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Looking at the AliExpress pictures, it would seem to use a Qorvo TQP3M903 700 - 6000 MHz Ultra Low Noise, High Linearity Low Noise Amplifier

https://www.qorvo.com/products/p/TQP3M9037

Although many devices of this type can operate outside their specified parameters, it is difficult to tell how well this may work, without testing one in a specific application.

In this case, I suspect the IMD performance degrades outside the specified frequency range, and may not be adequate at short wave frequencies. I have used similar devices as the basis of an active antenna, but they easily overload if connected to anything other than a very small antenna element.

It's tricky to find a cheap commercial amplifier that has adequate performance to use ahead of the KiWi. I build my own design of RF distribution amplifier, and it was quite an undertaking to achieve decent IMD performance on the LF bands, whilst still having a good noise figure on the HF bands. In the end I used two separate amplifier chains, with diplexing filters to split the frequency ranges, but it is still barely adequate when connected to a decent antenna.

Regards,

Martin

I'd suggest checking your power supply, as an initial part of any investigation..

I've had similar problems, and it's nearly always turned out to be power supply related.

On particular problem is poor quality electrolytic capacitors that "dry" out over time, and the power supply smoothing and regulation suffer as a result. This is not always immediately obvious, but sometimes becomes more apparent when the KiWi and Beagle draw more current during certain operations.

Regards,

Martin

Broadband loops don't have to be mounted that high above the ground. 2m is about the optimum, and my loops are actually ground mounted in among some bushes.

The key thing is to get them as far away as possible from potential noise sources. They don't significantly interact with nearby objects, which means that you can often locate them in spots that would not be suitable for other types of antenna.

In addition, you can rotate them so that local noise sources are nulled out, and moving them slightly can help ensure that the null does not fall in a desired direction.

Keep experimenting until you can't easily obtain further improvements.

Regards,

Martin

Hi,

Yes, for a single loop connected as "A" connect pins 3 & 6 together.

You don't need to use V1, V2 & Ground for a loop, those are only required if you wish to use a separate pair of dipole elements.

BTW The thing that catches many people out, is mentioned in the two notes highlighted at the beginning of the instructions.

IMPORTANT !

The Control board must be with removed jumpers J5, J6. Connect to J2 the mode control switches. Connect the PS output to J7. Be sure that the green LED is ON. That means that the polarity connection is right.

The Amplifier board should be with removed jumper J6. Connect the two boards with FTP cable crimped by the user. Be sure that the green LED on the amplifier board is ON. That means that the PS connection is right.

It is a very versatile amplifier with lots of options you can try, but as you have discovered, it can sometimes be tricky to ensure that you have selected the correct jumper configurations.

Good luck,

Martin