Tag Archives: HF

Temporary 20m EFHW Vertical Installation

I’ve been off the air since moving back to NH in 2020. Since the landscaping has not been completed on the property, it has been impossible to install the radials for a  6-BTV vertical. Radials don’t fare well under the treads of a Bobcat.

A collection of single-band, matched, end-fed half-wave (EFHW) antennas was constructed while I was living in FL. All of these antennas underwent testing on an antenna range consisting of three 10m tall masts spaced 70 ft apart.  These antennas were matched with L-networks. The test results were reported in a separate article[1].

Seeing that July 4th weekend was approaching, I was eager to get on the air for a few days before the landscaper arrived. I decided on a 20m EFHW vertical that makes use of some of the guy ropes that were prepared for FL antenna testing. Figure 1 shows the installation of the 12.5m high telescoping fiberglass mast.  The mast is anchored with a tilt-over base mounting plate described in a separate article[2]. Guying is provided at two levels. The guying radius is 25 ft. Guy anchoring is accomplished with polycarbonate Orange Screws[3]. While these anchors work well in FL sand, they do not work quite as well in rocky New England soil. I managed to snap one of them off in the process of screwing it into the ground.

My favorite knot for adjusting the guy rope tension is the taut-line hitch. I used the taut-line hitch on the FL antenna range for three weeks, and the anchor screws came loose before any of the taut-line hitches did.

20m end-fed half-wave (EFHW) vertical

Figure 1. 20m L-Network Matched EFHW Vertical. The wire antenna and matching network is fastened to the fiberglass mast with rubber bongo ties. The mast height is 12.5m (41 ft). Base anchoring is accomplished with a hinged, tilt-over base mounting plate that was described in another article. Please click on the photo to enlarge it.

The antenna counterpoise consists of a 3 ft (~ 1m) section of outer coax shield, Figure 2. A line choke is inserted after this 3 ft section of coax to terminate the counterpoise. The remainder of coax to the shack is made up of a 40 ft long section of RG-8X.

Figure 2. Matching Network, Coaxial Shield Counterpoise and Line Choke. The matching network was designed for 14.1 MHz. Since the matching network has a wide bandwidth, the antenna wire was cut slightly longer to resonate at the very bottom of the CW band. Please click on the photo to enlarge it.

A Smith Chart is plotted in Figure 3. It shows that the antenna match over the entire band is well within the 2:1 VSWR circle.

Figure 3. Smith Chart for 20m L-Matched EFHW Antenna. A match better than 2:1 match is achieved over the entire 20m band. The antenna wire was cut longer to provide the best match at 14.025 MHz. Please click on the photo to enlarge it.

The VSWR performance is plotted in Figure 4. The matching network consists of a lowpass L-network consisting of a series inductor followed by a shunt coaxial capacitor. The antenna wire has been cut to resonate at 14.025 MHz since I enjoy operating in the bottom 50 kHz of the 20m CW band. It’s not that the VSWR performance was that bad but I just could not understand why the antenna wasn’t achieving a near-perfect 1:1 match. I turns out that the residual mismatch is in the Polyphaser lightning arrestor located in the service entrance panel.

Figure 4. 20m VSWR Plot. The L-matching network exhibits wide bandwidth and good efficiency. The antenna wire is cut to resonate at the very bottom of the CW band where I like to operate. The match is very good but not perfect. This was due to the residual VSWR in the lightning arrestor located in the service entrance panel. Please click on the photo to enlarge it.

I operated a simple station consisting of an ICOM 718 at 100W to make three consecutive CW contacts with French stations. The next three days should produce some interesting DX.

References

[1] Blustine, Martin, Highly Efficient L-Matching Networks for End-Fed Half-Wave Antennas, June 11, 2022. https://www.n1fd.org/2022/06/11/l-matching-networks/

[2] Blustine, Martin, Tilt-Over Bases for Antenna Masts That You Can Build, June 30, 2022. https://www.n1fd.org/2022/06/30/tilt-over-bases/

[3] https://www.orangescrew.com/

Tips for Working DX From a Modest Station

Lately, there has been quite a bit of nice DX out there on the HF bands.  If you are like me, you have a modest station to work from (100 watts and a wire antenna or two), but still like to chase DX. Often, you’ll hear lots of other “1 landers” working the DX station, but you can’t ever seem to break the pileup. Well, I have a few suggestions I’ve gathered over my 30 years of DX’ing and contesting that I’d like to share, which might help you get a few new ones.

One universal “truth” I have found though, above all others, is that working DX on CW is infinitely easier than working DX on SSB. If you have not yet jumped in to learn CW, I highly advise it if you want to be a successful DX’er and work the rare ones from a modest station. FT-8 / FT-4 is a bit of a different animal, and not all of what I will share is applicable to those digital modes, so I am going to focus on CW and SSB (although I work a lot of FT-8 and FT-4).

