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Hi Sigi Yes they work well. As long as can get bottom leg clear of gnd. But abit impractical for low bands. Ie 40m high for 80m Simon

Hi Chin-Leong, That's interesting, was that the circuit you came up with after our previous discussions about how best to simulate a loop in the absence of a standard method ? I have uploaded my

Recently, I have assembled several LZ1AQ preamps on FR4 1.5mm 2-sided PCB. In the album below, you can find the photos of the assembled preamps, graph of measured and modeled gain, photo of dummy

The list does not allow attachments. Please upload to the Files area, and please include a descriptive folder name and file names. Think about the people who may see these files 2 years from

I could not install a massive radialfield on my property so i searched a different solution ... result is a vertical dipole (so its "earthless") with endloading on both ends a longer endloading at

The following photos have been uploaded to the 9W2LC's LZ1AQ amp ( /g/loopantennas/album?id=296366 ) photo album of the [email protected] group. * dummy_Z--f_sim--g8jnj

biastee@... updated the photo album 9W2LC's LZ1AQ amp ( /g/loopantennas/album?id=296366 )

biastee@... added the photo album 9W2LC's LZ1AQ amp ( /g/loopantennas/album?id=296366 )

FYI Infineon AN 024 "Parasitic Capacitance in Bipo lar Junction Transistors" (

I can support this observation from my own experience with some higher fT Transistors. I believe the lower junction capacitances and feedback capacitances of newer generation bipolar processes are one

Caaarlo, Would you publish as attachments complete s1p files for both amplifier and your loop antenna ? I am planning to check whether an impedance matching network can be synthesized for this

The output transformer is now the limiting factor for 30 MHz high end gain. The 2SC5551 is much less susceptible to UHF oscillation than many other such transistors, though some circuits using it

The ft of the 2SC5551 is 3.5 GHz. This should show absolutely no gain slump at 30 MHz. But,being in the GHz range, it will be far more difficult to "tame". Good ?W layout techniques will be

Look up "gain-bandwidth product".?? This amp has about +25 dB gain. If it had 0 dB gain then it could work at its rated max frequency. 73, Steve AA7U

Ok, I stand corrected, as I was doing things wrong, both maths and sweep: 1-The VNA was being saturated with 10dB above its dynamic range. 2-THe mismatch attenuation calculations were wrong, so the

The ft of the '2222 is 250 to 300 MHz. How could that account for gain slump at 30 MHz? Dave - W?LEV [email protected]> wrote:

The following photos have been uploaded to the Caaarlo LZ1AQ sweep ( /g/loopantennas/album?id=296346 ) photo album of the [email protected] group. *

Thanks to Caaarlo for pointing out my long input lead problem. I've redone the MPS2222 build plus built a second one using 2SC5551. I've deleted the old picture and sweeps from the folder and put new

Ideally, but when using a stand alone VNA, that is not connected to anything, it is so small in terms of wavelength, that it is effectively "floating" and balanced without the need for an extra

Mine is around +23dBm I also tried varying the sweep power, no significant changes noticed up to the maximum level of 0dBm. Regards, Martin