Resonant Speakers for CW

Resonant Speakers for CW


1. http://kd1jv.qrpradio.com/resonatespkr/CWSPKR.HTM

2. http://www.n5ese.com/res_spkr.htm
a. http://www.n5ese.com/res_spkr_sketch.jpg
  b. http://www.n5ese.com/res_spkr_parts_med.jpg

3. http://www.qsl.net/n5iw/RESONANT.htm

4. http://www.n5ese.com/res_spkr_sketch.jpg

5. http://www.n5ese.com/res_spkr_parts_med.jpg

ZL1CVD, Chris Day, CatDisplay

ZL1CVD, Chris Day,  CatDisplay

Works with Yaesu FT-817, FT817ND, FT-857, FT-857D, FT-897 & FT-897D transceivers.

https://sites.google.com/site/zl1cvd/catdisplay

Rig Expert AA30.uno SWR and Antenna Analyzer Kit

The Rig Expert AA30.uno has been available since, it appears, November 2017

I hadn't seen it before. It is essentially the AA-30 analyzer w/o the case and is supplied as a partial assembly kit.
It can be connected to a PC and can be intyerface to Rig Experts AntScope program.

It can easily be interfaced and controlled by an Arduino CPU. That makes it possible to make all sorts of wireless and remote controlled instruments.

Looks like it can be had for approximatley $80 depending on the vendor.


https://rigexpert.com/news/see-the-aa-30-zero-video-review/

https://rigexpert.com/products/kits-analyzers/aa-30-zero/

Frequency counter using F{GA, STM32 and a Bluetooth Android APP

NANOCOUNTER Frequency counter using F{GA, STM32 and a Bluetooth Android APP

This is from a blog posy Andy's Workshop

I like the idea pof instruments that use a tablet with Bluetooth interface for data display and instrument setup.


http://andybrown.me.uk/2016/02/21/nanocounter

A RUGGEDIZED GENERAL PURPOSE 100 kHz - 2 GHz LOW NOISE RF PREAMPLIFIER by Glen E. Gardner Jr., AA8C

As submitted to QEX/Quarterly Communications for Publication
Published in May-June 2004 QEX

A RUGGEDIZED GENERAL PURPOSE 100KHz-2GHz LOW NOISE RF PREAMPLIFIER
by Glen E. Gardner Jr., AA8C

http://gridtoys.com/preamp/preamp.html

A JFET preamplifer for 50 MHz by AA8C

A JFET preamplifier for 50 MHz
Glen Gardner, AA8C
http://gridtoys.com/6m_preamp/jfet_preamp.html

Possible Replacement for MPF-102/MPF-105 JFET

Possible Replacement for MPF-102/MPF-105 JFET

http://gridtoys.com/6m_preamp/MMBF5457.pdf

https://www.onsemi.com/pub/Collateral/2N5457-D.PDF

Aluminum 40/30/20 meter Square Loop Antenna by AA8C

A MORE EFFICIENT MAGNETIC LOOP ANTENNA

Variations on a Theme Continued

Glen E. Gardner, Jr.

AA8C

http://gridtoys.com/glen/loop/loop3.html

Early 20th Century Magazines and Engineering Proceedings

A very large collection of early 20th century radio magazines and proceedings in pdf format.

http://www.jumpjet.info/#menu

40/80M Direct Conversion REceiver by F6KFT

The "TENOR" receiver 40 / 80m Direct conversion receiver by F6KFT

http://f6kft.free.fr/spip.php?article31