High SWR on 20m stack

On Sunday 6/12/22, I was checking out the station ahead of our club’s upcoming Field Day. Running through the stacks on Tower #1, I encountered troubling readings on the 20 meter stack.

SWR on each of the three measured independently was fine; however any combination of 2 or 3 antennas sent the SWR to >6:1.

On Tuesday 6/14, I went to the cabinet at the base of the tower. I disconnected the feed lines to the three antenna from the Array Solutions Stack Match. Measuring each antenna with my Rig Expert AA-55 Zoom, I discovered that everything up the tower checked out in 100% working order.

Since I had several new Stack Match relay boxes on the shelf, I simply replaced the relay box.

Back in the shack, everything checks out!

I’ll troubleshoot the bad relay box another day!

Re-tuning 12-year old coax stub filters


Of late, I’d noticed that the SWR on the 10 and 15 meter stacks on tower 1 seemed to be getting higher and higher. Sometimes our first reaction is to head up the tower to the antenna to find out what is the trouble. This time, however, I didn’t go with that first gut reaction.

Rather, I began with a very methodical testing routine, with my AA-55 ZOOM connected to the coax in place of the transmitter at position A. I then inserted a precision dummy load at the next coax junction. Next, using the AA-55 I swept the coax on all 6 ham contest bands. I followed this pattern until I found SWR readings higher than 1.2:1.

The first thing I found was my ICE 419B bandpass filter. Even in bypass mode, it drove the SWR higher than 1.2:1. I inserted a brand new barrel connector in its place, and continued my testing.

The next problem found was on the output side of my 10-m coax filter stubs. I replace the stub assembly with another barrel connector, and continued the testing. Likewise, I found the 15-m coax filter stub assembly and the 40-m assembly to be causing SWR problems. More barrel connectors and the testing continued until I reached the distal ends of the six runs of hardline at the inputs of the various Stack Matches at the base of the tower.

The first step at remediation and repair was to test each individual coax stub in the 10, 15 and 40 meter assemblies. I found all of them to be considerable low in frequency relative to what I desired them to do. So, I retrimmed each of them to return them to the proper frequency. Then I reassembled everything, and retested. SWR was flat all the way to the base of the tower.

The second step was to replace the position A ICE 419B with a Dunestar Model 600. Following that, I again retested all the way to the tower. SWR was flat!

Things that make you go “Hmmmm”. My stubs reside in a shed, out of the sunlight and out of liquid rain. What caused them to drift over time and appear too long electrically?

Springtime + Aluminum (12-m OWA construction)

3/27/2022 – With a box of shiny tubing from DXE, and an OWA design from my friend, I tackled an antenna construction project today.

Shiny tubing for tower bling!

Since selling my Lightning Bolt 2-element 5-band cubical quad a few years ago, I have not had an antenna for 12 meters. My DXCC count is low on that band, so I figured that with the uptick in propagation, now is as good a time as any to tackle this project.

Some time ago I asked around for an OWA design to use a 24-foot boom (salvaged from an old TH6?). Once I had the design in hand, I plugged it into EZNEC 6.0, and agreed with the designer’s conclusions. Download my EZNEC file for this antenna. I made a parts list and placed an order from DXE for the tubing (surely there are others suppliers around, but I can’t find them using Google search) and another from McMaster-Carr for the hardware needed.

With some aluminum flat bar cut to length, a drill press made quick work punching holes in the boom-to-element plates (I used a DXE model as a template).

A pile of shavings!
Stack of six boom-to-element plates

The Sawzall was employed to cut the tubing to the needed lengths, followed by a thorough deburring of all tubing ends. Measured and marked the “exposed” lengths of tubing, inserted to the marks, and drilled three 1/8″ holes for pop rivets. Pulled the tubing out, deburred the drilled holes, then coated the insertable tip with a copper-impregnated anti-seize compound. Aligned the holes and riveted the tubing together. The halves of the driven element are separated by 2-inches, supported by a 0.75″ fiberglass rod inserted into both halves.

With the elements assembled, I moved outdoors to assemble the boom and install the boom-to-element plates. After that, installing the elements was a piece of cake.

This perspective doesn’t present the antenna well

Still sitting on sawhorses, the initial SWR and R,X sweeps are nearly identical to the EZNEC model.

Initial sweep still sitting on sawhorses
EZNEC 6.0 model’s SWR curve

I’ll update this post when the antenna is in service. I think it is going to be a flamethrower!

