Built my first antenna and doubled my coverage

[tjowen]

@mattbna

@tjowen

I know you went over the filter before the amp. But to me, why would you want to amplify the signals you’re trying not to see? Wouldn’t it make sense to filter the unwanted signals before amplifying the wanted?

In the big scheme of things, that really doesn’t matter all that much as the SDR dongle should only be concerned with the frequency you (well, Dump1090 anyway) have it tuned to anyway (with a little bit of bleed-over on either side).

Allowing whatever the antenna is able to pull in to hit the amplifier input with no added signal loss (insertion loss from a filter) is a better idea than immediately dropping the signal level of everything the antenna receives at 1090MHz (in our situation) and then amplifying the now lower input signal to the amp. This is the same reason why we like to have the amp as close as possible to the antenna - to provide a strong input to the amp and not lose too much in a long run of cable between the antenna and the amp.

As a completely hypothetical (and simple) example, let’s assume that an aircraft that is 150+ miles away is only hitting us with -10dB in the first place. I would much rather add 25dB to that and then take away 1.5dB at the filter than immediately take that 1.5dB away straight off the antenna and be left with an even lower input level (now -11.5dB) to amplify. Amplifiers work better when they’re not trying to scrape the bottom of the barrel, which generally gives you ‘quiet garbage in, loud garbage out’ to work with.

The VBFZ-1065-S+ filter does an excellent job of attenuating anything outside the 980-1150MHz range, which removes a large portion of the junk right before our nice amplified signal hits our SDR dongle.

@tjowen

If the filter ends up dropping the overall signal too much than maybe two amps will be required. One before and one after the amp.

There could be situations where that may make sense, but there would need to be much longer lengths of coax involved than the setup we’ve recently seen pics of. He doesn’t appear to have more than 5ft of coax involved as a whole - which means that two amplifiers would be, among other things, massive overkill at his SDR dongle. It would be ideal to never need more than one amplifier as they also have some insertion loss and noise that they’re going to add to the equation. While the insertion loss can be somewhat managed, you can’t help but amplify with the second amp whatever noise the first amp has added to the mix.

With regard to amplifiers, I’m going to write up a forum post sometime soon about the three amplifiers that I’ve recently tested for a few weeks each. I originally started out with an Electroline EDA 2200 CATV amp (5-1000MHz w/ 2dB noise figure and 11dB of gain) simply because I still had a few new ones in a box from my cable tech days. I then switched to the PerfectVision PVLA-30 satellite amplifier (950-2150MHz with 6dB noise figure and 30dB of gain), which a lot of folks around here swear by. For $14 - why not?

I quickly learned that it was not as impressive as I had hoped it would be and am inclined to blame it’s insertion loss and noise issues for the shorter range that it was providing for me. The Electroline amps are very well built, aren’t cheap, and have some of the lowest noise of any amp used in the CATV industry. The PerfectVision amps are small and powerful…but what should I really expect from an amp that you can find at K-Mart for under $20 (and is built for pennies in China, I’m quite sure)? Needless to say, it didn’t surprise me that an amp that claims 3x the output power of the Electroline was ultimately performing worse than what it replaced.

I’m now using a Mini-Circuits ZRL-2400LN+ low-noise amplifier (found a killer deal on four of them brand new on eBay), which is about as good of an amp as I’ll ever get for this little ADS-B hobby. These little gems are tuned for 1000-2400mHZ with a 1.2dB noise figure and around 28-31dB of gain. After running one of them for a little over a week, I quickly decided that the PerfectVision amp will make a nice target at 100-yards the next time I’m on the rifle range.

In order to keep the new amp out of the attic and in the air conditioning for the summer (stupid hot in Nashville this time of year), I extended the RG6/U feed line from the roof-mounted antenna by another 15ft or so and moved the amp down to a shelf in the laundry room. Even with the added length to the feed line between the antenna and the amp, this thing makes the PerfectVision amp look like…well…the $14 eBay amp that it is. My daily position counts are now around 20k-25k higher and aircraft count is up by 500-600 per day - with the longer feed line and the new amp being the only things I’ve changed. Works for me.–

Thank you for the very detailed reply Matt to my simplistic approach. I look forward to your amplifier write up.
…Tom

[mattbna]

@moone

Anyone want to buy an filter? No Guarantees!!

