Flamingo AM - Broadcast AM Bandstop Filter (AM Notch Filter) for Software Defined Radio (SDR) Applications

If you need a filter for the AM broadcast band either for SDR purposes or test and measurement purposes… This is a nice inexpensive option.You can do better but you will spend 5 to 10 times as much money to get better performance.This is a nice inexpensive product and a nice package with a common connector style that you can work with.Things you need to know about this unit:The SMA connectors are a little fragile. If you want to install some adapters on them to convert them to type-N or TNC or install a DC block you may need to be careful. I managed to snap one off and have to solder it back on. I successfully repaired my filter with little effort and it swept fine after the fact so no harm done.The performance of my filter was in line with what the manufacture specified according to my VNA. I would like the shelf to be a little sharper, but as I said to get that you have to pay a lot more money.This filter is easily good enough to take harmonic measurements for AM Broadcast if you have a good spectrum analyzer, and it will work well to protect your receiver if that’s what you’re looking for.You should not transmit through this filter, and it does not voltage pass, so you should install a DC block to protect the filter.

And yes, I tried it both directions, it doesn't matter, same result both ways.I bought this because I live fairly close to an AM tower and it has a tendency to overpower everything. I wanted to just filter out the whole AM band to allow me to get into HF/SW and such. This looked to be like the kind of device I needed, but in practice it seemed to do the exact opposite. Not only did it not filter out AM, it seems to make AM less noisy. Broadcasts are even more cleanly defined in sdr programs, it's really got me scratching my head.To be thorough, I ordered the AM filter from rtl-sdr-blog (also available here on Amazon) and that one does exactly what I was expecting. So I guess if I have to choose between the two, I'd go with that one, but knowing my experience seems to be completely anecdotal.I'm going to keep the flamingo in case I ever get into AM stuff, it'll be fun to run some experiments with. At the price point it doesn't break the bank, just disappointed it didn't do what I was led to believe it would.

My SDRplay RSP2PRO was un-usable for NDB beacon search.(209 to 520 KHz) Local AM stations were killing me. My SDRplay can now hear everything my ICOM IC7300 hears. Bought a second filter for my Malahit-DSP SDR radio. The Flamingo filter is in a nice aluminum case. Solid construction and clean design. Insertion loss is about 1 dB above and below the AM band. Great little filter.

This item will not completely eliminate offended Broadcast yay-em QRM from your receiver, however it absolutely attenuates Broadcast yay-em enough to reduce the burden on the receiver's front end and built in filters. I'm using this in conjunction with an 'Uno' and I can now use the RF gain at any level without overloading the front end and I no longer hear/see the nearby biblestation every 20khz, every band. Good bang for the buck and worth the extra couple dollars for the aluminum enclosure over the "bare bones" listing.

This little filter really cleans up the AM broadcast overload when listening below 500 KHz on my Afedri and Airspy SDR's

I am using this AM broadcast band filter with my NoElec upconverter along with a GNURadio synchronous AM shortwave receiver I designed. It removes the AM MW signals which were causing intermod signals in the shortwave bands. A nice nice solid little unit. I highly recommend this product!

Arrived quickly and works well to reduce MW broadcast overload on simple SDRs

The maximum attenuation I measured was 37 dB at 1171 kHz and the minimum attenuation within the stop band was 22 dB at 905 kHz. This is really a 20 dB stop band filter, not quite the 40 dB they claimed. Still works, but not quite the brick wall that was promised. There is 0.37 dB of insertion loss at 3 MHz so the insertion loss isn't bad.

Funciona muy bien, me gustó mucho.Lo recomiendo.

Small, compact unit, easy to set up.I have a very loud local AM station on 610 kHz. Harmonics and intermod up to 5 MHz until I bought this filter. Thumbs up!

The filter is exactly as described and comes in a robust metal case.

HF用コンバーターの前段に使うとSN比に効果があります。

I live beside 4 broadcast towers. I ended up using two of these daisy chained for even better nulls. I think for 99% of people, one of these will be sufficient. It stopped the repeating MW stations into HF.