EZNEC 6.0 modeled pattern

4/15/2022 – Good Friday, and good Friday! I was off work. Woke up at 0400 and was wide-awake. Decided today was a good day to install the antenna. So, working alone with tractor and pallet forks, along with an 8-foot ladder, I was able to remove the KT-34 and install the 12-meter yagi. Initial tests are promising – worked YV4 and VP2V right away, 100 watts CW.

4/15/22 – 12-meter yagi now flying at 50 feet

2022-Feb NAQP RTTY

2/27/2022 @W5WZ – M/2, ops W5WZ, WM5H, KD5YS

We played well together and in the contest, with an apparrent 4th place finish.

During NAQP RTTY, SWR and RF PWR bargraph seemed weird. High SWR, low RF output. RF power set to 100 watts. Outboard LP-100A power meter showing SWR in normal range and power in normal range. As contest progressed, we noticed zero bars on SWR meter, and a single bar on RF meter. LP-100A was showing 100-126 watts, with normal SWR. After contest, connected a dummy load to the K3 Ant2 (easiest to do; normal antenna connected to Ant1) and the meter behaved the same. It was midnight, so didn’t do any other troubleshooting.

Within a day or two, got a support ticket open with Elecraft.

Maintainence – KT34M2

12/18/2021 — Checking out the KT34M2 in preparation of the NAQP series in January and February has revealed issues on all three bands.

Some queries to TowerTalk and the responses all pointed toward bad coax/water in coax, or loose connections between balun and front driven element and/or rear-driven element. On 1/13/22, we tested the coax and even swapped with another run. Same symptoms. A call to M2 support; they suggested perhaps water in one or more of the capacitors. We tilted the tower over to access the capacitors. Removed all 16 end caps, finding no water. We did, however, find much insect debris and dirt dauber nests. Cleaned all that out with compressed air and a long rod to push through the 3/8″ inner tube. We also verified all the mechanical connections on the driven elements and confirmed good continuity with an ohmmeter. The SWR curves are improved, but still too low.

Tower Guy Tension – You do check it regularly?

All tower owners should regularly inspect their complete tower system – guys, guy anchors, guy wires, tower base, section bolts, turnbuckles, etc – the complete tower system. Before I climb, I visually check all I can see. When I climb, I check section bolts. And about once a year, I check guy tension and adjust as needed.

10 Feb 2021NW GuyNE GuyS Guy
Top 1/4″292928
Mid 3/16″191818
Bottom 3/16″202019
Using Loos Model PT-2, I adjusted my guys to these tensions

This process led to me emailing Tim W3YQ to ask his thoughts. Here is the reply:

Well, here’s my thoughts.  Plumb is much more important than guy wire tension – within reason.  To have a tower in plumb, the whole structure is in compression.  It won’t fail.  Just like a pencil – you can’t smash it with a downward force, but you can snap it by bending it in the middle.

I know of only two ways to plumb a tower.  The first, best, and easiest is to set up two transits; 90 degrees apart.  Sight both transits to the bottom of the tower then move up to the first guy level.  Get the tower straight up to that point.  I usually use the width of a Rohn tower leg as my “good enough” standard.  If the tower’s way out of plumb, you might have to mess with the other two sets of guy wires simultaneously.  Sometimes it’s really hard to pull that first guy wire set in when the rest of the tower is fighting you.  Once the lowest set of guys is done, move up to the next set.

The tension of the three guy wires of any level will (almost) never be equal.  The only time that would occur is if you were on a perfectly flat plane and your guy anchor points are exactly on the money. Theoretical but not practical.  Someone who adjusts all three guy wires to equal tension almost certainly have a crocked tower.  Don’t worry about guy tension.  Go for plumb.  Use the tension gauge to help you get things set “close” to the suggested tensions.  Err on the side of loose instead of tight.  That 10% rule is a guideline and it’s purpose is to prevent the guy wires from galloping.  They’ll do that in the wind if they’re much too loose.  Loose guy wires, again within reason, exert less force on the structure.  Yes, when you climb, there will be a little more movement with loose guy wires, but the tower is not going to fall over.  Too tight, on the other hand, is exerting an extreme downward force on the tower.  True that if you’re perfectly in plumb it won’t collapse, but why go there.  So just use your Loos gauge as a guide.  Never go above the 10% value on any guy wire, but try to get close to that value on the one that needs the most tension.  Then adjust the other two guy wires for plumb and not tension. I usually check the tension of all three and I generally find that they’re way off from each other.  That’s OK.

The second method:  It IS possible to plumb by attaching a small rope at each guy level, one at a time.  Center it in tower, hang it down through the middle of the tower, and attach a weight at the bottom. Then stick a bucket of water for the weight to rest in.  I guess you call that a plumb bob.  The water keeps the weighted rope from swinging.  It’s kind of a PITA, but it works. 

