Amazon attenuators, any good? - Page 1
Forum section: electronics / testgear

author: W4PJB
author_rank: Regular Contributor
timestamp: January 12, 2024, 04:31:11 pm
content: Has anyone tested any of the inexpensive attenuators from Amazon, or have experience how they would compare to a much more expensive units from companies like Pasternack or MiniCircuits?Here is an example:https://www.amazon.com/BECEN-Male-Female-Connector-Attenuator/dp/B07DXPT3FT/ref=sr_1_8?crid=SM5W8UHDV7B3&keywords=30%2Bdb%2Battenuator%2Bn%2Bconnector&qid=1705076905&sprefix=30%2Bdb%2Battenuator%2Bn%2Bconnector%2Caps%2C92&sr=8-8&th=1Thanks!

author: fourfathom
author_rank: Super Contributor
timestamp: January 12, 2024, 05:12:30 pm
content: I've purchased a few attenuators from Amazon / BECEN. They are usually OK, with decent performance up to 1GHz (at least the smaller-attenuation 10W SMA connector ones I've got) Sorry, I don't have any test data handy. But one 100W "50dB" N-connector one I got from BCEN actually just has about 40dB attenuation. It was reasonably flat over my frequency range of interest, and it managed to handle the 50W or so I ran through it. I put a "40dB" label on it and still use it.These attenuators are commonly available from aliexpress.com, and they all look the same -- I don't know who actually makes them, or where "BECEN" gets theirs. QA rejects, perhaps?So if you are able to test the attenuator before using it, it's probably worth a shot. If you want something with better-guaranteed precision Amazon/BECEN is probably not your best source.And watch out for power ratings on Chinese attenuators and dummy loads. I can buy the exact SMA dummy load, sold as "1W" and "2W" devices. They get pretty hot at 1W.

author: Bud
author_rank: Super Contributor
timestamp: January 12, 2024, 06:18:13 pm
content: For casual use or for Ham radio you can use those, they likely have a vanila axial resistor inside. For use with expensive test and measurement equipment and for measurements i would get one from Minicircuits. The Chinese ones may ruin your equipment connectors because of poor mechanical tolerances. That is beside poor attenuation accuracy, frequency range and return loss.

author: DaJMasta
author_rank: Super Contributor
timestamp: January 12, 2024, 11:11:08 pm
content: For not so much more, you can get used or NOS name brand attenuators on ebay or similar - while they will probably work at least to some degree and that may be enough, as others have said, the real deal as a surplus part will likely be a lot more reliable and better manufactured provided the connectors are in good shape.

author: David Hess
author_rank: Super Contributor
timestamp: January 12, 2024, 11:12:38 pm
content: Quote from: fourfathom on January 12, 2024, 05:12:30 pmI usually consider single stages of attenuation above 20dB to be questionable anyway.

author: DaneLaw
author_rank: Frequent Contributor
timestamp: January 13, 2024, 07:08:26 pm
content: Got two attenuators from "Becen" though with SMA-connectors, and they seem solid - as far as I can tell (with the price in mind).One 5W -40Db that is rated for 3 or 4GHz weight around 45.5g and another 5W but way smaller, also -40db and rated for 13GHz.I don't have linearity to 13Ghz to check it, but with TinySA Ultra 30Mhz test-signal they both at least seem db accurate and were quite cheap at under 12 USD incl. 25% VAT & delivery.

author: nctnico
author_rank: Super Contributor
timestamp: January 13, 2024, 07:18:45 pm
content: Now test the power rating using a DC power supply... See if they hold up. The fact the sticker is restricting is much of the airflow, doesn't look good to me.

author: DaneLaw
author_rank: Frequent Contributor
timestamp: January 13, 2024, 07:38:06 pm
content: The somewhat beefy silver 5W unit works fine with 5 to 7 watts, from handheld transmistters though gets a little hot after extensive tests, but that goes without saying..- the small -40db 13Ghz jobby, Im not even gonna try to challenge its powerrating, its small... its not its questionable 5W power rating that appeals, more if it's linear a good part up in these higher frequencies, as most relative cheap attenuators drops of quite fast.

author: mojoe
author_rank: Frequent Contributor
timestamp: January 14, 2024, 06:16:01 am
content: I just received a Becen 50 W, 50 dB attenuator. It's rated to 3 GHz. First thing, I checked it on my Lite VNA. Yes, it is 50 dB +/-1 dB or less out to 3 GHz. However, the return loss gets progressively worse past 500-600 MHz, and goes to hell above 1 GHz.For my needs, this is OK. I doubt I'll ever need a high wattage attenuator at those higher frequencies.As for the 2 W attenuators, see my other post in this section. They fair much better.

author: Randy222
author_rank: Frequent Contributor
timestamp: January 15, 2024, 10:19:56 pm
content: There are two main specs you should ask from any maker of this stuff.VSWR chartDC ohms test to nearest 1mOhmActual power handling is gonna be a crap-shoot unless vendor actually specs out a DC power level point where the thing burns out or has some level of degradation.If the unit says 0-3GHz and the VSWR goes higher than 1.5, garbage. Good stuff should stay around 1.2 (or lower) in the specified range.If VSWR is 1.2 up to ~500MHz and you'll be under 500MHz, then perhaps you lable it "0-500MHz", but don't expect the little 10w item to handle continuous 10w.

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: January 15, 2024, 10:30:19 pm
content: Generally cheap SMA attenuators tend to have a better return loss measurement than cheap N types. Being physically small, SMA types tend to have a better specification in terms of matching/return loss. I have bought eBay (Chinese) SMA attenuators and had no issues with them up to the limit of my test gear (3 GHz).SJ