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Hi Leong, Wow, so I was right, that makes a change :-) It's a common problem, especially with baluns and RF transformers, there are frequently many imperfections in "real life" components, that are

The noise figure? of max 4 dB as specified in the PXT2222A data sheet refers to a frequency of 1 kHz. That says not much about the broadband noise behaviour at HF Frequencies, which is mainly

You may wish to look at the RigExpert AA-55 Zoom. Several people I know find them good for a basic but accurate analyser. I have used a Sark-110 for years and find it excellent simply because of the

It's a pity that low noise, robust, medium ft transistors like 2SC5551a are discontinued. Actively produced BFU590 are low noise and high gain, but need to be treated like a high ft device and lack

Hi Martin, You are right. Placing the balun after the L-network causes problems. ? The simulator showed similar result, regardless of whether the balun is placed BEFORE or AFTER the L-section.

Thank you Tom Anderson SDR_Radio@...

Shape is not that critical, but a circle provides the lowest inductance for a given loop area. The thinker the diameter of the conductor, the better. Regards, Martin

Fred and Andy, Many thanks for your replies and the list of transistors. The last time I bought any RF transistors was a few years ago before Covid and Brexit, when RF transistors and FETs seemed far

Good looking design… I have always heard shape is not that critical in a receive only loop, but that could have been false information. but anyway my real question is how well does it work? What

There is no way to run a proper IMD without a band stop filter that rejects the 2 tones and a band pass filter for each of the tones. ?Everett N4CY

I second that recommendation, old style antenna analysers seem to be very expensive for what they are, and will only provide you with limited data. I have a LiteVNA 64, which was an upgrade from an

Absolutely, it's no good unless you can notch out the fundamental tones. My own notches provide about 40dB rejection, which is just about good enough. Regards, Martin

Why not a NanoVNA of the newer generations? regards Fred

Definitely, but without? notch filters for the original 2-tone signals the tiny-SA will become overloaded. It's own IP3 is about +17 dBm. regards Fred

Hi all not really a loopy question, but after a good cheap antenna analyser for future projects over winter. Have a mfj 259b but after something alittle better.. best regards Simon g0zen

Incidentally, I've just been comparing IMD measurements using a Rigol DSA815 and a TinySA Ultra. I've been using my own test source and notch filters, and providing the notched test tones are kept to

Nice loop, but could you state the loop inductance ? Regards, Martin

Are you selling this as a kit or fully made? Or do you have the plans available?

Very nice loop. 73, Steve

I would like to introduce you to my latest loop. Ideally, a loop should be round, but because the production costs for a round loop with a diameter of 1m are very expensive, I decided to make the loop