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MeshCore Repeater Setup

Sun, 02 Aug 2026 00:00:00 +0000

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SenseCAP Solar Node P1-Pro
Heltec MeshTower V2

Repeater Settings

These are specific to the CT Mesh, particularly the 2-byte path hash (important!).

Setting	Value
Public key (optional)	generate a custom 4-digit hex prefix, if desired
Name	set
Latitude & longitude	set
Admin password	set
Guest password	leave blank
Radio settings	`USA/Canada`
TX Power (dBm)	`22`
Advanced > Path hash mode	`2-byte (1)`

SenseCAP Solar Node P1-Pro

Flashing
1. Go to https://meshcore.io/flasher
2. Search for “Seeed Studio SenseCAP Solar”
3. Select “Repeater”
4. Connect USB-C
5. Click “Enter DFU mode”, select USB serial device, wait for checkmark on button
6. Click “Flash!” and wait for completion
Settings
1. Bring up repeater settings page, either:
  1. After flashing, click “Configure via USB”
  2. Go to https://meshcore.io/flasher and click “Repeater Setup”
2. Click “Connect”, select device
3. Apply settings from the table, above
4. Click “Save settings”

Heltec MeshTower V2

[Complete Docs]

August 2026

Sat, 01 Aug 2026 00:00:00 +0000

Work

I am currently splitting time between Remote Ham Radio and TRMNL.

At RHR, the migration from Flex to Icom radios continues. 26 down, 32 to go. Not a lot else to report - it’s business as usual.

At TRMNL, work continues to streamline the firmware development process. The number of open PRs is steadily declining, particularly the open-source contributions from our users. There have been some bumps along the way, but that’s expected with a faster release cadence. Things will improve over time, especially now that I have some free time to begin shoring up code quality.

July 2026

Fri, 10 Jul 2026 17:05:39 -0400

Worked

I’m currently splitting my time between Remote Ham Radio and TRMNL.

At RHR, we focused on shoring up the Icom radio transition - fixing bugs, improving speed and reliability, and so on. We have 15 radios live in the field now.

At TRMNL, I have transitioned my work to primarily on firmware. My main goal right now is to improve our firmware release cadence by adopting new branching and release strategies, being proactive about triaging new issues and PRs, and just trying to stay unblocked in general. Some days of wrangling branches feel like a huge time sink with not a lot accomplished, but the effort is paying off, and things are continuing to improve. Soon, we wil be able to focus more on refactoring to take better advantage of OOP principles and reduce merge conflicts.

Classic Mac resources

Sun, 14 Jun 2026 00:00:00 +0000

Favorite System 6 software

Wallops - modern (!) IRC client
NCSA Telnet 2.x - for BBSes and ham radio DX clusters
Fetch - FTP client

Development

Repairs & Maintenance

Information

Accessories & Hardware

Software

Disk formats

SS/DD is a 400k disk
DS/DD is an 800k disk
According to this page, some later floppies were marked as as SS when they were actually DS media, so that would explain why they are showing up as 800K

Installing MacTCP and DaynaPORT on System 6 on Mac Plus

Based on the official guide.

Flying

Sun, 14 Jun 2026 00:00:00 +0000

I’m a licensed Private Pilot, and co-owner of a 1977 Piper Archer II.

Hosting AIM & ICQ

Sun, 14 Jun 2026 00:00:00 +0000

Server setup

retro-aim-server - Installation instructions

Set up DNS
Configure settings.env
1. Set API_HOST and OSCAR_HOST to hostname
Open TCP ports 5190-5197 in firewall

Creating systemd service

As root:

$ vim /etc/systemd/system/retro_aim_server.service # contents below!
$ systemctl daemon-reload
$ systemctl enable retro_aim_server.service
$ systemctl start retro_aim_server.service

# Verify it's running
$ systemctl status retro_aim_server.service

# Logs (-f to follow)
$ journalctl -u retro_aim_server.service

Contents of /etc/systemd/system/retro_aim_server.service:

[Unit]
Description=Retro AIM Server
After=network.target

[Service]
ExecStart=/root/retro_aim_server/retro_aim_server
WorkingDirectory=/root/retro_aim_server
Restart=always
User=root

[Install]
WantedBy=multi-user.target

AIM client

AIM client for macOS - version 5.9 is the latest and greatest

Palm OS resources

Sun, 14 Jun 2026 00:00:00 +0000

Emulation

CloudpilotEmu - Web emulator
CloudpilotEmu iOS - iOS emulator
ROMS on PalmDB - for said emulators

Apps

PalmDB - every app you could want

Modern

palm-sync - HotSync drivers in JavaScript
SpringSD - SD card interface for Handspring Visor

Reading and writing HFS floppies

Sun, 14 Jun 2026 00:00:00 +0000

hfsutils manpage :: OS X Daily article

This is a slightly-janky way to copy files to and from HFS-formatted floppies created on System 6 or 7. It works on modern macOS with a USB floppy drive and 1.44 MB disks. 400K and 800K disks don’t work in modern drives.