Without further ado…

#1: Listen, Listen, Listen

Did I mention you should listen? This is the first step in the process to catch that needed country. Almost all of my other recommendations stem from this… don’t be the alligator on the calling frequency… ever. A good DX’er listens far more than they transmit.

#2: Use a DX Cluster

I recommend using a DX Cluster for finding the DX.  It is much easier to find the choice DX if you have others looking for it too! If you’re not familiar with a DX Cluster, there is a good primer here. If you are but aren’t sure which to connect to, I recommend W1DX (dxc.dxusa.net:7300), unless you use Ham Radio Deluxe, in which case I suggest WA9PIE-2 (hrd.wa9pie.net:8000). They both run the DXSpider cluster software. When you use a “cluster”, you might want to set a few filters to get rid of the spots (the reports of DX activity) you don’t really want to see. Here is a couple that work on DXSpider to get you started.

From the cluster, console enter the following to only see DX spots originating from US and Canadian stations…

“reject/spot 0 by_itu 1,3” <enter>
“accept/spot 0 by_dxcc k,ve” <enter>
“sh/mydx” <enter>

Disconnect from the cluster, and then reconnect. At this point you should only see DX spots from US and VE stations

Working DX
Typical DX Cluster screen
#3: Find and Hear the DX Station’s Calling Frequency

Once you identify the DX you want to chase, go find them on the air. Sometimes, that is easier said than done. Here’s where a set of good headphones and your radio’s RX IF filters will really come in handy.

Wearing headphones is important because they filter out all that background noise.  If they are good headphones, they can also enhance the audio you are listening to and reduce fatigue.

As for your radio’s RX IF filters, this is where you may need to “RTFM”. Most modern HF radios will have some form of IF filter or DSP to shape the received audio.  On Yaesu radios, they are “Width”, “Shift”, “Contour”, and “APF”. I won’t go into detail about their use here as all radios will be a bit different.  I will say, however, that learning to use them is a critical part of effectively hearing the DX station. Ultimately, you can’t work ’em if you can’t hear ’em. Do not start calling the DX until you can reliably hear them.

#4: Find Where the DX is Listening

DX stations will listen in one of two ways… simplex (same TX and RX frequencies) or split (different TX and RX frequencies). Sometimes, the spot on the cluster will tell you where to start. However, many times the spots are not entirely right.

Simplex

If DX is working simplex, you are all set as to finding their RX frequency, but trust me… working rare DX simplex can be very difficult and painful. Always pray for split ;).

Split

If they are working split, finding the RX frequency can be a little challenging.  Remember, working split means the DX station is transmitting on one frequency and listening somewhere else.  Notice I didn’t say “on another frequency” – this is important to recognize. Many times, if the DX is listening on only one frequency, you can determine this from the DXCluster spot (i.e. “up 5”, which means that they are listening up 5 kHz from their TX frequency (such as TX: 28.507 / RX 28.512). However, often the DX is listening in a range of frequencies (i.e. “up 5-10”), which means they are listening somewhere between 5 and 10 kHz from their TX frequency (such as TX: 28.507 / RX 28.512 to 28.517). Now comes the fun part.

If the DX is listening split, it’s your job, as a skilled DX’er, to figure out their strategy and exploit it. Remember, even if the DX says “listening up 5”, they may not be listening up 5.  They may in fact be listening up 7.2 or 9.3 or 3 kHz. Your job is to figure that out. Recently, I worked a DX station on CW that would sign “UP 1”.  He was actually listening up 1.3 kHz. Had I simply called him up 1 kHz, I would not have worked him.

Patterns

To figure out their pattern and have a strategy to exploit it, you have some work to do, and likely some frustration in your future.  It’s all worth it, though, if you bag an ATNO (All Time New One). Here are some steps to follow to find the DX stations listening frequency if they are working split.

  • Use the “split” function of your radio (you do know how to use “SPLIT” on your HF rig, right?).  Set the “A” VFO to your RX frequency and the “B” VFO to a TX frequency where you think the DX is listening.
  • When the DX answers a station (i.e. “W1ABC UR 599”), flip the VFO’s so you are listening on the “B” VFO (or use your dual receive).  Now find the station that the DX answered as they give their report. This can be tough, but is essential, especially if the DX is listening across a range of frequencies. Finding the station answering the DX gives you an idea of where the DX is actually listening. Do this until you can find/hear a station that the DX answered.
  • You can now do one of two things… flip the VFOs back and start calling the DX on the frequency you found that the other station was using, or you can keep listening to find if there is a pattern (like is the DX creeping up the band, down the band, moving 500 Hz at a time, staying put, etc). Once you can figure this out, your chances of working the DX greatly improve. When you’ve got their pattern (most DX stations will have one), flip your VFOs and work ’em. Repeating the process as needed.
[Side Note – Being DX

An important side note on being a DX station that may help you be better able to work them… a good DX operator will (in my opinion):

Work split. Simplex is fine if the DX is an everyday DX station like Poland or England.  However, if they are even semi-rare, and expect pileups, they should work split. Simplex makes working rare DX very hard.  The DX’ers have to separate the DX from the calling stations, which can be nearly impossible if the stations in the pileup call over top of the DX (which they do most of the time). IMO, simplex is bad.