Simply removed the filter, put it back to the configuration prior to the filter, the 8080 was showing 4 planes in the area. Unplugged the Pi so that it would reboot and there were a lot more planes all of a sudden. Like 15 planes…

There is something else going on here that we haven’t figured out as of yet. The chances of the filter alone causing this issue are very slim. I’ve installed quite a few of the exact same filter and have never seen issues like this. At the same time, I refuse (as a former Comcast data/fiber field tech for around a decade) to be in the same room with twist-on coax end fittings. It’s instinct for any cable tech that’s worth anything to automatically change out every twist-on fitting we see with quality snap-and-seal fittings whenever required. If gold store-bought splitters and twist-on coax fittings didn’t exist, the cable companies wouldn’t need nearly as many techs as they currently employ. Those items are the ultimate source of all sorts of problems at literally hundreds of thousands of service calls every year.

I do understand that this is a hobby and certainly wouldn’t expect you to go out and buy a cable stripping tool, expensive fittings, and a fitting compression tool just to slap a FlighAware feeder setup together on your roof.

That said, I’m curious to know how you went about stripping the coax prior to installing those lovely twist-on fittings, and how much (or how little) of the copper center-conductor you left sticking out beyond the end of the fittings? Just because you’re using twist-on fittings, that doesn’t necessarily mean that they can’t work just fine for this project (if they’re installed correctly).

Unless you somehow got a screwy filter (not likely), something has to be physically wrong somewhere in your setup for the filter install to kill your numbers to the degree that it did. I’m going to guess that the problem is somewhere within the adapters you used when inserting the filter between the power inserter and the SDR dongle (red circles). I’m curious to know if you’d be willing to unscrew the short coax jumper you had running between the power inserter and the filter and provide us with some clear photos looking down in to the coax fittings on each end of that little cable (green arrow)? Small imperfections with adapters, fittings, etc. can lead to big problems when dealing with frequencies in the 1GHz range, which may very well be what we’re dealing with here.

https://dl.dropboxusercontent.com/u/8750282/LiveATC/filter_setup1.jpg

As for as your setup on the roof, your antenna location is fine and there is no reason to worry about moving it away from the dish. Your spider is higher than the dish and the metal from the dish isn’t going to block any aircraft signals that low to the ground anyway.

With your current setup and plenty of open sky, you could get away with adding a longer piece of coax to the end of the antenna and moving the amp, Pi, etc. inside without noticing much of a difference in aircraft count. I know you said that it’s not going to rain for a while, but if it should so much a sprinkle once with all of that stuff out there, it will all be ruined.

Also, getting the Pi and dongle (in particular) inside will at least somewhat help to shield the dongle from the insane amount of RF that it is absorbing by being out in the open on your roof.

---

As a side note, ‘rebooting’ your Pi by simply unplugging it is really not a good idea and will, after enough of those, almost certainly lead to corrupt data on your SD card (which means you’ll get to start all over again). In testing, I’ve seen as few as 4-5 power-loss reboots destroy the OS install on a MicroSD card.

To properly shutdown a Pi, you need to first log-in to it and issue the proper shutdown / halt command - but we’ll get to that later.

In the case of modifying your RF chain, there is no need to reboot the Pi as it has no idea what you’re doing out there anyway. Once you’ve made whatever changes you’re making, it’ll start receiving the better (or worse) data from aircraft and take care of things on it’s own.

Based on the numbers you’re already putting up on your stats page and your rather prime location near the Bay Area, there is no reason why you couldn’t be putting up much higher numbers with some setup tweaking. You’re already doing better than most folks that are much closer to SFO/OAK/SJO, and with some help from the good people in these forums, I’m sure we can get you running even better.

