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I think it makes a worthwhile improvement. But... If the signal levels re too high, the amplifier will produce IMD, so it's a trade between the best Signal to Noise Performance and unwanted spurious

Hi Martin, Thanks for the useful tips. As the thick tube may rip off the narrow PCB trace, I will replace the tiny plate with a 1m long wire. Is 1m sufficient to result in a noticeable

The choice of inductor will depend upon the plate capacitance, input capacitance and inductor self resonance. Without a series resistor, it will have a sharp peak, which is not desirable. I don't

Hi Dan, Indeed, Q1 is marked “ MR? ” - the suffix indicating the reverse formed version of BF998. On the other hand, the PCB footprint is intended for the normal formed version. Hi

Hi Chin-Leong Lim, The reason for the peak in gain at HF is the incorrect choice of input inductor. It should have a series resistor, and an inductance value to produce a suitably damped LPF

Yes, very poor quality control.? They likely substituted a component with reversed pinout (e.g. BF998R....note the "R") for the original one (e.g. BF998) thinking it was the same.? Both components

Hi Simon, I bought a PA0NHC clone for ~USD2 from a China vendor (photo below). The price includes the biastee. Both mini-whip and biastee are fully surface mount and the build quality is very good.

Read the two links I posted earlier. https://www.pa3fwm.nl/technotes/tn07.html https://www.pa3fwm.nl/technotes/tn09d.html It does need an "earth" "ground" or some other return path, and it's better

When I tried out my Miniwhips they were mounted on a bamboo cane tied to a garden stake mounted at the corner of my shed. The earth wire ran straight down the pole to a copper pipe driven into the

My understanding is that yes it will work but the noise floor would be very high.

It doesn’t necessarily need an Earth To work good.

I have used the Bonito range of miniwhips for something very similar. Basically I have 2 loops mounted orthoganally in an L shape with the mini whips mounted where the 2 lines of the L meet. Then

It's not too difficult to build one of these yourself, but the output transistor used in the original PA0RDT design is obsolete and any on e-bay or AliExpress at reasonable prices are likely to be

You need to take precautions with a Mini-Whip installation, to get the best from it. https://www.pa3fwm.nl/technotes/tn07.html https://www.pa3fwm.nl/technotes/tn09d.html Regards, Martin

Build Your own.

Thank you! Simon <nigel_clayton@...> wrote:

Here is a link (not sure if still valid) roelof@...

Hi, I've read a lot about those but where I can purchase them? Thanks, Simon <nigel_clayton@...> wrote:

I use PA0RDT mini whips in two locations together with other receive only loops that can be phased one against the other. I suggest using original PA0RDT not Chinese copies!

Hi everyone, Thank you, Simon KM6MUL