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eschen42 / BalancedDipole_10m-20m.md
Last active July 6, 2025 03:50
Broadband 10m–20m Balanced Dipole with Z-Match ATU

Broadband 10m–20m Balanced Dipole with Z-Match ATU

This is my lightly edited dialog with Microsoft Copilot. Initially, I ran "Deep Research" against the first prompt.

1. Prompt for Broadband 10m–20m Balanced Dipole with Z-Match ATU

I want to create an electrical schematic for a broad band (10m - 20m) balanced amateur radio antenna with a balanced feed line that is connected to the transceiver at via a Z-match antenna tuner unit (ATU).

  • There will be two 50 foot long LMR 240 coax cables whose cores ("C+" and "C-") will feed two the two antenna radiators ("R+" and "R-", each 29 ft long and horizontal, oriented anti-parallel to one another, fed at the "proximal" end with no connection at the "distal" end).
  • Label the ends of coax as "T" for transciever and "A" for antenna.
@eschen42
eschen42 / whisker_dipole.md
Last active July 5, 2025 18:46
Folded dipole for 20, 17, 15, 12, 11, and 10 meters

ABANDONED DESIGN! please ignore (or laugh)

Design of a 10.20 m Center-Fed Folded Dipole with Shunt-Connected Open Stubs

This is a discussion of designing a multiband trapless low-SWR antenna for the upper HF amateur radio bands. Responses are from Microsoft Copilot <https://copilot.microsoft.com>.

**Design an 10.2 meter center fed folded dipole antenna for the 20m (14.0-14.35 MHz), 17m (18.068-18.168 MHz), 15m (21.0-21.45 MHz), 12m (24.89-24.99 MHz), 11m (26.96-27.41 MHz), and 10m (28.0-29.7 MHz) amateur radio bands using a 20 gauge silicone insulated antenna wire with a 1.8mm outside diameter, fed by a 200 ohm balanced feedline. For each band, show the expected ranges of SWRs and impedances, and break down each impedance into its reactive and resistive components. To minimize the SWRs, design symmetrical open circuit stubs that are shunt-connected at the feedpoint and each composed of two identical lengths of antenna wire; add three stubs to the design to redu

@eschen42
eschen42 / ulogd2sql.icn
Created October 22, 2024 15:04
Parse ulogd syslog lines to SQLite insertion statements
#!/usr/local/bin/icon
############################################################################
#
# File: ulogd2sql.icn
#
# Subject: Parse ulogd syslog lines to SQLite insertion statements
#
# Author: Art Eschenlauer, adapted from rough-in by Microsoft Copilot
#
# LCTboot_inspect - TestCor::LCTboot modified:
# - to return a "reportables" data.frame as an attribute of the result
# - (for estimating the adjusted and unadjusted p-values)
# - to return the function environment as an attribute of the result
# - (for debugging reportables)
# - to use the normal approximation when Nboot == 0
# - (so that the same code base may be used for LCT-N and LCT-B)
# ref: https://github.com/cran/TestCor/blob/9d5d2a9a1ac284e3346bd144776559cbd82a8b52/R/FdrMethods.R
#' Bootstrap procedure LCT-B proposed by Cai & Liu (2016) for correlation testing.
#'
@eschen42
eschen42 / wsl2-reset.md
Created October 21, 2022 07:58 — forked from kiransubash/wsl2-reset.md
Reset WSL2 networking on windows 10

Open Powershell or Cmd as Administrator and run the following commands

wsl --shutdown
netsh winsock reset
netsh int ip reset all
netsh winhttp reset proxy
ipconfig /flushdns
@eschen42
eschen42 / co_ject.icn
Created October 7, 2022 20:30
simple "co-expressions as objects" prototype
procedure co_foo(state, args[])
return .(state[args[1]] +:= args[2])
end
procedure co_new()
local state, foo, msg
state := table()
state["something"] := 1
@(
foo := create (
@eschen42
eschen42 / pingstat.icn
Last active August 21, 2022 20:37
pingstat.icn - compute statistics for unix ping output
#!/bin/env icon
############################################################################
#
# File: pingstat.icn
#
# Subject: pingstat.icn - compute statistics for unix ping output
#
# Author: Arthur Eschenlauer (https://orcid.org/0000-0002-2882-0508)
#
# Date: 21 August, 2022
@eschen42
eschen42 / header.icn
Last active August 21, 2022 20:26
Icon standard header
############################################################################
#
# File: [progname].icn
#
# Subject: [progname].icn - [subtitle succinctly describing what progname.icn is or does]
#
# Author: Arthur Eschenlauer (https://orcid.org/0000-0002-2882-0508)
#
# Date: [e.g. 26 March, 2020]
#
@eschen42
eschen42 / fgrep.R
Created August 8, 2022 21:40
Emulate fgrep in R, i.e., is any of needles found in any of haystacks
#' Emulate fgrep, i.e., is any of needles found in any of haystacks
#'
#' This should perform adequately for a few needles.
#'
#' If performance for many needles is inadequate, use
#' `0 < length(AhoCorasickTrie::AhoCorasickSearch(needles, haystacks)[[1]])`
#' as the implementation for a more realistic emulation of fgrep.
#'
#' @param needles A character vector of length 1 or more
#' @param search_strings A character of length 1 or more
@eschen42
eschen42 / staque.R
Last active September 29, 2022 18:22
staque.R - Icon-oriented stack and queue operations
# staque.R - Icon-oriented stack and queue operations
# - queue:
# - sq_push/sq_pull to pass values thru vector left-to-right;
# - sq_put/sq_pop to pass values thru vector right-to-left.
# - stack:
# - sq_push/sq_get to left end of vector;
# - this is an "upward-growing stack";
# - in Icon, get is a synonym for pop; however base::get exists in R.
# - sq_put/sq_pull to right end of vector;
# - this is a "downward-growing stack".