Matt

–

[tjowen]

@mattbna

@tjowen

I know you went over the filter before the amp. But to me, why would you want to amplify the signals you’re trying not to see? Wouldn’t it make sense to filter the unwanted signals before amplifying the wanted?

In the big scheme of things, that really doesn’t matter all that much as the SDR dongle should only be concerned with the frequency you (well, Dump1090 anyway) have it tuned to anyway (with a little bit of bleed-over on either side).

Allowing whatever the antenna is able to pull in to hit the amplifier input with no added signal loss (insertion loss from a filter) is a better idea than immediately dropping the signal level of everything the antenna receives at 1090MHz (in our situation) and then amplifying the now lower input signal to the amp. This is the same reason why we like to have the amp as close as possible to the antenna - to provide a strong input to the amp and not lose too much in a long run of cable between the antenna and the amp.

As a completely hypothetical (and simple) example, let’s assume that an aircraft that is 150+ miles away is only hitting us with -10dB in the first place. I would much rather add 25dB to that and then take away 1.5dB at the filter than immediately take that 1.5dB away straight off the antenna and be left with an even lower input level (now -11.5dB) to amplify. Amplifiers work better when they’re not trying to scrape the bottom of the barrel, which generally gives you ‘quiet garbage in, loud garbage out’ to work with.

The VBFZ-1065-S+ filter does an excellent job of attenuating anything outside the 980-1150MHz range, which removes a large portion of the junk right before our nice amplified signal hits our SDR dongle.

@tjowen

If the filter ends up dropping the overall signal too much than maybe two amps will be required. One before and one after the amp.

There could be situations where that may make sense, but there would need to be much longer lengths of coax involved than the setup we’ve recently seen pics of. He doesn’t appear to have more than 5ft of coax involved as a whole - which means that two amplifiers would be, among other things, massive overkill at his SDR dongle. It would be ideal to never need more than one amplifier as they also have some insertion loss and noise that they’re going to add to the equation. While the insertion loss can be somewhat managed, you can’t help but amplify with the second amp whatever noise the first amp has added to the mix.

With regard to amplifiers, I’m going to write up a forum post sometime soon about the three amplifiers that I’ve recently tested for a few weeks each. I originally started out with an Electroline EDA 2200 CATV amp (5-1000MHz w/ 2dB noise figure and 11dB of gain) simply because I still had a few new ones in a box from my cable tech days. I then switched to the PerfectVision PVLA-30 satellite amplifier (950-2150MHz with 6dB noise figure and 30dB of gain), which a lot of folks around here swear by. For $14 - why not?

I quickly learned that it was not as impressive as I had hoped it would be and am inclined to blame it’s insertion loss and noise issues for the shorter range that it was providing for me. The Electroline amps are very well built, aren’t cheap, and have some of the lowest noise of any amp used in the CATV industry. The PerfectVision amps are small and powerful…but what should I really expect from an amp that you can find at K-Mart for under $20 (and is built for pennies in China, I’m quite sure)? Needless to say, it didn’t surprise me that an amp that claims 3x the output power of the Electroline was ultimately performing worse than what it replaced.

I’m now using a Mini-Circuits ZRL-2400LN+ low-noise amplifier (found a killer deal on four of them brand new on eBay), which is about as good of an amp as I’ll ever get for this little ADS-B hobby. These little gems are tuned for 1000-2400mHZ with a 1.2dB noise figure and around 28-31dB of gain. After running one of them for a little over a week, I quickly decided that the PerfectVision amp will make a nice target at 100-yards the next time I’m on the rifle range.

In order to keep the new amp out of the attic and in the air conditioning for the summer (stupid hot in Nashville this time of year), I extended the RG6/U feed line from the roof-mounted antenna by another 15ft or so and moved the amp down to a shelf in the laundry room. Even with the added length to the feed line between the antenna and the amp, this thing makes the PerfectVision amp look like…well…the $14 eBay amp that it is. My daily position counts are now around 20k-25k higher and aircraft count is up by 500-600 per day - with the longer feed line and the new amp being the only things I’ve changed. Works for me.

Matt,
My experience with the Perfect Vision amp has been the complete opposite to yours and I am wondering why. What did we do differently to have such opposing views?

