


#16

This is where having the graphs from collectd really help. You can see if you are getting overloaded with noise. Amps can end up amplifying more noise than signal.

You could probably get get more airfcraft with the amp but you need to work out the best gain setting on the dongle. Amps are best used at the antenna feed point to compensate for the line loss.

I am glad to see the 1000msg/sec works. I get 500-600 but my antenna is inside. When I move it outside, above the local house rooflines, I expect to get higher. At the moment I am terrain or house blocked from seeing ac coming into JFK, only 15NM away. Sometimes I can see ac on the ground at lga and ewr, but the conditions have to be right. I should be able to see all class A airspace in NJ and Long Island when I am done.


#17

@JonHanford
@jonhawkes2030

**Both of my antennas are indoor, and length of RG6 coax is 12ft/4m. I don’t use any amplifier or filter. **

Messages/sec heavily depends on air traffic flow around antenna location, not only on system (antenna, coax, amplifier, settings etc). I get 400-500 messages/sec during high traffic hours.

The maximum range is an important parameter for system performance. Cantenna give 240 nautical miles (275 miles) and Coco gives 235 nautical miles (265 miles). The average of Coco looks higher than that of Cantenna, but this is due to fact that Coco graph has not yet completed 24 hrs and has not passed through dip during the period between 1am in night and 4 am early morning.

RPi Model 2 with Cantenna

RPi B+ with 8 element diy Coco + impedance matching components

.


#18

You’re probably right. Upon hooking up the removed amp to a computer running SDR# - as it happens it’s not amplifying anything at all. Actually it’s just functioning as a -10db attenuator at this point. :unamused:

It definitely was working at one point, but . Might have fried it with reverse polarity for a second or maybe it just went DOA after a bit.

I guess I’ll wait for FA’s surprise next week before ordering a new one. I’d love to have one at the antenna, but it would have to be N connectors and it would have to be weatherproof. I don’t see any point going N-F then F-N to get an off the shelf satamp up there, I feel like the Impedance change and adapter losses would outweigh any signal gain.


#19

I have used a satellite amplifier (RCA D903) for two years without any problem. It helped increase the performance tremendously. At that time I did not have RPi, and DVB-T dongle was plugged into my Windows Desktop which was located at about 50 ft / 15 m from the large glass window which was the antenna location, the best-signal location in my apartment.

Initially I used the antenna with 50 ft RG6 coax without an amplifier, and my range was < 50 kms :cry: .
Next I tried a TV antenna drop amplifier ($18), it made some improvement.
Next I ordered satellite amplifier from eBay, and it acted as an attenuator rather than an amplifier. It was defective.
Finally I found a satellite amplifier (RCA D903) from an electronics & hobby shop in our area for $4 :smiley: and it proved excellent :smiley: .

I used the RCA D903 satellite amplifier for almost 2 years.
I purchased one more and added it to my system, thinking 2 amplifiers will be better than 1 amplifier.
Later when I found that it did not give any further improvement, I removed it.

About an year ago I purchased 2 RPi, placed these below the antennas with coax length only 12 ft / 4 m , and hooked to router by 30 ft / 10 m network cable. With this setup, I am NOT using any amplifier.

Below are 3 photos of my 2013 set up


#20

[quote=“david.baker”]-

Can you wait a week? There might be something new that will solve your exact problem.

Definitely wait a week :slight_smile:
[/quote]

@david.baker
Any further news on this new product in the pipeline from FA ?
Available worldwide ?
Im sure that im not the only one waiting :wink: