Posts Tagged ‘Antenna projects’
If at first you don’t succeed try try again!
Well, here we are once again trying to get the portable ham radio setup going.
My first attempt was to place one of my mono band whips on my bike and set out a counter poise. It was with mixed results, the SWR was sometimes all over, there was a TX error message now and again on my KX3 and basically frustration trying to get it to work. So if at first you don’t succeed try try again.
Last week I was online searching again for another way to get my portable op’s on the air. I was looking for something that was easy to deploy, was portable and worked!
My interest has gone toward the Endfed antennas. I was looking at LNR’s antennas and then I came across the Endfed 40-6m antenna by Steve W1SFR. I shot him some questions regarding the antenna and he got back to me right away with the answers. His Endfed seems to be very well built using Wireman “silky” 18 gauge wire which I have used in the past and been very happy with. There was a nice noticeable quality in both the wire connections and the 9:1 unUn.
The antenna is only 35 feet but you do need about 25 feet of coax to act as a counter poise. Also your rig needs to have an antenna tuner (mine does) to get the benefit of 6m-40m with only a 35′ antenna and no traps. Also it was nice to see on his web site a link to purchase his antenna including shipping to VE3 land.
The shipping was super reasonable the total came to 67.00 U.S. Steve also mentions that his price includes handling as well. Other sites I had gone to being very interested in their antenna to only find out the shipping at times was either 1/2 or more of the price of the antenna.
There was lots of positive reviews on Eham about Steve’s antenna as well. I put some items I am not using in the shack sold them very fast and the funds were in place so I have placed my order and waiting for it to arrive.
I have the 25′ of coax on hand but I do have to head out to the hardware store for some rope 1/8″ nylon rope. Then I’m thinking of placing a water bottle with some sand it it as a weight to get the rope up and over a tree branch…..that is going to take some practice!
A slight change of plans…..
The test setup |
A brief overview of my MFJ 1788 loop antenna.
The antenna |
1. Very small foot print for an antenna that will give you 15m to 40m.
2. The antenna can be used mounted horizontally or vertically.
3. Once you get used to the tuning it's very fast and easy to tune.
4. I covered my antenna with as to keep it low profile and it works no problem with the cover.
5. The antenna remote control can operate either on AC or batteries.
6. Can be mounted on a simple tri-pod.
Some of the draw backs
1. The quality of the antenna is low, I had to make some adjustments to make it work as it should.
2. The band width is narrow and retuning has to be down often.
3. The SWR meter in the remote control unit is not very reliable.
4. Buzzer used to tell you the coarse tuning has finished is VERY hard to hear.
Repairing Cap spacing |
On air results with this antenna have been good, with regards to receiving I have been able to hear the Middle East, South Pacific, Europe, South America and of coarse North America. Now hearing a station and contacting the station is another ball of wax. With my power restrictions I have made some very satisfying contacts. My modest signal has made it into South America, all parts of Europe, Iceland and Africa so far. There are two Loop antennas that MFJ makes and if I was to make the choice again I would had gone with the MFJ 1786 as it covers 10m to 30m. I have found with this antenna there is no way to tune it below 15m. The characteristic of the tuning capacitor will not allow it. I have read the MFJ 1788 is like a wet noodle on 40m and it's true I have not been able to make it into the U.S. The MFJ 1786 would had been a better choice with more band opportunities.
SWR up’s and down’s
LP-100 reading |
K3 meter |
Final repairs on MFJ loop
Time to repair the control box. |
Ready to remove switch |
A great tool to have |
The MFJ 1788 loop arrives!
Ready for inspection |
Capacitor |
Control box test |
1. Send the control box back to either MFJ or DX Engineering for repairs?
2. Ask MFJ if it's possible to make the repair myself if they were to send me the part?
I settled on option 2 as I could still use the control box until the switch arrived and not be put on hold until control box was repaired or replaced. (note: I purchased DX Engineering's last unit)
Stepper motor |
All was going well until the capacitor was rotating counter clockwise and it just stopped! I then rotated the capacitor in the clockwise direction and back counter clockwise and it worked just fine. After many back and forth rotations the capacitor never acted up…..maybe this was a one off. I emailed MFJ regarding the switch and they are going to mail one to me so I can do the repair. Next is to mount the antenna and see how it performs stay tuned!
The reverse beacon network is KILLING ME!!!!!
The loop horizontal and nothing. |