If you look at my stats page you’ll find two feeding sites, 6458 & 8130. And here is their configuration, at present.

site 6458, CoCo antenna—5m RG6—Nevis LNA/filter—Dongle—RPi2
site 8130, Spider—5m RG6—Perfect Vision Amp—Power/Inserter—Splitter—Dongle—BPi

The two sites report almost the same stats, except the spider’s RF reports slightly less due to being mounted 1.5m lower. And I can swap the RF chains from box-to-box and the same pattern follows within the stats.

The biggest light-bulb moment for me with the Perfect Vision amp was when I was playing with the splitter. The splitter has 3db insertion loss, so I figured that I would see a reduction in range and/or aircraft spotted, but the opposite was the case. So, the only thing I can figure is that perhaps the PV amp was over-driving the dongle and the added splitter loss helped the dongle in AGC mode to handle the signal better.

To eliminate other factors that the splitter might be causing, I plan on trying a simple 3db pad to see the effect.
…Tom

[moone]

@mattbna

@moone

Anyone want to buy an filter? No Guarantees!!

Simply removed the filter, put it back to the configuration prior to the filter, the 8080 was showing 4 planes in the area. Unplugged the Pi so that it would reboot and there were a lot more planes all of a sudden. Like 15 planes…

There is something else going on here that we haven’t figured out as of yet. The chances of the filter alone causing this issue are very slim. I’ve installed quite a few of the exact same filter and have never seen issues like this. At the same time, I refuse (as a former Comcast data/fiber field tech for around a decade) to be in the same room with twist-on coax end fittings. It’s instinct for any cable tech that’s worth anything to automatically change out every twist-on fitting we see with quality snap-and-seal fittings whenever required. If gold store-bought splitters and twist-on coax fittings didn’t exist, the cable companies wouldn’t need nearly as many techs as they currently employ. Those items are the ultimate source of all sorts of problems at literally hundreds of thousands of service calls every year.

I do understand that this is a hobby and certainly wouldn’t expect you to go out and buy a cable stripping tool, expensive fittings, and a fitting compression tool just to slap a FlighAware feeder setup together on your roof.

That said, I’m curious to know how you went about stripping the coax prior to installing those lovely twist-on fittings, and how much (or how little) of the copper center-conductor you left sticking out beyond the end of the fittings? Just because you’re using twist-on fittings, that doesn’t necessarily mean that they can’t work just fine for this project (if they’re installed correctly).

Unless you somehow got a screwy filter (not likely), something has to be physically wrong somewhere in your setup for the filter install to kill your numbers to the degree that it did. I’m going to guess that the problem is somewhere within the adapters you used when inserting the filter between the power inserter and the SDR dongle (red circles). I’m curious to know if you’d be willing to unscrew the short coax jumper you had running between the power inserter and the filter and provide us with some clear photos looking down in to the coax fittings on each end of that little cable (green arrow)? Small imperfections with adapters, fittings, etc. can lead to big problems when dealing with frequencies in the 1GHz range, which may very well be what we’re dealing with here.

https://dl.dropboxusercontent.com/u/8750282/LiveATC/filter_setup1.jpg

As for as your setup on the roof, your antenna location is fine and there is no reason to worry about moving it away from the dish. Your spider is higher than the dish and the metal from the dish isn’t going to block any aircraft signals that low to the ground anyway.

With your current setup and plenty of open sky, you could get away with adding a longer piece of coax to the end of the antenna and moving the amp, Pi, etc. inside without noticing much of a difference in aircraft count. I know you said that it’s not going to rain for a while, but if it should so much a sprinkle once with all of that stuff out there, it will all be ruined.

Also, getting the Pi and dongle (in particular) inside will at least somewhat help to shield the dongle from the insane amount of RF that it is absorbing by being out in the open on your roof.

---

As a side note, ‘rebooting’ your Pi by simply unplugging it is really not a good idea and will, after enough of those, almost certainly lead to corrupt data on your SD card (which means you’ll get to start all over again). In testing, I’ve seen as few as 4-5 power-loss reboots destroy the OS install on a MicroSD card.

