Need help tuning a Workman Duel Band fiberglass Antenna

[KQ4BX]

I have a Workman fiberglass antenna that can comer apart to be tuned. I had decent 2m SWR, and lower .70 before I started. I tested the bands and found that the antenna worked better at the bottom of the bands, so I assumed it was too long and took an inch from the top. That was probably a bad idea, but as it is now, I am sure I am not handing this tuning properly.
I have a flat SWR from 339 - 442, at 442 is where is stats to climb, and it is still pretty good up to almost 443, but way off by the time I get to 444. I now have messed up 2m, so that is why I know I did something wrong
The inside of the antenna has what appears to be a single wire in the lower section that I can't get at easily, the part I can get to starts with one long coil at the lower section, and a shorter coil towards the top, with a straight piece coming out of the top where I cut at least two inches off. I then compressed the long coil a little, and ended up with what I have now. I would like to push up the band in .70, and regain my 2m operation , which is far off from where it should be.

Does anyone have enough experience with antenna design to offer some advice on where to take it from here?

 

[dksac2]

You may wish to solder the top 2" back on. There are hex screws that hold the two parts of the antenna on the inside , it is best to adjust section lengths at those points until you get to where you want to be, than to just cut the top part of the wire in the antenna.
Be sure to seal the parts of the outer fiberglass pole at the joints. Water is known to get into the joints and ruin the antenna. Also, if the antenna is used, check the disc capacitors as water ruins them when it gets inside of the antenna. If you notice the caps look melted, they got wet, just replace them with like values.
I used to vacation in Jensen Beach in the mid 1960's. It sure was a beautiful small town then. I've looked on line, it's not the nice cozy little town it used to be. I'm sure it's still a great place, but nothing like I remember for sure.
When the sharks were spotted in the ocean, the lifeguard would get everyone out of the water and shoot the sharks with an old military rifle. Bet they don't do that today. Used to be a lifeguard shack with a covered picnic area and just a hundred yards away, a small greasy spoon. Other than that, just miles of vacant beach. The towns sidewalks were made of wood. Miss those days.
73's John

 

[KQ4BX]

I saw the hex screw holding at the bottom, but it was too far down into the tube to feel like I could put it back, even though I was sure I could take it apart. I will take another look and see if I can get it apart without destroying it.
As for Jensen Beach, I have lived in Florida for 20 years, and even in those 20 years the beach area has changed a lot. We have a lot of mansions along the beach, the kind that get destroyed in hurricanes, just so out tax dollars can help them rebuild. Jensen is still smallish. I grew up on the jersey shore, Long Branch to be exact, and I live one block from the beach. Long Branch is a far cry from what it was when I was young, that would be early 70's. Nothing is the same there, just as you might feel that nothing is the same here. I love living in Jensen Beach, but in the last 10 or so years, I have developed allergies to most of what is green. I don't have those allergies when I go back to where I was born. I can retire in 5 years, and by then I will have a good idea of where I want to spend the rest of my life.

I bought a Diamond duel band antenna to take the place of the Workman, but the Diamond has 1.4:1 at those high UHF frequencies, so a duel band antenna might be nice, but it can't beat two separate antennas that are tuned for exactly where you want to be. The Workman is a lot bigger than the Diamond. That surprised me when I considered how much it cost.

Thanks for replying with so many details. I'll give thge antenna a second look this weekend.

Tnx, Joe KQ4BX

 

[dksac2]

I hope it works out for you. I had to rebuild a Opek vertical which is about the same as a Workman due to water getting through the joints.
It worked well after the rebuild. As to 1:1.3 SWR, that really is not all that bad. You'll loose very little power. Just be sure to use something such as LMR-400 at the VHF /UHF frequency's and try to keep the run as short as you can. You'll loose far more in power with lesser coax than the SWR will lose.
I ended up moving to Idaho, cold, no beaches, but wonderful rural areas and great people. I think we are one of the few "Free" states left.

73'S John

 

[KQ4BX]

Well, I lost the piece I cut from the top of the antenna, but I also discovered that the entire internal radiating elements can be slid out from the bottom by gripping the S)-239 with a pair of pliers and unscrewing it.

Can someone who has access to one of these be so kind as to unscrew it from the bottom, slide it out and measure the top section, from the tip to where it comes apart from the bottom section?

I first have to put that part back, because it relates more to 2 M resonance than it does to .70 CM resonance. I should have found a way to take the bottom section apart before I started cutting at the top.

Live and learn. Can anyone assist in this measurement, or know anywhere where it can be found?

Tnx, Joe

 

[teufler]

Drop workman a line, Workman Electronic Products
11955 County Road 10-2
Delta, Ohio 43515-9748
800.537.7107
Fax: 419.923.7145
Copyright 2004

 

[KQ4BX]

I have had a recent talk with them when I lost the bottom section of the antenna. They did eventually find a used part that they sent me for the cost of shipping, but that experience told me that they are not so technical when it comes to their products. They will do what they can teo help, but to ask them to take an antenna apart and measure it would be something I would bet against.

Hams buy these anteannas often, so I am only asklng if soimeone gets the chance, please measure it before putting it up.

Tnx, Joe