Antennas, experiments, engineering and other articles of interest to radio folks.
Many hams add power hungry radios to their vehicle power systems. A preferred way to obtain the power is directly from the battery terminals.
I have been adding various gadgets to my Ford Taurus to bring battery power into my passenger area so I can get rid of my cigarette lighter plug for my 2m/440 radio.
Adding a wire to my original battery posts was a problem so I used replacement posts from the car audio market. This turned out to be a mistake.
Running a fan on low voltage can keep your power supply much cooler without making a lot of noise.
The new antenna for 2010 at this QTH will be the popular G3TXQ Broadbeam Hex Beam. What follows is a look at the DX Engineering Hex Hub.
YouTube helps to document helpful Haiti EmComm.
Can the 10-20 meter five band HF G3TXQ broadband hex beam be used on 6 meters as is?
The Haiti disaster will highlight the ability of amateur radio to provide useful help.
Continuing our discussion of Single Operator Two Radio (SO2R) station design brings us to the topic of antenna routing.
Previously we discussed SO2R gear arrangements which have two antennas connected to two radios, one antenna for each radio.
If all you have are two antennas for your two radios then there really is no point in putting in a matrix to allow either antenna to route to either radio.
However, let’s assume you do have a pressing need to multiplex the antennas and use this as an evolutionary step in our series of posts.
Continuing our discussion about SO2R technical discussion brings a focus to the concerns of cross band interference between your two radios.
Having one transmitter spewing energy at full power while trying to listen on the other radio’s receiver is daunting. Unless you have an Elecraft K3, your radio’s ability to perform adequate band pass filtering is probably not sufficient for the 2nd and 3rd harmonics from the transmitter resulting in severe de-sense of the receiver signal chain.
Orienting the antennas to minimize their interaction will help. If you are lucky you may well achieve good isolation between at least some of the cross band combinations.
To help radios avoid this interaction, a few manufacturers have products which provide excellent band pass filtering.
In my many years as a ham, I somehow missed the whole topic of the Single Operator Two Radio (SO2R) technique for amateur radio contesting. I pulled up a few YouTube videos showcasing the great operators using this technique and convinced myself SO2R is interesting enough to research.
The ability to add a bit more excitement to those late contest constant CQs with an additional radio looking for other contacts, especially new multipliers, is inviting.
There are many resources on the Internet about why to do SO2R. I invite the reader to explore these resources. We will review a couple key concepts on why to do SO2R and then dig in deep to some technical approaches.
Which full-wave loop to try first: 40 meter, 80 meter, 160 meter, more?
One thing I notice a lot during contests with my trusty Icom IC-746 (pre pro) is the splatter from power house stations nearby in frequency. I realize I can’t keep their splatter out if it falls within the passband of my receiver. However, I can at least try a more narrow filter to mitigate out of band energy.
The IC-746 comes with a 2.4 kHz wide filters for the first 9 MHz IF and for the second 455 kHz IF along with some wide options for AM and FM use.
I purchased this radio from a CW operator so it was no surprise what I found in the two 9 MHz optional slots: 350 and 250 kHz filters. They work real well for CW and, I suppose, the wider of the two would be good for RTTY work which I am just starting to use.
However, I do lots of SSB work and often get the AGC following the nearby signals rather than the one I want. So I really wanted to try out the 1.9 kHz Icom FL-223. It did not take long to find one on E-Bay from… Taiwan no less. In about a week I had my package.
Photo album showcasing the creation of a home made ladder transmission line.
Keep it simple for the Jamboree on the Air – Use a ladder line fed dipole.
I was chatting with a club member this weekend. He told me about a digital slow scan tv modulation mode designed for use in the HF bands on a typical SSB bandwidth.
I know about analog slow scan television and have heard about many binary transfer methods for HF. This was the first time I heard something coined “Digital Slow Scan TV.” The program is called Easypal and can be found easily via a web search.
There appears to be a dedicated team behind this program which suggests a healthy development effort.
Indeed, after downloading the program and installing it on a Windows XP system, I was using it in no time. My friend was on the local repeater at the time and guided me through appropriate default options to use.
A Lighthouse QSO Party organized in the traditional QSO Party theme sounds fun, but would anyone care?
Here are some details regarding the next, and probably last, phase of my 43 Foot DX Engineering vertical installation.
This post is very late. The actual date of the events within it are just before March 2009 in preparation for the Virginia QSO Party.
In the many posts within this site, it is no secret my examination of various vertical antenna solutions with comparison between BigIR and the 43 Foot products a big part of this. Check out all the 43 Foot posts on HHD here…
Earlier this year I purchased the Navigator from US Interface. It has done a very nice job mopping up various connections between my computer and the Icom IC-746 transceiver.
I used this fine interface with great success, however, last week it blew its fuse.
“Put a Hex on you…” Three antenna suppliers are making the Hex Beam antenna an easier choice for your next 20-10 meter beam.
Hiking, ham radio, hills and a portable collinear J-Pole combine to make the Golden Packet Test a memorable event.
You all might be wondering if Blogger John, that’s me, has finally tip toed off the deep end with this review of the new LED lamps as a replacement for incandescent lamps.
Yes, yes I know it is a bit of a reach. However, this is somewhat of a technology web site and ham radio does have tech savvy folks.
The topic of ham shack lighting is certainly important for good operating ergonomics. Can the amateur radio operator benefit from the latest advances in home lighting products?
Who is in charge of the Ohio QSO Party?
We examine if 5/8 Wave J-Poles are better than 1/2 Wave J-Poles.
OK so I decided to buy the base K2 kit and build it along with my son.
Choosing Elecraft is a no brainer, but any of the other kit manufacturers would be fine also. The point it to give a young man an opportunity to see something start from a box of parts and become a higher level assembly.
We are also considering the Elecraft KX1 as a good starter kit. We have already built several of the other smaller Elecraft kits.
Here is a summary of our current situation…
The summary of the very helpful answers are…