To properly shutdown a Pi, you need to first log-in to it and issue the proper shutdown / halt command - but we’ll get to that later.

In the case of modifying your RF chain, there is no need to reboot the Pi as it has no idea what you’re doing out there anyway. Once you’ve made whatever changes you’re making, it’ll start receiving the better (or worse) data from aircraft and take care of things on it’s own.

Based on the numbers you’re already putting up on your stats page and your rather prime location near the Bay Area, there is no reason why you couldn’t be putting up much higher numbers with some setup tweaking. You’re already doing better than most folks that are much closer to SFO/OAK/SJO, and with some help from the good people in these forums, I’m sure we can get you running even better.

Matt

–

THANKS to all.

After I get back to work today I am going to check the continuity of the filter with the connectors and see if that is the problem.

Every time I change the antenna, coke can to spider or unhook the cables to install the amp it can take several hours for the system to start reading?? Kinda impossible to go in and hook it to a monitor and issue the command to reboot. Can this be done on the stats page?

I am certainly interested in learning how to get the most of this system so any and all advice is valuable.

Will post the continuity of the filter arrangement after I get back from flying this morning. By the way, I had removed that short piece of coaxial cable originally and it still did not report anything so I put it back in as an attempt to get the system to read again. I have it installed right not so I have to feel it works. Why screw on ends… Simple, easy, cheap and I had never put an end on a coaxial cable before so I had to try something to start with and them improve from there.

[moone]

Well, I have found the problem. Why I don’t currently know and how to remedy might be simple but here’s the problem.

dropbox.com/s/ysh2f7jf1h435 … 3.jpg?dl=0

dropbox.com/s/u9qm3oqze4toi … 9.jpg?dl=0

dropbox.com/s/xewvfi0qqxm55 … 2.jpg?dl=0

Didn’t even get to work and I saw that there’s no wire inside the adapters to make the connection between the SMA to the F type adapter on one end… So essentially there was no antenna feed going into the Dongle.

Wonder if I can just pull one of these wires out of another connector and insert into this one… hmmmm??

Also wonder which is wrong, the filter or the adapter, common sense says the adapter…

[abcd567]

@moone

THANKS to all.
…snip…
Every time I change the antenna, coke can to spider or unhook the cables to install the amp it can take several hours for the system to start reading?? Kinda impossible to go in and hook it to a monitor and issue the command to reboot. Can this be done on the stats page?
…snip…

Yes, you can give commands to your RPi from Flightaware stats page, if you are logged in to the webpage.

Step 1: on your stats page, go to the last line in control panel titled “send command to device”

https://farm1.staticflickr.com/259/19129568436_8d3e252bd5_o.png

Step 2: click text entry to open a dropdown menue and select “Reboot device”

https://farm1.staticflickr.com/343/18533278574_28f7be61c3_o.png

Step 3: After “Reboot device” displays in text box, click “send command” button

https://farm1.staticflickr.com/302/18968269678_2078dd7c03_o.png

[moone]

Thanks!

[eaglemark]

@moone

Well, I have found the problem. Why I don’t currently know and how to remedy might be simple but here’s the problem.

dropbox.com/s/ysh2f7jf1h435 … 3.jpg?dl=0

dropbox.com/s/u9qm3oqze4toi … 9.jpg?dl=0

dropbox.com/s/xewvfi0qqxm55 … 2.jpg?dl=0

Didn’t even get to work and I saw that there’s no wire inside the adapters to make the connection between the SMA to the F type adapter on one end… So essentially there was no antenna feed going into the Dongle.

Wonder if I can just pull one of these wires out of another connector and insert into this one… hmmmm??

Also wonder which is wrong, the filter or the adapter, common sense says the adapter…

Looks like your adapter is reverse sex. For a quick test you may be able to put some wire in to allow
it to make connection. But for a solid fix I would get the right adapter and move it out of the weather.

[LCOVA76]

Looks like youre adaptors are RP-SMA… and the filter is SMA…

Here are the differences.

