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Chinese connectors N-SMA , 23 January tropo

Last microwave meeting Heelweg, 


I wanted to test my 23cm LNA  MMC SKY67151
https://vhfdesign.com/lna/lna-23cm-sky67151.html
Like picture below but N connector version .
The older type below has a bandpass 100MHz / -3db  exellent results low noise
high gain no self oscillation no more 4G interference.
The newer type has 20MHz bandpass a HAM friend wanted my old to use it for 23 ATV
And i got a new in return
Needed   N-SMA adapters since my tiny XVTR box at the dish uses SMA type relay
The pre-amp / XVTR is direct at the dish.
I got 2 "Chinese" N-SMA with it
The measure crew at the noise figure stand told me right away you can throw this N-SMA in the bin...
But please measure first and judge then..
It was found that the suspect adapter is not bad at all
 adding about only 0.1dB to the noise figure.
That is a normal insertion loss for a connector.
A brand adapter Amphenol  offered 10€ used but gave no less noise then the suspect.
Then another brand type was found Telegärtner, new the seller accepted 2€
That one was just marginal better.
The noise figure found  little over 0.4dB
Already tested a lot of this LNA's by those men but non reached the 0.3dB n/f .
Some one told me  his LNA was measured 0.3 but at an other measuring setup.
Could be this measurement was conservative... like my own power measurement.
Anyway the cheep eBay connector was as good as Amphenol in this setup.

The newer LNA was tested last week during a period of good tropo  23 January
heard 1296.890 OK0EB
1296.970 OK0EKL  also 24 Jan.  and 1296.827 SR6LHZ  1W  beacon on excellent high locations
no human OK SP heard
Also new active strong beacon is 1296.875 ON0VHF
some DL beacons very loud  1296950.8 DB0GW s9
and a new heard 1296.880 DB0MOT JN40ff
Tropo was selective only S-E QTF

After the week with good tropo the weather changed to normal showers and more wind.
Still i can hear DB0GW weak  a sort of receive Benchmark for me.
It seems beter then or at least the same as before with the first LNA.
But now it seems we change to more winter weather type and 23cm can be put down again.





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