Setup

Install hfsutils via Homebrew.

brew install hfsutils

You need root access to do anything else beyond this point, so run sudo -s to get a root shell.

Setting up FTP servers and clients

Sun, 14 Jun 2026 00:00:00 +0000

FTP is convenient for vintage computers that are online but do not support SFTP.

FTP clients

Fetch for System 6.x - Mac OS

Set up an FTP server

Disclaimer: FTP is an outdated, insecure protocol on the modern Internet. Use firewall rules to ensure the server only exposed to trusted IP addresses.

This server uses vsftpd.

On Ubuntu:

sudo apt update
sudo apt install vsftpd
adduser # to make a new FTP user

Edit /etc/vsftpd.conf and change:

My development stack

Sat, 13 Jun 2026 00:00:00 +0000

Coding

Visual Studio Code - editor du jour
Gitfox - git GUI client
TablePlus - client for all the databases
iTerm2 - terminal
Claude - a great assistant

Documentation

Obsidian - note-taking, documenting
OmniGraffle - diagramming
CleanShot X - screenshots

Tooling

asdf - runtime management for Ruby, Node, Go, Elixir, etc.
direnv - local environment vars
sse - secrets management

Personal web app hosting

Sat, 13 Jun 2026 00:00:00 +0000

I have a lot of solo side-projects. Many of them are web apps with very modest resource requirements. Managing their deployments isn’t fun. And it’s easy to forget how to do them in the months (or years) between releases.

So here’s my simple, standardized, reproducible, inexpensive playbook for easy deployments.

Hosting

I use DigitalOcean. Linode could work too.

VM: one DigitalOcean Droplet
- 2 GB RAM / 50 GB disk ($12/mo + $3/mo for backups)
Database: SQLite (free)
Storage: DigitalOcean Spaces Object Storage ($5/mo)
Domains and DNS: Hover and DigitalOcean

Secrets

Secret environment variables like API keys are manged by SSE, a tool I wrote to fulfill this exact need.

June 2026

Mon, 01 Jun 2026 00:00:00 +0000

Worked

I’m currently splitting time betwen Remote Ham Radio and TRMNL.

At RHR, the transition from FlexRadio to Icom continues at full steam. As of today, 14 stations have been migrated, with 39 to go. It sounds like a lot, but it’s going quickly. Check back next month.

Integration with third-party hardware and software continues to be a pain point. Users want to connect their native applications and physical devices to RHR, but of course we are sandboxed in the browser, which limits our connectivity options. Luckily Web Serial and Web MIDI APIs have come a long way recently (Firefox just added WebSerial this month!), enabling us to integrate whole classes of hardware controllers without any external dependencies.

May 2026

Fri, 01 May 2026 00:00:00 +0000

Worked

I’m currently splitting time betwen Remote Ham Radio and TRMNL.

At RHR, we began rolling out Icom radio to our stations. This includes the IC-7300MK2, IC-7610, and IC-9700. As a collection, these models will enable us to easily cover all bands from 160m through 23cm. The biggest unknowns and challenges so far have been related to integrating with external hardware like amplifiers and tuners, but we haven’t found any show-stoppers yet. We started the business with the Elecraft K3 in 2012, transitioned to Flex Radio in 2019, and we’d like to finish this latest transition by the end of 2026. I guess these things come every seven years. Like cicadas? Anyway, check back in 2033.

April 2026

Wed, 01 Apr 2026 00:00:00 +0000

Work

I’m currently splitting time betwen Remote Ham Radio and TRMNL.

At RHR, we’re focusing on application and hardware stability. This involves a lot of deep-dive bug fixes and stripping down existing functionality to the core features that people actually use.

We had a week-long TRMNL company retreat which was an amazing experience. I got to meet my teammates in person for the first time, and all things considered there was a lot of hang-out-and-code-in-the-same-room going on. I even got to use my 3D-printing design skills for something practicable.