@moone

Well, I have found the problem. Why I don’t currently know and how to remedy might be simple but here’s the problem.

dropbox.com/s/ysh2f7jf1h435 … 3.jpg?dl=0

dropbox.com/s/u9qm3oqze4toi … 9.jpg?dl=0

dropbox.com/s/xewvfi0qqxm55 … 2.jpg?dl=0

Didn’t even get to work and I saw that there’s no wire inside the adapters to make the connection between the SMA to the F type adapter on one end… So essentially there was no antenna feed going into the Dongle.

Wonder if I can just pull one of these wires out of another connector and insert into this one… hmmmm??

Also wonder which is wrong, the filter or the adapter, common sense says the adapter…

[tjowen]

@moone

Well, I have found the problem. Why I don’t currently know and how to remedy might be simple but here’s the problem.

dropbox.com/s/ysh2f7jf1h435 … 3.jpg?dl=0

dropbox.com/s/u9qm3oqze4toi … 9.jpg?dl=0

dropbox.com/s/xewvfi0qqxm55 … 2.jpg?dl=0

Didn’t even get to work and I saw that there’s no wire inside the adapters to make the connection between the SMA to the F type adapter on one end… So essentially there was no antenna feed going into the Dongle.

Wonder if I can just pull one of these wires out of another connector and insert into this one… hmmmm??

Also wonder which is wrong, the filter or the adapter, common sense says the adapter…

There is two types of SMA connectors, SMA & RP-SMA. You may have purchased or were shipped the wrong type.
…Tom

[moone]

Thanks, finding this adapter is not that easy. Got one, make that two on ebay a few minutes ago from good old CHINA.

Have to wait a week but have to wait a week for domestic shipping as well so that’s a wash.

It’s been less than 24 hrs since I removed the filter and I have already seen 1,070 planes so the system is working well and now that I have found the problem with the filter setup I have hope again for more.

[tjowen]

@moone

Thanks, finding this adapter is not that easy. Got one, make that two on ebay a few minutes ago from good old CHINA.

Have to wait a week but have to wait a week for domestic shipping as well so that’s a wash.

It’s been less than 24 hrs since I removed the filter and I have already seen 1,070 planes so the system is working well and now that I have found the problem with the filter setup I have hope again for more.

While you wait, cut a couple short pieces of coax centre conductor and try and make the adapters work. I wouldn’t be able to wait for the new adapters to arrive, but that’s just me…
…Tom

[moone]

@tjowen

@moone

Thanks, finding this adapter is not that easy. Got one, make that two on ebay a few minutes ago from good old CHINA.

Have to wait a week but have to wait a week for domestic shipping as well so that’s a wash.

It’s been less than 24 hrs since I removed the filter and I have already seen 1,070 planes so the system is working well and now that I have found the problem with the filter setup I have hope again for more.

While you wait, cut a couple short pieces of coax centre conductor and try and make the adapters work. I wouldn’t be able to wait for the new adapters to arrive, but that’s just me…
…Tom

Funny you said that… I immediately went and cut a 2" piece off the coaxial bundle… Stripped it and though this is going to be easy… To large of a diameter!!! Will not fit in either end… Then I ordered a new end.

Measured the coaxial rod at 0.04" or 1mm and the SMA is 0.036" so I might take a razor blade and scrap the wire down a bit and try it.

[tjowen]

@moone

@tjowen

@moone

Thanks, finding this adapter is not that easy. Got one, make that two on ebay a few minutes ago from good old CHINA.

Have to wait a week but have to wait a week for domestic shipping as well so that’s a wash.

It’s been less than 24 hrs since I removed the filter and I have already seen 1,070 planes so the system is working well and now that I have found the problem with the filter setup I have hope again for more.

While you wait, cut a couple short pieces of coax centre conductor and try and make the adapters work. I wouldn’t be able to wait for the new adapters to arrive, but that’s just me…
…Tom

Funny you said that… I immediately went and cut a 2" piece off the coaxial bundle… Stripped it and though this is going to be easy… To large of a diameter!!! Will not fit in either end… Then I ordered a new end.

