Jackite Pole Repairs

As you can tell from other posts, I’m a big fan of Jackite fiberglass poles.  My 31-foot pole sees heavy use as the main component of my Pop-up Vertical antenna. I also use it a variety of other portable situations, including my Bike Rack Vertical antenna.

Recently, I was in a wooded area and had the pole strapped to a signpost. While packing up to leave, the tip section got stuck.  It refused to slide back into the next larger section.  I noticed that the split ring I have attached to the top eyelet (see my Jackite Hacks post) had some damage. I’m guessing it got hung up in a tree branch when I was collapsing the pole.  My downward pulling most likely caused the top two sections to become jammed.

Damaged split ring. (Click for full-size image.)
Damaged split ring. A possible clue as to how two sections of my Jackite pole became hopelessly jammed.

I have had these two sections become stuck once or twice before.  I guess I’m sometimes a bit too aggressive when I extend the sections.  Usually, a little WD-40 does the trick.  Not this time.

I worked on it when I got home and wound up cracking the tip section.  The two sections were still stuck together.  After few minutes on the Jackite website, a new tip section and the next larger section were on order.  I received a shipping notice the next day. The cost was reasonable.  It was definitely less expensive than replacing the entire pole.  A couple of days later, the parts arrived and the pole is ready to head out into the field again.

Thanks to the good folks at Jackite, I’m back in business.  I’ll try to be more careful next time.

72, Craig WB3GCK

Disclaimer:  I have no interests, financial or otherwise, in Jackite.  I’m just a happy customer.

QRP by the River

I haven’t been able to get out to do any portable operating in while.  I had a few hours this morning before we headed out of town to spend the weekend with family, so I thought I do a quick trip to nearby Upper Schuylkill Valley Park.  The forecast was calling for rain, so my original plan was to operate from my truck with my antenna mounted on my bicycle rack.

When I arrived at the park, it was a mild 55 degrees (

A conveniently-placed bulletin board served as my antenna support.
A conveniently-placed bulletin board served as my antenna support.

) with no wind and no rain.  I figured there won’t be many more days like this for a while, so I decided to head further into the park and operate from a picnic table next to the Schuylkill River.  My antenna was a 30-foot vertical wire fed through a 9:1 unun.  I used some nylon cable ties to secure my 31-foot Jackite pole to a sign post.  My rig was my trusty YouKits HB-1B.

I started out on 20 meters.  The band was jam packed with stations working the CQ DX Contest.  I’m not a big fan of the quick contest-type exchanges so, after working PJ2T, I moved down to the more peaceful 30 meter band.

WB3GCK operating by the Schuylkill River
WB3GCK operating by the Schuylkill River

W9ZN was booming into Pennsylvania so I gave him a call.  I’ve worked Bill several times before from a variety of portable locations and it was nice to work him again.  We had a nice chat until the band started fading.

Next, I moved down to 40 meters and called CQ.  W2ZRA gave me a call from Eastern Long Island.  We had a nice rag chew.  Kevin was running 50 watts and I gave him a 589 signal report.  During the QSO, he reduced his power to 5 watts and was still about 569.

After that, I needed to pack up and head home.  My timing was impeccable; it started raining a few minutes after I got home.

It was a very brief but enjoyable morning to be operating outdoors by the river.

72, Craig WB3GCK

 

 

AlexLoop Mounting

In my 40+ years in Amateur Radio, the AlexLoop Walkham was the first commercially-made HF antenna I ever bought.  I wanted something for those spur-of-the-moment QRP outings when I want to get on the air quickly and not have to deal with putting wires into trees.  The AlexLoop fit the bill nicely.  There’s probably nothing novel or new here but here’s how I mount the AlexLoop for operation.

Tripod Mounting.  While I was waiting for the AlexLoop to arrive from Brazil, I ordered a Vivitar VPT-1250 tripod from a vendor on eBay for less than $20.  The VPT-1250 is super lightweight and stores nicely in the AlexLoop’s carrying bag.  It’s a decent tripod for casual use but for something like a SOTA activation under windy conditions, you’d be better off with something more robust.

vivitar_tripod_2
Vivitar VPT-1250 Tripod with PVC pipe installed.

To use the VPT-1250, I removed the pan/tilt head.  I cut a 4-inch piece of 1/2-inch PVC pipe, which I slide over the center post of the tripod.  I added a bit of electrical tape to both the tripod post and the PVC pipe to give a slight friction fit.  The base of the AlexLoop slides onto the PVC pipe.

