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Notes for Science-1A at Clovis College


Notes for Physics-10 for Fall 2018 at Clovis College

Notes for Raspberry Pi ACM Student Workshop at Clovis Community College

In this one-month workshop, we configured a Raspberry Pi as a WiFi access point and demonstrated how it can control stepping motors and other hardware. Most students bought a CanaKit Raspberry Pi 2 Ultimate Starter Kit. For $8 each, I supplied baggies with additional LEDs, a ATMega328P processor, and a couple other components so that they could upload and run ATMega328P assembly programs from their Pi. These files give all the details.

Art by Marren Butler (my wife)

Physics-4A Notes

Kanji-Flash Softworks

Information for Scientists and Engineers who wish to read technical Japanese literature.

View from Glacier Point

This is my favorite picture of Half Dome, Nevada Falls, and Vernal Falls from Glacier Point. I took this on June 15, 2005, during a hike with one of my daughters to Glacier Point from Yosemite Valley via the 4-Mile Trail.

Pictures from a hike up Yosemite's Mt. Hoffman

Mt. Hoffman is located near the center of Yosemite National Park. It is only 10600' high, but, because of its central location, it has one of the most spectacular panorama views in the park. To the South is Glacier Point and Senital Dome above Yosemite Valley, to the SouthEast is Cloud's Rest, Half Dome, and in the distance Mt. Clark and other peaks of Yosemite's southeast corner. To the East is Lake Tanaya, Cathedral Peak, Tuoloumne Meadows, and the peaks from Mt. Dana to Mt. Lyle. More peaks and valleys are visible as one turns from the northeast to the southwest.

A trip up Half Dome

Here are pictures and a description of a hike to the top of Half Dome starting from the Sentinel Dome parking lot.

Trail to Cloud's Rest

The Cloud's Rest trail from Tenaya Lake is described here with a Table of elevation changes.

Mt. Dana in Yosemite National Park

Next to Tioga Pass at the east end of Yosemite National Park is Mt. Dana. From its 13061-foot high summit, one can take in a spectacular 360-degree view with Mono Lake to the East, Tuoluomne Meadows to the West, and the Sierra Crest to the North and South.

Opening Day for Tioga Pass in 2008

We took a drive over Tioga Pass on May 22, 2008, to see the remaining snow, visit Mono Lake, eat at the Mono Cone, and drive the June Lake loop. These are some of our pictures.

Hike to Bennettville and to the lakes of Mine Creek

This easy hike takes one up to what is left of a mining boom town, and a series of meadows and lakes heading toward Mt. Conness.

Chilnualna Falls trail

The Chilnualna Falls trail near Wawona is a great hike for the early spring or late fall when the higher trails are unavailable.

Sierra Foothills Ranch Flora and Fauna

A collection of pictures showing the ranch flora and fauna and our surrounding gardens.

Reducing Our Energy Use by 50%

By using well-known techniques, we reduced our ranch energy consumption by 50% without sacrificing quality of life. The repair history for our 2003 prius may also be useful.

SOLO - Sequoia Organization of Llama Owners

The web site of a group of llama-owning hikers who go on monthly trips into the Sierra Nevada mountains.

Two examples of using a polarizing filter in photography

When the sun is at your back, the blue sky up ahead of you is largely horizontally polarized. Using a vertical polarizing filter makes it darker and lets the trees and clouds stand out better. Similarly, when sunlight reflects off of water, it is also largely horizontally polarized. Using a vertical polarizing filter then blocks out the reflection and lets you see into the water. This picture shows these effects.

Useful Links for Voters

A collection of links I recommend for voters in the 2008 presidential election.

Configuring a $200 Walmart TC2512 Linux PC for use when teaching Linux.

I needed an inexpensive PC to use when I teach Linux at Los Angeles City College Community Services. The classes install Ubuntu Linux, do networking games, compile a custom kernel, set up a full range of servers (DHCP, DNS, Apache, vsFTP, SSH, CUPS, Samba, SMTP, POP3, IMAP, and Mail list), and demonstrate a Web Database Application using MySQL and PHP. The Walmart TC 2512 comes with gOS system which I replaced with Kubuntu 8.04, 512 MB which I augmented to 1.5 GB, and a single ethernet interface to which I added another. Total cost $250 (plus tax and shipping).

Configuring a $200 Walmart TC2502 Linux PC for my brother.

This very low-cost PC is an excellent computer for folks who just want e-mail, web browsing, word processing, printing, and digital camera interfacing. It can, however, do far more. Here are instructions for setting it up with Ubuntu and for dealing with its unsupported modem.

Solving Ubuntu Screen Resolution Problems

Ubuntu has little difficulty configuring screen resolution on display hardware that automatically reports its capabilities using the DDC and EDID protocols, but older hardware needs special care. These notes are designed to help new Ubuntu-10.04 users get the expected resolution from their older hardware.

Booting Linux

A summary of a talk given to the San Gabriel Linux Users' Group about the Linux Boot Process and how to make boot diskettes and boot CDs. This info is dated, but folks seem to still find it useful.

Creating and Using a Linux File Containing an AES Encrypted Filesystem

This note shows how to create a safe place to put important information that won't be compromised even if your computer is stolen.


A program that helps explain the purposes of various files in the linux system. It is gradually becoming obsolete since I have not had the time to keep its database up to date.

Book List

A list of good non-fiction books I have enjoyed reading over the past few years

Mavica CD500 Camera at High Altitudes

Details of an altitude problem discovered when using my Mavica CD500 camera at altitudes above about 11,000 feet.

Some Electronics Projects

Electronics has changed considerably since my days with vacuum-tubes, and every few years I get the urge to build some electronic gadgets using the latest technology. I will add projects to this list as they reach a presentable stage.

USB-Driven Electronics Using Open Source Linux Software

A summary of an August 8, 2007, presentation given to the Fresno Open Source Users Group (FOSUG) that describes how I am connecting electronic gadgets to my computer using a USB connection and interfaces from DLP Design. The Linux software is described and all C and assembly code is linked.

Last updated: May 9, 2022

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