Measured the coaxial rod at 0.04" or 1mm and the SMA is 0.036" so I might take a razor blade and scrap the wire down a bit and try it.

1 mm dia is 18 awg. If you have any single components like resistors, capacitors or diodes you may find one or more with the right gauge wire leads attached.

P.S. do you have a pneumatic brad nailer? Some use 18 gauge brad nails.
…Tom

[mattbna]

@moone

Wonder if I can just pull one of these wires out of another connector and insert into this one… hmmmm??

I really wouldn’t recommend that as it’s not worth taking a chance at damaging the pins inside that $40 filter - and you likely don’t have any wire that is as thin as what would be sticking out of a male SMA plug. The filter is just an added bonus for your setup, which is already working well without it. Just wait for your adapter to arrive.

@moone

Also wonder which is wrong, the filter or the adapter, common sense says the adapter…

The filters only come one way, and actually needing an RP-SMA adapter for something is pretty rare.

Guessing you just hooked the filter and the adapter together and didn’t look to make sure they would actually mate together correctly?

@moone

Thanks, finding this adapter is not that easy. Got one, make that two on ebay a few minutes ago from good old CHINA.

Actually, they stock them in just about every Amazon distribution center in the country and you can get one within 2-3 days (4-5 days with free shipping). I just ordered a few more F-Female to SMA-Male adapters on Monday night and they arrived today.

You have two realistic options that are actually stocked and shipped by Amazon, which means they’ll arrive quickly:

http://amzn.com/B00BIMTGXQ

http://amzn.com/B00CQ35NOW

This is the adapter you’d need to go directly from the output of the filter to the MCX input on your USB dongle, which would eliminate chaining multiple adapters together (which it appears you were doing in your original photos):

http://amzn.com/B00CP17WMG

You can see one of each of the adapters I’ve linked to above in-use in the photo I posted in this thread a few days ago:

https://www.dropbox.com/s/t0uzsobounal7w1/0426150220-2.png

Matt

–

[abcd567]

I have never used PerfectVision or MiniCircuit’s Amplifier. The only amplifier I have used is RCA D903, which I purchased from a local Hobby & Eectronics Store for $4.

I am using it since 2 years, and am very satisfied with it.

Here is the picture of my first setup which I made 2 years ago:
A halfwave dipole → Amplifier-> 50 ft/15m RG6 coax->DVB-T dongle->Desktop (Windows).

[PeterHR]

I suspect that all these amplifiers are pretty similar - the main difference is what’s printed on the casing.

What ha made most difference on my Pi B was doing sudo raspi-config and overclocking it to ‘medium’ - it’s lifted my message count on dump1090 by almost 20%.

[mattbna]

@PeterHR

I suspect that all these amplifiers are pretty similar - the main difference is what’s printed on the casing.

With regard to the in-line satellite amps that can be purchased in retail stores for anywhere from $4 to $20 - I completely agree.

Matt

–

[moone]

Well curiosity got the best of me and I took the coaxial core and put it in a lathe and took two files and spun the wire between them until I had the diameter down to 0/035" and then the wire fit!!!

Cut the wire at a good length and put the filter and adapter arrangement back together.

Went and installed the filter back in the system and it appears to be working now.

Before Filter: dropbox.com/s/82ezfc3x4tueo … 4.jpg?dl=0

Filter install: dropbox.com/s/a3k0493jbykwk … 1.jpg?dl=0

After install: dropbox.com/s/e6228jvnswbsy … 3.jpg?dl=0

Not a lot of difference. Note: I used the command line to reboot the Pi as I didn’t want to wait hours for the filter installation to take place. Up and running in a matter of 10 minutes from start to finish.

[moone]

@PeterHR

I suspect that all these amplifiers are pretty similar - the main difference is what’s printed on the casing.

What ha made most difference on my Pi B was doing sudo raspi-config and overclocking it to ‘medium’ - it’s lifted my message count on dump1090 by almost 20%.

Ok. Please tell me more… How does this voodoo magic work?