Manage the pileup. Managing a pileup is hard and is a learned skill. To manage a pileup, the DX operator needs a strategy. It could be nearly anything, but having a strategy allows the DX to work more stations more efficiently and with less fatigue, and makes it easier for skilled DX’ers to work them.

]

#5: Use Your Rig’s “Monitor” Feature

If you’re working SSB, use your rig’s “Monitor” feature to listen to your transmitted audio.  Do this to make sure it is not overdriven and sounds good. If you can adjust your TX audio as many new rigs can, do a little work to determine the best TX audio configuration for your voice and equipment. For many voices, there are differences in DX versus Rag Chew TX audio settings. For this, Google is your friend. (I recommend using “Monitor” for CW as well… lets you hear the quality of your transmitted tone too).

#6: Call High / Low

If you’re working CW and having a hard time working the DX on what you know is the correct frequency, try calling 100 Hz up or down from there. Sometimes that will serve to separate your signal from the others enough to work them. Due to the width of SSB signals, this rarely works on SSB, but can. Experiment.

#7: Watch Your Keying Speed

Also for CW… ideally you will match the DX’s keying speed. If they are calling at 35 WPM, call them at 35 WPM. You can go slower, but do not exceed their speed, as they may be at the top of their capability. If you send back at 45 WPM, you might never work ’em. Sometimes, however, if the pileup is full of speed demons on the key, sending a little more slowly will allow your signal to stand out. Again… experiment.

#8: Be Patient

I mean this in more than one way… it may take a while to work that ATNO, but patience on the mic or key can also pay off. While you are listening, notice if the DX is responding to stations quickly after calling “QRZ” or if there is some “dead” space in there. If there is a delay between “QRZ” and the DX responding, that may indicate that the pileup is all calling at the same time, immediately following the “QRZ”, making it impossible for the DX to discriminate calls; and the DX is waiting for a “laggard” to call them after the main pileup has finished. Be that laggard! Wait 3,4, or 5 seconds and then make your call. You might be the lone voice the DX hears!

#9: Use Proper Phonetics

Many stations like to use their own phonetics “Wally One Finger Licking Good” may sound funny, but when the conditions are marginal, there’s a huge pileup, and the DX’s first language is not English; you might as well hang up the mic. Use proper, recognized phonetics so the DX can understand your call. K0NR has a great document on proper phonetics.

#10: Use the DX Station’s First Language

I have found that using the DX station’s first language can give a 10 dB gain to your signal LOL. So, if you speak German, French, Spanish, or any other language and you find a DX station that speaks that, use it to your advantage!

To “Tail End” or Not?

While not a recommendation (hence no number), I wanted to address “tail ending”. This can be a controversial tactic, but it can also be very effective if done correctly.

Tail-ending is when you throw your callsign out at the very end of someone else’s report to the DX (for example you say “November One Xray Yankee Zulu” as soon as “K5AAA” finishes his report. It goes something like this (K5AAA says: “P5DX, UR 599 in Texas” and you immediately say “November One Xray Yankee Zulu”).

Depending on how quickly the DX responds to K5AAA and how they feel about tail-ending, you might be able to work them by doing this. Some DX do not like that practice and will not respond to “tail-enders”. Best to either see if others are successful with this or don’t do it. I personally do not like this tactic, but it can be effective (especially in contests).

Putting it Into Practice

Before you start using these tips… look back at tip #1. Your ears are your best tool to successfully work DX. Of course, there are times that you simply won’t work a DX station no matter what you do. I had that issue on the very morning I wrote this… 30 minutes of using every trick I know, and I still didn’t work them before their signal faded.

So there you have it… my top 10 list of strategies to be a successful DX’er. As always, your mileage may vary, and others may have a completely different list. Every little trick helps in my opinion. Whatever strategies you choose to employ, just get out there and have fun.

In case you are curious, I have been on both sides of the pileups, working as the DX from a number of locations with very large pileups, as well as working from my home as the DX’er. At home, I rarely run more than 100 watts and have never had more than wire antennas or a vertical… unfortunately no beams have ever graced my yard. Yet, I’ve been successful in working DXCC in a weekend during contests, and have worked DXCC on 5 bands.  I finally have a good 160M antenna up, so maybe I’ll increase my country count there too in 2023!

See you on the bands!