March 2026

Sun, 01 Mar 2026 00:00:00 +0000

Work

I’m currently splitting time betwen Remote Ham Radio and TRMNL.

At RHR, the Desecho Island DXpeditino has passed 100,000 contacts in just over a month. It’s been about 50% FT4 and FT8, 30% CW, and 20% phone. Not bad for an unattended station with marginal antennas.

At TRMNL, work continues to prepare to TRMNL X. We are also doing a lot in the BYOD (Bring Your Own Device) space.

Rewriting SOTA Goat in Swift

My iOS app SOTA Goat has been written entirely in Objective-C since its inception in 2012. I didn’t hate that, but it was a barrier that prevented me from actively working on the app. It badly needed updates for iOS 26, plus I wanted to add some features that folks had been requesting for years.

February 2026

Sun, 01 Feb 2026 00:00:00 +0000

Work

I’m currently splitting time betwen Remote Ham Radio and TRMNL.

At RHR, we have been working hard supporting the Desecho Island DXpedition. Over 50,000 contacts have been made from the remotely-controlled station on the uninhabited island. It has solar power, Starlink, and two amateur radio stations with radios and antennas. There’s even a realtime stream of contacts being made.

At TRMNL we’re busy preparing for the launch of the bigger, badder, more capable TRMNL X.

Buddipole

Mon, 01 Jan 0001 00:00:00 +0000

Click on Bricks

Mon, 01 Jan 0001 00:00:00 +0000

See it on The Wayback Machine.

In 1998, I entered the very first-ever ThinkQuest Junior contest as a fifth-grader, on a team with a student from another district.

Our entry, Click On Bricks, taught the basics of multiplication through visualizations of LEGO-style bricks generated from the software Gryphon Bricks.

It was good enough for a fifth-place win in the Mathematics category. I used the cash prize to open up my very first bank account.

Cooking Up a Storm

Mon, 01 Jan 0001 00:00:00 +0000

In 2009 I took part in NOAA’s Ernest F. Hollings Undergraduate Scholarship at the National Weather Center in Norman, OK.

Throughout the summer internship, I created an educational presentation for Science On a Sphere about the formation of supercell thunderstorms.

cultofdone.org

Mon, 01 Jan 0001 00:00:00 +0000

https://cultofdone.org/

The Cult of Done Manifesto has guided me to finish (or destroy (or share on the internet)) projects since its inception in 2009.

The original post from Bre Pettis is gone, and I was never a fan of the updated Medium post and its infographics. I wanted something I was proud to share.

DockYard

Mon, 01 Jan 0001 00:00:00 +0000

As part of the team at DockYard, I consulted with clients to build Phoenix web applications.

Clients included Veeps, Kamana, and others.

Does Not Compute

Mon, 01 Jan 0001 00:00:00 +0000

ESPHome gauge

Mon, 01 Jan 0001 00:00:00 +0000

Converting an analog Western Electric meter to be used as a smart home gauge with ESPHome

Components

NodeMCU ESP32
Hammond 1455C801 enclosure
DC barrels
10k potentiometer
3D-printed panel
3D-printed mounting bracket
Alien Tape

ESPHome config

output:
 - platform: esp32_dac
 pin: GPIO25
 id: dac_output

number:
 - platform: template
 name: "My Gauge"
 optimistic: true
 min_value: 0
 max_value: 100
 step: 1
 set_action:
 lambda: |-
 id(dac_output).set_level(x / 100.0);

Gallery

Internals

Jammed in the enclosure

Mounted to the back of the meter

GBCMR

Mon, 01 Jan 0001 00:00:00 +0000

The Game Boy Camera is a perfect match for TRMNL. They’re both personal, minimal, and - most importantly - 2-bit grayscale.

That’s why I created GBCMR. It fulfills a few goals:

Offload photos directly from Game Boy Camera with GBxCart RW
Create and share photo galleries with your friends
Stream that gallery to TRMNL e-ink displays

Photo Download and Conversion

This is pure JavaScript in the browser. It requires WebSerial support. Chrome, Edge, or related browsers are supported, but not Firefox or Safari.

HeathKit SB-102

Mon, 01 Jan 0001 00:00:00 +0000

Keysight (Agilent)

Mon, 01 Jan 0001 00:00:00 +0000

Lightning Talk - ElixirConf 2017

Mon, 01 Jan 0001 00:00:00 +0000

MacDown

Mon, 01 Jan 0001 00:00:00 +0000

Download

Precompiled packages in various formats are available from the releases page.