So, this led to me purchasing a transit and acquiring another to be able to properly do “Method One” above. Once all the components arrive, I’ll post an update on the project.

CST Berger model 136

Boom + Microphone + Mount <$90

A year ago I wrote about my Christmas 2018 “self-gift”, the pair of JBL Control 2P powered monitor speakers that I integrated into my shack with a Mackie 1202-VLZ Pro. This continues to be enjoyed in my shack because I can listen to multiple sources without being tethered by a headset cord.

Similarly, I’ve been tethered by headset cord to all my microphones because they are all headset mikes. For some time, I had desired an articulating boom + microphone setup. However, I did not want to pay for brand new equipment just to try something out, and I wasn’t really sure how or where I would mount it to not be in the way when not using it.

I had read on the Elecraft reflector some interesting commentary about brands of microphones. As the K3 has a built-in transmit equalizer, it seemed the consensus leaned away from the brand that is marketed as the elite microphones for ham radio. I studied some other brands and the frequency response and cardioid patterns of several microphones.

Shure PGA 48 response charts

Soon, I found one that I was willing to buy and try. I found a new condition, open box Shure PGA48 with a 15-ft XLR cable and mic clip on eBay for $33 to my door.

What’s in the box.

At the same time on eBay, I found a used mic boom, Heil PL2 missing the cable covers and any type of mount, for $50 to my door. Tiny zip ties will hold the cable just fine.

The items arrived, and I was left with figuring out a way to mount the boom. An ‘ah-ha’ moment struck, and a simple solution was found. My radio desk has a brace under the tabletop in just the right place. I drilled a 5/8″ hole through the tabletop and into the 2×4 brace for a total depth of 2 inches. After vacuuming the shavings out, I pressed a steel sleeve bushing O.D. 5/8″, I.D. 1/2″, Length 1-1/2″ ($3 at the local hardware store) into the hole, creating a flush-mount for the boom to sit in. It works perfectly!

$3 steel sleeve bushing O.D. 5/8″, I.D. 1/2″, Length 1-1/2

Next was to listen to how I sounded with the existing TX EQ settings in the K3. I had a set of “rotating” TX macros set up to allow me to quickly step through five different TX EQ settings.

RAG-1 TE+06+06+00+06+00+04+08+12;MN110;SWT24;SWT21;SWT14;
RAG-2 TE+00+00+10+04+04+06+08+12;MN110;SWT27;SWT21;SWT14;
DX TE+00+00+00-06+00+04+08+12;MN110;SWT29;SWT21;SWT14;
VERY-DX TE-06-06+00-06+00+04+08+12;MN110;SWT33;SWT21;SWT14;
FLAT TE+00+00+00+00+00+00+00+00;MN110;SWT13;SWT21;SWT14;

After transmitting at 0.1 watts on 10m and listening via another K3 on a distant beverage antenna, I have settled on these as my initial settings for the new microphone:

SHURE TE-16-14-04+00+02+04+08+12;MN110;SWT34;SWT21;SWT14;
SHURE-DX TE-16-16-10-06+04+06+08+12;MN110;SWT32;SWT21;SWT14;

Yesterday afternoon, I enjoyed many casual QSOs on 17m and 20m using the completely “untethered” accessories. I even experimented with VOX and improved the settings to work effectively with the Shure mic.

And here it is! Boom + Microphone + Mount <$90

Summary: This is a worthwhile purchase and it will enhance my casual operating enjoyment.

Fresh Paint!

In late October 2020, I realized that the paint in the shop, shack, kitchen and bathroom was now 10 years old, and had endured rearing 4 young children. It was time for fresh paint. But instead of exclusive flat white, I got courageous and asked for suggestions from my wife Sharon KW5MOM and my adult daughter Jordan KF5GDJ.

They both suggested adding some real color to the mix, which I gladly obliged. The results were far better than I could have anticipated, and I love the colors in the entire shack area. It’s actually hard to believe what a difference it made!

Finished the project with 4 coats of clear concrete sealer on the floor.

Guests to the W5WZ ham station are immediately welcomed into a full kitchen.
The kitchen is immediately adjacent the radio room, which houses 4 operating positions. Visible in the background are positions C and D.
The kitchen is immediately adjacent the radio room, which houses 4 operating positions. Visible are positions A, B and C.
Overview of the 4 operating positions at W5WZ.
Looking from the radio room into the kitchen, the convenience of proximity is obvious!
Immediately behind positions C & D lies the test bench and the bath / laundry room door.
A new world map shower curtain adds a nice touch.
Grey wall for an accent
Christmas gift from my youngest daughter Logan KF5MTH.