Monthly Archives: March 2020

Social Distancing for the Amateur Radio Operator…

Leave a comment Posted by on March 30, 2020

Thanks to Keith G6NHU!

ham radio, LIFE

2020 CQ WPX SSB Contest

Leave a comment Posted by on March 30, 2020

I have been somewhat preoccupied here with the whole Corona Virus situation that I completely overlooked that the 2020 CQ WPX SSB contest was taking place this weekend. I started on Saturday running as a single operator QRP station. Had I prepared, I would have likely setup the 20m Inverted V but instead I ran on the S9V31 vertical. My results ended up quite comparable to last year’s result with 52 QSO’s covering 17 countries and 47 distinct prefixes:

15m worked out to be my best band with most of the longer distance QSO’s particularly south of my QTH. 20m was a challenge as there were many stations competing with considerable QRB & QRM. I managed a few contacts on 10m & 40m. 40m was mainly opportunistic as I did not stay up late to work the contest.

I believe next time I try this I will set up an antenna for 15m.

Antennas, Contests, ham radio , ,

Raspberry Pi Ham Radio Setup

Leave a comment Posted by on March 26, 2020

I have struggled a bit with configuring my Raspberry Pi for use in the field. The issues I am having have received around networking as I need to configure the Raspberry Pi “headless” over WiFi. It is easy enough to get the RPi setup for that and then install the ham radio apps one by one. The problem comes from trying to setup a WiFi access point when I am away from a WiFi connection. To make a long story short I finally figured this out with help from some setup scripts provided by KM4ACK.

These scripts make the setup very easy. Building FLDigi from source is time consuming but it works on its own. The whole script installs RTC & GPS if you have the hardware for it as well as the most commonly used Linux based ham radio apps. Unlike other methods, the WiFi access point works pretty well. If you are in range of your home network it will hook up to it normally. If it doesn’t see your home network it goes into access point mode at IP address 10.10.10.10. Here is the pi with RTC, GPS & sound dongle being controlled with an Android tablet with Bluetooth keyboard:

Now that the Raspberry Pi is configured I’ll start working on setting up a 12V to 5V buck converter installed.

ham radio, HF Portable , , , ,

Nothing is Ever Easy…

Leave a comment Posted by on March 24, 2020

The Ed Fong antenna is up about 20 ft on the military mast and tripod. Voice FM is working fine business. I tried Packet Winlink but could not get it to work. After confirming the local digipeater was indeed active, I rechecked my configuration and found that the sound card port was not correct. It sync’d up fine to KRAV-10 via the BRO digipeater.

I mounted a cross beam on the mast to support the mini-whip antenna which I connected to the SDRplay. The fun started when I loaded the drivers. The software would hang up and I’d get the blue screen of death. This is a royal pain with the HP workstation as it rebuilds the RAID drives every time a crash occurs. The whole machine gets real slow and it can take an hour to rebuild the drive. Just booting the machine up from a crash takes 20 minutes.

The problem turned out to be a setting in Windows 7 that powers down the USB bus as part of the power management settings. This may have resolved a long staring issue I was having with USB devices on this machine. The SDRplay software works just fine now along with the mini-whip antenna.

Getting all this working comes just in time as the county has issued an order that everyone is to “shelter in place” for 14 days due to the Coronavirus. At least my comma are ready.

Antennas, ARES, ham radio, LIFE, VHF , , , , , , , , ,

Back on the air on VHF/UHF

Leave a comment Posted by on March 22, 2020

I have been off the air on VHF/UHF for about 9 months now with my only access either in the car or on an HT. I setup the military mast today with the Ed Fong antenna along with a mini-whip for HF use. This will be a temporary setup to cover local communications during the current health emergency.  It gives me a chance to test the setup before I make it permanent by attaching to the house.

IMG_0599

Antennas, ham radio, VHF , , , , , ,

Since No One Else is Saying It…

Leave a comment Posted by on March 16, 2020

Keep-calm-and-carry-on-scan

ham radio, LIFE

A 2-Element Wire Beam for 20m Using a Single Mast

Leave a comment Posted by on March 13, 2020

I came across an idea for a 2-element wire beam that can be supported by a single mast. There was not much detail on construction but some EZNEC modeling shows that it would work. Here is what I have thus far:

2020-03-13

A single support point hold both the feed point and the center of the reflector element. Gain over average ground is about 9 dbi with decent front to back rejection. I will need to build a 1:4 balun for the feedpoint and it looks to be a bit narrow banded but should be about the easiest full size beam that I can come up with.

I’ll be doing some additional optimization on EZNEC to bring the tuning in and will be building the match for this. This could be the field antenna for 20m that I have been looking for. 9 dbi of gain brings a 5W single up to 40W ERP!

Antennas, ham radio, HF Portable , , , , , , ,

Mount Components Re-designed —- Again!

Leave a comment Posted by on March 10, 2020

Designing a component is truly an iterative process that is greatly facilitated by 3D printing. Case in point are the fishing pole adapters I am using on the 20m vertical beam. These started out with threads that would screw into the bottom of the pole. These did not have enough screw engagement and would pull out without much force. I then came up with the expanding mandrel design. This fixed the grip problem and the screw would reinforce the shaft from lateral forces. This worked particularly well with the fiberglass fishing poles as there inner diameter is larger and allows me to use a 1/4-20 screw. Then I sourced the longer carbon fiber fishing poles that have a smaller ID and had to redesign the mount to hold a #10 screw. After a couple of days in light winds the plastic snapped off at the base leaving the screw as the only thing holding everything together. Lateral forces were strong enough to bend the screw at about a 45° angle before I took it down. I have now redesigned the part to provide additional lateral strength:

The original design was printed along the cylindrical axis. Picture each layer like stacking coins. The weakest part of the print is in between layers so naturally this is where the part failed. I redesigned the part to print lengthwise. To do this I added a flat on one side and removed the integrated guy ring. The guy ring I now print separately. The part printed very nicely and feels much stronger in the lateral direction. I will be testing these parts soon but I think I have a winner.

Nice lessons learned about how to orient the part design for strength. I have a few more tricks to try if I need even more strength but more on that later.

Antennas, ham radio, HF Portable , , , , ,

Powered up the Xiegu G90

Leave a comment Posted by on March 10, 2020

I wired up some Anderson PowerPoles to the G90 wire harness and connected up the 20m vertical beam for a quick power up. I hooked it up to a 12V 5A power brick and powered up the rig. Everything came up nicely and I tried a few functions including the built in tuner. Nice first impression of receive audio. Interface needs a bit of practice and I’ll likely need to upgrade the firmware to the latest and greatest.

ham radio, HF Portable ,

QRP Bug Bites!

Leave a comment Posted by on March 9, 2020

I am reconsidering operations using QRP after having had some good and more importantly FUN results on DX contests. The challenge really comes down to optimizing your signal for the kind of operating you will be doing. The needs of field day vs a DX contest on QRP are different. There really are two things to consider:

  1. Minimize system loss.
  2. Maximize antenna gain.

I’ll be focusing some effort on these issues and will likely expand my operations on QRP.

 

 

Antennas, ham radio, HF Portable , , ,

← Older posts