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When regulating Vcc with a zener we automatically insert a simple cap-input Pi network in the Vcc line. I'd check with a scope to determine the before and after noise reduction and to establish the

Zeners are also good noise generators. It could work well, but must be well filtered. Dave - W?LEV [email protected]> wrote: -- *Dave - W?LEV*

Hi All, I saw an interesting article. an amplifier using a 2N5109 at the bottom of this page. https://www.microchem.fr/ayet/atlas/hf_amplifier.html It has a 3.3V zener diode and a 3.3k resistor to

Agreed, and you need 3dB more noise with an actual antenna connected at any specific frequency, in order to ensure that your antenna is constrained by your local noise floor, so a 6dB rise in noise

Just a quick gauge on thermal noise vs. antenna noise: Define (ONLY for the purpose of simplicity) "antenna noise" as the increase in receiver noise experienced by connecting your combination antenna

There is an updated version of John Bryants transformer paper: 2nd look at fabrication transformers for receiving antennas ( https://peditio.net/utility/pdf/bryant2.pdf ) regards, Fred

"Fabricating Impedance Transformers for Receiving Antennas"? is available at IRCA Reprints, #A-155, index at?

https://www.pa0fri.com/Ant/antennes.htm#E ?? Maybe try a different browser. Henry

If anyone is interested, I have several retrofit amps for the Wellbrook ALA1530 loop. They are in a PVC case, and potted. They are a match and fit perfectly on the ALA1530.? ?Everett N4CY

There is a filament known as ASA that is really durable and offers much more UV resistance but it requires a printer that can handle hotter melting temps and has a heated bed.? I have some but have

Diecast aluminum boxes are relatively inexpensive, some can offer waterproofing with an inset gasket, and offer good E-field shielding (if proper attention is paid to ingress/egress of

Thanks for all the suggestions, but I recently purchased an LZ1AQ type amp from Everett instead.? Local waterproof PVC electrical boxes fit the circuit board just right.? I use 1/2 inch Heliax for

Suggestion for KISS method completely DIY.? I thought it was rather difficult to make such a small PCB preamp DIY without a special PCB, so I am just using a 80x80x50mm waterproof electrical box with

can you not find the dimensions online and make some using a 3d printer? Just a though Nick G8SYE

There is a thermodynamic problem embedded in the design a broadband antenna matching network, named "entropy". The issue is well covered

Can't find the links for the ANT articles within there. 73 Horacio CX3BZ [email protected]> escribió:

He was very friendly and I got a mention on his website for fd4 antennas. Rest in peace. -- Thanks Steve M0ZEH

For a broadband transformer the “rule of thumb” is that the reactance of the low impedance winding should be 4x the impedance ?at the lowest frequency of operation. So for a 50 to 450 ohm

I suggest you try The free program TLW which can match using several different methods like L, T, and Pi. /g/nanovna-users/topic/transmission_line_tools/76720904

Why not use SIMNEC 2.5, this versatile tool from AE6TY does the job, including the transmission line and much more. Lots of support and tutorials available. SimNEC Interactive RF-Circuit Analysis (