Monday, March 27, 2017

Winch Update

Well I tested the winch over the weekend and things were not so good. I could raise fairly well but the pole was always lifting and swaying at a horizontal angle, plus the bottom attachment of the pole was getting caught.

I tried various ways to fix it, but unfortunately it proved too difficult. In the end I gave up, I was just about to concrete in when I thought this is pointless it's just not working properly and in future years, I would be raising up and down sometimes on a regular basis for testing antennas. If it wasn't working correctly now, what would it be like in a few months time?

I really needed something more solid, so in the end after much thought I gave it up. It was annoying as I rarely give in, I like to work things out and repair, but something as important as this has to be right. When I retire in the next few years, this will be my main hobby and I will be experimenting with different homebrew antennas, so I want to have a mast that raises and lowers easily which is permanent and more importantly will last.

So reluctantly, I have now ordered a 35 foot professional built mast with two winches one for lifting the mast upright the other to raise. I've already dug out the hole for its sleeve which is 500mm deep and 1m square. The sleeve is coming sometime next week and I can go ahead and get it concreted in ready for the full mast which will be arriving sometime in late April.

Something's you win and something's you lose!

Friday, March 24, 2017

Completion of Tilt Over Mast & An Antenna at Last

Continuing with the building of the homebrew wind up/tilt over mast, I have at last managed to finish the build, but due to the past week of heavy winds not yet tested.

I actually completed on Monday, but on looking at the pulley which was first placed directly below the winch, I felt the angle was too direct and would probably cause some kind of an issue, I think the raised pole would hit the pulley. Suffice to say I bought two steel rectangular plates, cut them to size and fitted so that the pulley came out and away from the scaffold poles, so as to create more of gap between the main pole and the scaffold poles. My geometry has never been much good, but you just know when you get that feeling that something could work better if you redesigned it, and besides it looks better!

I've buried the two upright poles 3 feet in the ground and I'll concrete and ballast when and I'm completely happy it's all working as it should be.

I think it's a reasonable effort and should be OK for some light antenna work, anyway it will save me from further back ache! But I'll do some more testing this weekend.

I took the Moxon down after seeing the rotator swing in the high winds and presumed it was too weak for the 17m Moxon. But in actual fact when fitting the winch I notice some of the nuts attaching the rotator to the aluminium scaffold pole were loose, realising this was the probable cause of the free rotation, doh!  So instead, I have now fitted the 6 element 2m Yagi, I'm going to leave it  for the moment and try out 2 metres this weekend.

After much thinking, reviewing and mulling over, I have finally chosen an new antenna and it's a mix between a beam and an Omni directional, its called a Dual Beam Pro antenna by Pro antennas   It's very light and reasonably unobtrusive so wont annoy the villagers and it has bidirectional characteristics requiring only 180 degrees rotation to cover the globe.

The dual beam pro, interesting shape?

I must admit at first I was all for a mini beam or a Yagi, but after reading the write ups and seeing it has a good score in E-ham reviews. I bit the bullet and purchased it and am now eagerly awaiting it's arrival. I will do a separate review of the antenna at a later date. 

Tuesday, March 21, 2017

Hustler 18 and 24Mhz Upgrade

On a past post I told you about my Hustler 6BTV upgrade which I  added the 24Mhz and 18Mhz elements by tapping at the base of the antenna. This is a simple process that literally takes a morning to do and adds two more bands to the antenna.

Just by adding the two elements horizontally each side of the base of the antenna for about a foot and then raising vertically and hanging at the top you have the two extra bands.
Pictures speak louder than words so I've added some for you to see just how easy it is.

The basic set up with the elements on each side of the antenna

A better view of how the elements are spread out from the base

And finally how the tapping was done with a simple screw, easy!

Overall I checked it against the cobweb as the moxon is currently in the lowered mode, it actually seemed quieter with roughly similar SWR readings. I think for some DX work it should be OK.

Thursday, March 16, 2017

Hustler changes and a Winch system for the Moxon

I’m currently working on upgrading my Hustler vertical antenna 6BTV to incorporate 17 and 24 meters. It’s a fairly easy upgrade, in which you tap in to the base of the antenna and fit the 12 and 24 meter elements. By extending out from the base by about a foot horizontally and then rising vertically parallel to the vertical tube hanging and from the top. I found the best idea was some was to attach some plastic tubing to the top and antenna by some zip cable and it seemed to do the trick.
My other project at the moment is building a winch for the main 30ft mast. Raising and lowering has been a physical effort for me and it can be quite precarious, it's right on the border of my lifting capabilities with the 17 meter Moxon and the rotator. So I decided on a winch system and have been planning for a while (see earlier post).
I was going to purchase one to save the bother of having to build, but the prices are not cheap, so I figured I could do just as well in constructing something just to get a light weight antenna raised to a moderate 30 feet. I was thinking about a pulley at the top of my two scaffolds poles, but I think an easier solution is to put it at the base instead, nothing about the physics more it's just easier to build!
Starting the winch build

It’s just two scaffolds pole about 8ft in length bolted together with a pulley at the base and the winch on a steel plate halfway up the poles. The cable from the winch runs down through the pulley to the base of the attached mast. On winching the base of the mast is pulled inwards towards the scaffold poles rotating and raising the mast. Simple but effective, the only hard bit will be digging out two and half feet of hole and mixing up some concrete!
The completed winch, simple but hopefully effective!
To be honest while I have been building the winch, I have noticed the light weight rotator with the Moxon has been playing up in the high winds by slipping at the point of its azimuth. Unfortunately there is no lock, so if I leave it facing SW direction sometimes end up with it facing north, which can get a wee bit confusing!

So it may have to come down at some stage while I put up a smaller Moxon or my 2 meter 6 element Yagi, I think the 17 meter one is slightly too big for the rotator, even in a light wind its seems to slip, which is annoying as it can get quite gusty up here.
This of course puts a downer on my purchasing a mini beam antenna, so I may just have to have another think at what's about and works for me. But I'll try something smaller first to see if that solves the issue.

Monday, March 6, 2017

What Yagi and Tilt Over Mast Designs

Continuation on a mini beam progresses and I’m thinking of purchasing a THF2-e Yagi, a two element tribander for 20, 21 and 10 meters. Reasonably priced at £360, the reviews have been pretty good and I think it would suit my needs. However it’s still early days yet so we’ll wait and see.
Currently the 17m Moxon is sitting in the horizontal position due to high winds. For the past few weeks I have been manually raising and lowering the antenna which can be quite tough, as it’s reasonably heavy with a 25’ scaffold pole, rotator and probably 8 kilos of antenna. So it does add up a bit and can be a bit of a struggle for one person!
I’m trying to design a winch system for a tilt over mast which would incorporate two 8’ scaffold poles positioned close together 2' deep in the ground, similar to what I have now with the main 25' mast between them which rotates with a bolt between all poles.
A winch will be attached to both or one of the poles, with a pulley at the top and winching would then pull the mast in an upward direction therefore saving my back!! All basic stuff but with a bit more planning and thinking should work OK.
Anyway I've already bought a 2500 lbs strain winch off eBay on the cheap and am now looking out for other bits and pieces that I may need. Everything will have to be strong and sturdy so welding as well as bolting will probably be incorporated. This might prove to be an interesting project but I'm sure there will be some good ideas on the web when I give it a good search.