Picnic Table Mounting.  This is an idea I got from AK4LP’s QRZ page. For mounting to a table, I take the same piece of PVC pipe and insert it into a 1/2-inch PVC elbow fitting.  I sanded the end of the PVC pipe so it was easier to remove from the elbow fitting.

table_mount_1
Table mount attached

I just use a 2-inch C-clamp to secure the pipe and elbow fitting to the side of the table.  Again, the base of the AlexLoop just slides over the pipe.  I store the PVC parts and the C-clamp in the tripod’s nylon carrying bag.  When a picnic table is available, this mount goes to together faster than setting up the tripod.

table_mount_2
AlexLoop base mounted to table

If anyone knows the ham who came up with the picnic table mounting idea, let me know in the comments and I’ll make sure he gets credit for it.

UPDATE (11/16/2015):  I remember now where I got the idea for the picnic table mount and have updated the post accordingly.  Many thanks to Bob AK4LP for coming up with this simple and novel idea!  Be sure to check out his page on QRZ.com for pictures of his picnic table portable setup.  I had the pleasure of working him at that Smith Mountain Lake location back in 2013 while I was camping in Maryland.

73, Craig WB3GCK

Line Isolator

One of my favorite portable antennas is a 30-ft wire fed through a 9:1 unun.  This type of antenna generally the uses coax feeder as a counterpoise, since the 9:1 unun configuration provides no line isolation.  Most of the time, this has worked well for me with no issues with stray RF getting back into the equipment.

On a couple of occasions, my Elecraft T1 auto tuner began to act up, refusing to load up on one or more bands. (Running through the T1’s diagnostic mode always seems to restore operation to normal.)  I’ve also had one of my keyers behave erratically once or twice.  Since this has only happened when using the 9:1 unun, my suspicion is that common-mode RF currents on the coax shield are the culprit.

My proposed solution for this is to use a line isolator between the tuner and the coax feeder.  (Note:  Using a line isolator at the antenna end of the coax would defeat the purpose in using the coax as a counterpoise.)  A quick survey of my junk box stash of parts showed I had everything I need to build a line isolator from scratch.

Parts List

  • RG-174/U coax (approximately 24 inches)
  • FT-140-43 ferrite core
  • (2) BNC-F chassis mount connectors
  • Hammond Manufacturing 1591MSBK Enclosure (2.2 x 3.3 x 0.8 inches)

Construction

This is a very simple project.  You can build one in well under an hour.

  • The RG-174 coax is wound on the FT-140-43 core for a total of 10 turns.  Take note of how the 5th turn goes across the core.  This makes installation in the case a little easier.  I used a couple of small nylon tie-wraps to hold the windings in place.
  • Drill the holes for each of the BNC connectors and wired up the choke, as shown.  I used a 5/64-inch drill bit and had to use a reamer to get the holes to the right size for the BNC connectors I used.
  • Solder the coax to the BNC connectors.
  • To mechanically secure the core, I used a piece of two-sided foam mounting tape to mount the choke to the bottom of the case.  As an additional precaution, I put a piece of packing foam on top of the choke before attaching the lid.  This foam provides a slight downward pressure on the choke to prevent it from shaking loose in the case during handling.
line_isolator_core
Core winding
isolator_core_installed
Core installed in case

Testing

I don’t have access to the equipment necessary to do any type of exhaustive testing of the line isolator.  In lieu of that, I hooked it up to a 50-ohm dummy load and checked the SWR.  It was basically flat from 160M through 6M.  While that tells me nothing about how effective it is in reducing common-mode currents, I at least know I didn’t make any serious screw-ups in building it.

2015-11-08 13.45.50
Completed line isolator

In Operation

Well, this part will have to wait until I have a chance to get out for some portable operating.  I want to make sure that the line isolator doesn’t affect the T1’s ability to tune my antenna.  Since the initial problems were very intermittent, only time will tell if I solved those problems or not.  I’ll be sure to update this post with any new insights I gain.