Features

Markdown-aware editing of headings, bold/italic, lists, blockquote, etc
Auto todo list toggle for GitHub-style tasks like - [ ] todo
Multi-document support
Integrated file browser for easy navigation between files
Modern keyboard shortcuts for text and window manipulation

Macintosh Classic II

Mon, 01 Jan 0001 00:00:00 +0000

Macintosh SE/30

Mon, 01 Jan 0001 00:00:00 +0000

METAR Map of Florida

Mon, 01 Jan 0001 00:00:00 +0000

METAR Map of the Northeast

Mon, 01 Jan 0001 00:00:00 +0000

I have built two 24x36" maps that display airport weather conditions using individually-addressable LEDs. They are powered by Raspberry Pi Zero W’s running a custom Elixir Nerves application.

They are constructed from MDF with a printed map glued on top. LEDs shine through the map, making it magically come alive when powered on. They also have LDR sensors to automatically dim the LEDs when the room is dark. The frames are custom-made 1x3" stained pine.

Now

Mon, 01 Jan 0001 00:00:00 +0000

This page’s body is ignored — the now template renders the most recent update from /then/ automatically. Add a new month with ./bin/new-now and /now/ follows along on the next build.

PowerBook 180c

Mon, 01 Jan 0001 00:00:00 +0000

PowerBook G3

Mon, 01 Jan 0001 00:00:00 +0000

Remote Ham Radio

Mon, 01 Jan 0001 00:00:00 +0000

RHR KeyMate XIAO

Mon, 01 Jan 0001 00:00:00 +0000

Based on the Seeed Studio XIAO RP2040, the KeyMate acts as USB MIDI interface between Morse code keys and transceivers.

In client mode, it precisely timestamps every key-down and key-up transition, emitting MIDI events in the MoMIDI spec.

In server mode, it use an optoisolator to drive the key input to a radio, accurately reconstructing the timestamped key signals.

schrockwell.com

Mon, 01 Jan 0001 00:00:00 +0000

My personal site at schrockwell.com was rewritten to use the Hugo static site framework.

It adds the concept of “Projects” with unique numeric identifiers and tagged categories.

smellycamp.us

Mon, 01 Jan 0001 00:00:00 +0000

https://smellycamp.us/

Created during my senior year at the University of Connecticut, this app analyzes weather model data to come up with a weekly forecast for the Horse Barn Index (HBI) - a score from 0 to 5 of how stinky the air will be.

A statically-generated site originally written in Ruby, it was rewritten in Go in 2026.

SOTA Goat

Mon, 01 Jan 0001 00:00:00 +0000

SSE - Stupidly Simple Environments

Mon, 01 Jan 0001 00:00:00 +0000

SSE is a highly-opinionated, platform-agnostic tool for managing secret environment variables.

Secrets are saved in an encrypted TOML file that is safe to check into version control. Only the master.key file is required to decrypt and edit it. Multiple environments are supported; development is the default.

SSE draws inspiration from Rails credentials and SOPS. It uses age for encryption.

It’s a single-file executable with no external dependencies, so it’s easy to integrate with development, build, and deployment environments.

SundiaLED

Mon, 01 Jan 0001 00:00:00 +0000

SundiaLED is a linear clock that uses a string of LEDs to indicate sunrise, sunset, and the current position of the sun.

Powered by an Adafruit Feather M0, it uses GPS to automatically determine the sun’s position and length of the day based on the current longitude, latitude, and date.

TODO

Working prototype
Add (or fully convert to) RTC for time (GPS doesn’t always acquire very well indoors…)
Publish source code
Publish basic plans & schematic

Ideas

Maybe a round version, like an actual sundial/clock, makes more sense? Certainly would be easier to find a spot on the wall for it.

TashTalk USB Enclosure

Mon, 01 Jan 0001 00:00:00 +0000

Traffic Light

Mon, 01 Jan 0001 00:00:00 +0000

When I was in high school, my parents bought me a traffic signal for my birthday. Why? I don’t know. But I was determined to do something cool with it.

It was featured on Hackaday (and again) in 2005.

I was also interviewed for a feature in the book Makers by Bob Parks.

A decade later, after purchasing our first house, I added an ultrasonic sensor and converted it to a garage parking assistant.

TRMNL

Mon, 01 Jan 0001 00:00:00 +0000

Woodshop shed

Mon, 01 Jan 0001 00:00:00 +0000