ok - but the amp inside the fa dongle. and this where the problem starts - when you want to use a filter in front of lna the filter MUST have very low insertion loss (below -1db) and most filters have muuuch higher insertion loss and/or have much too wide passband and/or too low attenuation ā¦
edit: and even then it sometimes makes sense to place the filter behind lna - see my picture in start-post that shows my standard all-day setup The Final Filter Shootout
@TomMuc - if you donāt have the Ā£Ā£ to spend then homemade is the way to go even if you donāt eventually use it. No loss of Ā£Ā£ but some learning on the way.
Iāll put the jetvision cavity filter on my Xmas list.
@triggers homemade can be great - thatās how jetvision started with their beast, cavity filter etc but i donāt know whether you have to spend so much money for the 3-pole/cavity filter. maybe the generic 10Ā£ china dongle in combination with uputronics saw/lna 40Ā£ could improve your site nearly the same amount. moreover you are from the uk where uputronics also is - anthony is really a very friendly and helpful guy and you would not have to pay the shipping i always have to pay when i order there ā¦
edit: another option if you want to experiment with homemade filters and want to save some money is to just only buy the generic 10Ā£ china dongle and the minicircuits lna for about 3Ā£ or the lna4all for about 16Ā£
I still donāt understand that in RF noisy environment why Uputronics has good performance while ProStick Plus has poor?
Both have:
Same configuration (in from antenna >> lna >> filter >> out to tuner)
Same Filter (TAI SAW 3 dB insertion loss)
a porsche and a vw beetle too have the same configuration - that simple 
But dont use exactly the same components.
SAW is identical. The only possibility is that Uputronics LNA is of porsche quality, while ProStickPlus LNA is of beetle quality.
Nice diy project
this is nearly the same like the uputronics ceramic/lna - just the ceramic filter is 27$
DIY involving soldering of Surface Mounted Components?
My eyes and hands dont cooperate!
Did you try again? Any progress?
donāt know where you have the information from - they look similar - thatās the only thing i can say without information from both manufacturers. and even if they would look identically you never can say they are the same ā¦
Been having āissuesā.
One Pi went intermittent for a day (Pi running, RTL detected, just no received signals). It just came good by itself so I have no idea what the problem was (will be). Tried to follow your instructions, but got an error part way through. SD card then failed to format leaving me with another unknown. Picked up a spare SD card, but got distracted building antennas. New laptop battery arrived today so Iām now back with a PC I can leave running.
Iād like to get the new antenna up on the roof, but weāve been having āa bit of weatherā here, so there will no roof climbing for a a few days
RTL_Power has now been running (successfully) for two hours, so Iāve now got a baseline to reference. At least I would if itāll let me save it. (it didnāt)
May be missing packages rtl-sdr or python-imaging. Give these 4 commands before running scan command. If a package or file is missing, it will be installed/downloaded.
(1) sudo apt-get update
(2) sudo apt-get install rtl-sdr
(3) sudo apt-get install python-imaging
(4) wget https://raw.githubusercontent.com/keenerd/rtl-sdr-misc/master/heatmap/heatmap.py
Is rtl_power running on RPi or on Windows Laptop?
Thanks, Iāll try it on a Pi again later. For now, Iāve moved to win7.
Iāve now got a nights worth of unfiltered noise as a reference and currently recording with the shorted 1/4 Ī» in place.
Now to workout how to post-process the csv.
Iāve installed Python 3, but unsure how to proceed with heatmap.
Initial view suggests mobile phone service on 770, 950 and 1700MHz
already posted for you every single step: The Final Filter Shootout - #89 by TomMuc
edit: and if that still does not work for you - maybe open a new thread āsearch help for plotting frequency scansā - or simply read the tons of already existing threads/posts here in the forum ā¦
Thanks TomMuc, I followed your instructions for the Pi and got an error at ācmake ā¦ā
I abandoned the Pi and (as above) installed a windows version.
I did a quick search on this forum for āheatmap.pyā and only came up with 6 hits - all Pi/linux.
Sorry if this is getting painful, but Iām trying to generate the plots you asked for. If you are loosing interest as fast as I am, Iām happy to cut my losses.
you said you built a homemade filter with great results - thatās why i was asking for some data that shows/proves this. search for ārtl_powerā brings a bunch of results here and in google. to plot already existing csv only the python install is needed. no question this thread is not about how to run python scripts on windows.
I donāt think I said anything of the sort. I made two claims:
1/
2/
I am happy to be challenged on either claim.