Update 5/16/2017:

Since this article seems to get a lot of traffic, I figured it was time for a long-overdue update.  Not long after this post was published, I tested this 1:1 unun in line with the coax to my 30-foot wire and 9:1 unun.  As I suspected it might, it affected the tuning of the antenna.  One or two bands wouldn’t load up properly.  This made sense to me, since this antenna configuration relies on the shield of the coax for the counterpoise.  So, there’s some RF on the coax shield by design.  This device obviously is blocking some RF, as it should.  I haven’t pursued it further and I still have done any measurements to determine its effectiveness.  With a change of connectors on the output side, it could definitely be useful as a 1:1 balun, I suppose.

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Tilt Stand for the YouKits HB-1B

This is another one of those projects that took longer to write up than to build.

The top facing controls on “trail-friendly” radios like the YouKits HB-1B and others are very convenient when you’re sitting on the ground out in the middle of nowhere. When operating “picnic-table-portable,” however, the display can sometimes be a little hard to read. For those situations, I came up with a little tilt stand using some stuff I had on hand.

tiltstand-1
Magnet applied to the corner brace.

The tilt stand I came up with has a grand total of two parts. First is a steel inside corner brace. You can find these at any hardware store. The one I used is 3/4-inch on each side and 1.5 inches long. You can use whatever size gives you the amount of tilt you’re looking for. The other item is a small but powerful magnet. The one I used is about the size of a nickel. I secured it to the corner brace using some Goop adhesive. To use the tilt stand, just use the magnet to put it on the bottom of the HB-1B, as shown in the pictures.

tiltstand-2
Tilt stand attached to the radio

This tilt stand works best when you have rubber feet on the bottom of the radio, as I have on mine. In fact, I added those the first time I used the radio, to keep it from sliding around on my desk.

tiltstand-3
Tilt stand in use

This little gizmo will a permanent part of my HB-1B portable station for those “picnic-table-portable” operations.

73, Craig WB3GCK

Clipboard Keyer

I purchased a set of Palm Mini paddles for portable operating a while back. I love the magnet base, which attaches nicely to the side of my little YouKits HB-1B transceiver. However, in some situations — like sitting on the ground or operating from inside my truck — that isn’t always the most convenient arrangement for me. Here’s a little hack I came up with to solve that problem.

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Figure 1. Washers attached to clipboard
clipboard-2
Figure 2. Paddles attached to clipboard

I purchased an inexpensive 6-inch by 9-inch, acrylic clipboard at my local office supply store. I used some GOOP adhesive to attach two steel washers to the clipboard, as shown in Figure 1. I made sure that the washers lined up with the magnets on the base of the paddles. Figure 2 shows the paddles attached to the clipboard. Figure 3 shows the clipboard in use during a recent outing. For transport, the little clipboard fits in the small plastic container I use for the HB-1B and accessories.

clipboard-3
Figure 3. Clipboard & paddles in use

For less than $2.00, this little accessory makes portable operating a bit more convenient.

73, Craig WB3GCK

Jackite Pole Hacks

I’m a big fan of the Jackite fiberglass poles for portable antenna supports. I have two of them have have seen a lot of use over the years. Here are a couple of quick and simple hacks that improve (in my opinion) on an already great product.

Keeping the Cap From Falling Off

While the overall quality of Jackite’s products is excellent, there is one thing that I find annoying — the caps have a tendency to fall off when transporting the pole. To overcome this, I attached a velcro strap to the cap (Figure 1). The Velcro is something I had on hand in my junkbox. It’s about 8 inches long by 1 inch wide. I used a #4 machine screw with some flat washers, a lock washer and a nut (Figure 2). I used an awl and a small phillips screw driver to make the hole in the cap. I then attached two Velcro strips (the fuzzy part) on either side of the pole (Figure 3). When transporting the pole, just secure the Velcro straps (Figure 4) and you’re good-to-go.

Figure 1
Figure 1
Figure 2
Figure 2
Figure 3
Figure 3
Figure 4
Figure 4

Easy Extension

This quick mod might seem kinda pointless to some users. In fact, I hesitated about writing it up. Anyway, you be the judge:

Figure 5
Figure 5

In cases when I need to bungee or strap the pole to a fixed support, I would first need to extend the top-most section first. This is because the top section sits down inside the other sections when collapsed. What I did was attach a key ring (aka split ring) to the eyelet on the top section (Figure 5). The ring I used is approximately 7/8-inch in diameter. So, I can strap the collapsed pole to a support, remove the cap, reach in and use the ring to pull the top section out (Figure 6).

Figure 6
Figure 6

Again, you might not see the value in this one, but I find it helpful.

73, Craig WB3GCK