Author Archives: matt

ARRL FD 2022

Not too shabby for 5W output power… all but one contact at the very end was made using FT8. I setup on the deck and used temporary antennas. Started out with the hamsticks, but ended up going to the 40M EFHW.

First uBITX QSO

Just had my first QSO on the uBITX! Got a 53 signal report from Buescher State Park, southeast of Austin, TX. 984 miles. I don’t know my exact power output, but the uBITX maxes out at 10W on 80M, on 20M I was probably at about 4W output power.

Tuning up the hamsticks

I spent a few hours this evening with my NanoVNA plugged into a DIY hamstick dipole mount on top of my 8-23′ painter poll.

Several years ago I picked up pairs of hamsticks for 40, 20, 17, 15, 12, and 10 meters. The goal at the time was to use them in a dipole configuration, I got the 40M and 20M sticks sort of tuned a while back… but had not done anything with them for a while.

So… I broke out the NanoVNA, set it up for SWR and Smith Chart and tuned up the hamsticks. Screenshots are from the NanoVNA itself, saved to a microSD card.

While a NanoVNA is not REQUIRED ham radio gear, it’s going to be recommended by me for most hams that express even a passing interest in making or tuning antennas.

Something that I was NOT expecting, was the measurements that I ended up with for the “stingers” on my hamsticks.

40M and 10M both came out to 40 inches.

20M and 15M both came out to 38 inches.

17M is 43″, and 12M is 31″.

So now I am tempted to take two sets of stingers and change them, so that I would have them pre-measured for 38, 39, 40, and 41 inches. That would be most useful for the 40M sticks, which have the narrowest bandwidth, because I could move the best resonant frequency around by swapping stingers without having to loosen the itty bitty set screws.

Most people who are not hams are probably NOT going to get much out of the attached screenshots, that’s fine.

The Pico Pedal

One of the projects that I have been meaning to work on for a while is a foot pedal to use with discord, which for those that are not aware is a text and voice communications application. Most of the time when I am using discord for voice communications, I don’t really want to be using a push-to-talk key to be able to talk to people, mostly because I’m usually busy pushing other keys on the keyboard. My original plan was to use an arduino, but then I found out about the RaspberryPi Pico.

The appealing thing to me about the Pico is that it can run python code. So I ordered a couple of Picos, snagged a generic footswitch off of amazon, and waited for the parts to arrive.

Since I don’t have anything to use as a case currently, I soldered the two wires directly to the board, and then used some string through the mounting holes to secure the board to the end of the cord from the pedal.

picopedal_resize.jpg

The code was pretty simple after reading the documentation for the adafruit_hid library. Whenever I use the footswitch, it sends the keypress for the menu, or application, key.

EDIT 2021-09-29: Discord wouldn’t let me use the Keycode.APPLICATION anymore, so after some trial and error I was able to use Keycode.F24 instead. 

import time
import digitalio
import board
import usb_hid
from adafruit_hid.keyboard import Keyboard
from adafruit_hid.keyboard import Keycode

keyboard = Keyboard(usb_hid.devices)
led = digitalio.DigitalInOut(board.GP25)
led.direction = digitalio.Direction.OUTPUT

led.value = False

foot_switch = digitalio.DigitalInOut(board.GP0)
foot_switch.direction = digitalio.Direction.INPUT
foot_switch.pull = digitalio.Pull.DOWN

while True:
    if foot_switch.value:
    led.value = True
    # keyboard.press(Keycode.APPLICATION)
    keyboard.press(Keycode.F24)
else:
    # keyboard.release(Keycode.APPLICATION)
    keyboard.release(Keycode.F24)
    led.value = False
time.sleep(0.1)