How to update a mainboard system BIOS in Linux in a nutshell.

This is just a quick note to help Linux users flash a BIOS upgrade to their system. It’s not a step-by-step so easy your Grandma could do it. Sorry, there’s too many variables to create that. If you’ve ever downloaded and installed Linux via a USB drive this should be just as easy.

If your mainboard BIOS has a built-in utility to upgrade it’s BIOS, use that. It’s the best most foolproof way to go. Visit the website of your MoBo manufacturer for the BIOS update and flashing instructions. Generally all that’s needed is a USB thumb drive formatted to FAT.

If your mainboard does not have a built-in BIOS update feature, check with the manufacturer for options. Unfortunately, many mobo makers assume you have Windows and provide a utility that only runs in Windows or DOS. If you’re setup to dual-boot Linux or Windows, boot into Windows and use their utility. If you’re running Linux only:

1. Download the DOS based BIOS package from your mobo maker. Extract it into a folder of your choice, but keep the name simple as we’ll be using DOS in just a moment.

2. Visit www.freedos.org and download the USB Installer version. Extract it and write the .img file to your USB drive. (hint: use the USB Image Writer utility or Unetbootin)

3. Verify freedos is on your USB drive. You should see autoexec.bat and other DOS looking files. (You may need to reboot your Linux box after initially creating the FreeDOS.)

4. Copy the folder where you extracted the BIOS package onto the FreeDOS USB drive.

5. Reboot the computer and select boot to FreeDOS USB drive.

6. Follow the menus, but don’t choose to install FreeDOS. Instead, exit to DOS.

 

At the C: prompt.

 

7. You should now be at a good old fashioned C: prompt. Change to the folder you made in step 4. Run the executable that starts the DOS based flashing utility. Follow the manufacturer’s instructions.

8. Reboot and confirm you have the new BIOS. You can also verify BIOS version in Linux by using the hardinfo utility or in a terminal type:

sudo dmidecode -s bios-version

That’s all there is to it. Easy as making a bootable floppy but better.

 

FreeDOS also runs in VirtualBox.

 

Side note: FreeDOS also works well in VirtualBox, although I would NOT advise trying to flash your BIOS while running in a virtual environment, best to do that as described above. Good to know if you have some old DOS games you want to run.

 

Enjoy!

  • Kenn Ranous

Vintage Audio Gear – Sony F-81 Microphones

Behold, two fine specimens of early 1970’s Made in Japan Sony F-81 Microphones. A matched set with stands, they sound as good as they look.

 

  • Kenn Ranous

FM Stereo HD Radio Folded Dipole Antenna in a Rugged PVC Radome

Engineered and assembled by me personally, I’m now offering this proven design for sale! Each unit has been individually tested to ensure 100% quality control. This antenna is designed to be installed indoors, in a closet, in an attic, under an eve or patio. Constructed of durable schedule 40 PVC pipe, this is not a fragile antenna subject to easy damage or detuning due to rain. It’s mildly directional perpendicular to it’s length – just enough to help null out interfering stations and multipath signals. Can be installed on a boat, RV or used in the field during your next camping trip.

 

Specifications:

  • Tuned for FM-BC 88-108 MHz reception
  • Full physical size 1/2w folded dipole
  • FM Stereo & HD radio
  • Rugged PVC radome
  • Internal Balun
  • Type F connect (75 ohm)
  • Paintable to match any décor
  • Mounts in any position for best signal
  • Mildly directional perpendicular to length
  • Dimensions: 61″L x ~1″ diameter, tube shaped
  • Range: Up to 100 miles, varies by location/conditions
  • Weight: 1 lbs
  • Mounting clips included
  • Weather Resistant (suggest paint for UV protection if mounted outdoors in sun)
  • Engineered and individually made by hand in Arizona, USA by KA0SBL

 

Antenna for FM HD Radio

Antenna for FM HD Radio

Antenna for FM HD Radio

 

Available for purchase on ebay or contact me for a local demo.

 

Thanks for l00kin!

  • Kenn Ranous

FM-DX and a good LPFM Community Radio Station

I’ve always had a fascination with all things radio including FM-DX. This is where you buy or build high performance FM radio antennas and attempt to receive stations far away. (DX means Long Distance in radio vernacular). In doing so, one expands the palette of stations to choose from. Unfortunately, most radio today is a limited selection of mainstream music and a bombardment of obnoxious commercials. Sure, designing and building a good antenna and getting a far away station is cool, but the content is often a buzz-kill.

Evaluating my antenna designs involves scanning the band with a High Definition radio or SDR and logging signals for comparison. To date my distance record is KUAT in Tucson at 100 miles. Late one recent evening I received a station I never heard before. It was KRWV at 99.3 MHz and although low in signal it was clear. It’s a LPFM 100 watt station in Gold Canyon, Arizona 25 miles away and blocked by several mountains. I checked the FCC coverage map and I’m well outside the predicted range.

This is especially interesting for me because there aren’t many LPFM (Low Power Frequency Modulation) stations around here and snagging one so far away means my latest design works better than expected. I suspect that just enough signal completes the path due to the knife-edge effect. This is when an otherwise line-of-site signal diffracts over or around an obstacle.

As a triple bonus, the format is very good. Arizona needs more radio like KRWV 99.3 The Wave. Their commercials are civilized and not more than 5 minutes per hour. They’re mostly listener supported and don’t do long nag-a-thons. Most importantly is the music they play, a wide variety of smooth jazz, modern jazz, new age, classical and talk. And those are just broad categories, so much of what they play is just good non-mainstream chill music.

You can find them online at:

http://www.goldcanyonpublicradio.org

If you can’t get them on the radio, there’s a live stream at:

http://tunein.com/radio/KRWV-LP-993-s251764/

Thanks for tuning in!

  • Kenn Ranous

 

 

RTL-SDR easy cooling and antenna jack mods

Version 2 of the RTL-SDR dongles came with an aluminum enclosure, a good upgrade from the original. I still noticed it ran hot enough to induce frequency drift as was very warm to the touch. Inside the case, the circuit board has some contact with the case for a heat sink effect but there’s no air flow. And it still has that weird little antenna connection. I de-soldered it from the PCB and enlarged the hole in the case to accommodate a type-F jack. I also added some spacer washers to the end caps to create small slits for air flow. I plugged it into a USB base to maintain a vertical air flow.

 

RTL-SDR mods RTL-SDR mods RTL-SDR mods
It runs much cooler now and frequency does not drift. As an added bonus, the power LED is now visible through the vent slits. The Type-F connectors are durable, available, inexpensive and perform well across the RTL’s frequency range when using RG-6 coax.

 

-Kenn Ranous

Red Rock Country: Oak Creek, Arizona

One of my favorite places in Arizona, Oak Creek near Cathedral Rock. Located just South of Sedona and just West of Village of Oak Creek. Cool, green & shady.

 

 

Photos by Kenn Ranous. Taken Saturday September 24th 2016. Olympus e500 w/Zuiko 14-45mm lens. Post processing in Darktable.