73 de Matt, WE1H

Hands On Tower and Beam Antenna Training for 2022 Field Day

On May 11, 2022, members of the Nashua Area Radio Society 2022 Field Day Tower and Antenna Teams met at BOB for a hands-on training exercise led by Fred AB1OC.  BOB stands for Big Orange Box, the trailer that we use to store our gear. After obtaining approval from the facility where BOB is parked, we erected a 40-foot tower with a beam antenna and other peripherals to build our team’s skills prior to Field Day in June.  We met there at 8:00 AM and began our day by removing all of the storage bins from the floor of the trailer to give us access to the tower sections, antennas, and other gear we need for the exercise.

Preparation

Plan Base Location
Plan Base Location

The next step was to identify a level spot for us to place the tilt base for the antenna that would also allow us to have room for the boom, derrick, winch, and guy lines.  Our location for the training was compact but had enough room.  In June our Field Day location has much more room, so this will not be an issue.

Field Day Tower
Prepare Base

Using the impact hammer to drive in 4-foot stakes to secure the base plate to the ground. The base is subjected to a lot of stress and strain during the lift so must be level and tightly secured to the ground.

Drive Rods with Impact Hammer
Drive Rods with Impact Hammer
Field Day Tower
Ready to Rig Falling Derrick

The team gathers around for a briefing on the next steps after assembling and installing the falling derrick pole and also setting the first section of the tower into the base.

Prepare to add tower sections
Prepare to add tower sections

Once the falling derrick is fully configured with all guys and cables attached, we raise it to lower the first tower section so we can add the remaining sections to it while on the ground.  Here as in other stages of the construction Fred is guiding us and monitoring our progress.

Field Day Tower
Bolt Tower Sections

Tower team members bolt together the tower sections securely.

Add cables and other peripherals
Add cables and other peripherals

Prior to raising the tower, all of the peripherals need to be installed.  Here is the cross beam that will hold 40-meter and 80-meter dipoles.  The coax for the beam antenna and control cable for the rotator are secured to the tower as well.

Move Assembled Antenna to Tower
Move Assembled Antenna to Tower

We orient the assembled beam antenna front down so when we raise the tower it is pointing in the proper direction. This is determined by how the tower is oriented and how the rotator is set prior to raising the tower.

Attach Antenna to Mast
Attach Antenna to Mast

We slip the U-bolts on the antenna onto the mast and tighten them.  Next, we connect the coax to the antenna with a long enough loop to allow for it to rotate more than 360 degrees.

Raise the Tower

View the Hyperlapse above

Watching Rotator Test
Watching Rotator Test

The crew watches as we test the rotator and confirm that there is enough loop to rotate without any interference or binding. The test was successful and afterward, Fred AB1OC made a few DX calls to Europe QRP with an IC-705 radio.  The beam worked great!

Disassembly and Storage

Prepare to Remove Antenna from Tower Mast
Prepare to Remove Antenna from Tower Mast

Around 2:30, after only 15 minutes of operating, we needed to reverse the process and disassemble the tower and antenna. Our target time for departing the facility was around 4:00 PM.

Remove Antenna from Tower
Remove Antenna from Tower

The Beam team removes the antenna and moves it for disassembly until Field Day. At the same time, the Tower team will break down the tower and peripherals.

Ready to Disassemble Antenna
Ready to Disassemble Antenna

We place a tarp under the antenna in case any small parts fall off.  It is easier to find them from the tarp than from the tall grass.  Working on it on the sawhorses makes it much easier to assemble or disassemble.

Breaking Down Tower Sections
Breaking Down Tower Sections

The Tower Team breaks down the tower sections while carefully keeping track of everything so we can be sure we have what we need for Field Day at the end of June.

Gear Stowed and Ready to Leave After Successful Day
Gear Stowed and Ready to Leave After Successful Day

We are ready to leave after a successful day. Thanks to Fred AB1OC who guided us through the different activities. He helped us all to gain more information on how to perform this task safely and efficiently.

Field Day can be a complex project

Field Day provides clubs with a number of opportunities.  The obvious are to have a chance for members to gather and operate together.  Even though it is not a contest, per se, we do keep score. The event also provides a chance for members to participate in a complex group project.  Some of us had experience with projects of similar complexity in our careers but others never did.  Working together collaboratively on a project like this is a good basis for friendship and memories of the shared experience are long-lasting.

Building Skillsets in the Club

One of our goals as a club is to build a skill set within the club that persists as members move in and out of active participation in these activities.  We have members this year who have years of past experience doing this and others for whom this is their first exposure to it.  Members who were prime contributors a few years ago may no longer participate. After this Field Day, we will have a new core of experienced members who can handle these tasks and share their own experiences to mentor the new members who will follow them.  We strive to build a culture that continues to promote the continued building of the required skills in the club to share with future members.

Jon AC1EV

Radio Amateurs Developing Skills Worldwide