New (old) Imax 2000 ready for the roof.

In the last force 10 gale in spring my now 18 years old Imax 2000 hit the dust, rather the top section broke and fell off.

I still had 2 spares of which i now put one together, painted it white ( extra coat for protection of the fiberglass) new coax on it ( Sort of LMR 400 here it is aircom plus, used for uhf normally, but i had a roll left over.

The old one and new one will be used on 15 , 12 , and 10, though 17 meters will work as well, need a tuner there since the swr there is 1:3, the rest of the bands is used without the need of a tuner.

I don't use 11 meter though.
So a cheap and cheerfull 4 band vertical that works, WAC on 10 meter with it, as on 12 and 15 10 years back when the conditions were good.

The old one saw windspeeds up to 120+ Km/H where the most part of the antenna was more horizontal as vertical......

The fiberglass loses it's bonding through the U.V., leading to de lamination, and the top will break, the extra coat of very strong white paint on the new one.

So in the next week i will carry my old carcass up the slanted roof, remove the remnants of the old one including old coax and mount the new one, if that survives another 18 years i'll probably be gone...
:icon_rolleyes:

Post results when they become available.

Waiting for a good dry day, still some rain showers here, looks better at the end of the week, back to 20+ C and sunny.
Getting on rooftiles when wet is not safe.....
Tested the antenna on a pole in the backyard working from 17 meter ( tuner 1:3) and without tuner 15, 12, 11, 10.
Worked spain on 15 meter while it was 2 meter off the ground, on the roof it will be free standing 11 meter from the ground.

I've had one as my 10-17M antenna for a number of years. Installed with the base about 30ft up. Works well.

It's up, since yesterday, had a dry day 18 C, so hauled my almost 68 year old ass and antenna and coax up, removed the old crap including coax, and put the refurbished one up, now i have only one spare Imax 2000 left ;)
Works fine, very low loss coax on it, SWR on 10 around 1: 1.2, 11 meter 1:1.4, 12 meter 1:1.6, 15 meter 1; 1.8, 17 meter 1:2.8, 20 meter 1:4 last 2 bands workable with tuner.

On 20 meter reception isn't too far off the OCF from fritzel, sometimes a tad better, sometimes a tad less.
The OCF also works on 17 though 1:1, so the goal was to get 15/12/10 working well which i got.
No radials used, just some ferrite clamps around the coax at the feed point, the mast of 7 feet and steel cables around the concrete chimney work as "counterpoise" it seems.
Feedpoint is 11 meter of the ground, or about 35 feet.

Very white with the coat of paint on it though... shiny as well, flopping around happily.:hahano:

Fun...
Sporadic E opening, on 10, Sardinia, and Spain, 5 9+ signals on the vertical given and received with my 200 watts from the FT 2000 D.
Have to go out now, pity with that opening...

Next project, getting the Diamond X 510 on the roof, need to find a few clamps for a small mast of 7 feet.
The Diamond discone works, but has no gain...
With the X 510N on the roof my range will be double of the discone, or 50 to 70 miles, reaching 1/2 the country's repeaters, and if there are conditions it works fine with 50 watts SSB as well.

Those are rather impressive antennas, especially the Diamond. I know you'll have good luck with them, a fact is better than a wish. I have used marine epoxy paint made for fiberglass boat hulls and it lasted indefinitely.

Same polyester paint was used on the Imax 2000, and the polyester mast for the Diamond X 510 N, 2 army sections on 1. 1/2 inch polyester sticks used to hold up camo, 2 sticks is 2.40 meter above the roof, meaning 11.60 meters the X 510 will have the radials, so top section at 16.80 meters above ground. ( just over 55 feet)
Have two bottom sections of the Imax spare, and a complete one, and a spare top section as well.
Just tested the Ecoflex 15 coax i had laying around, all of 16 meters which was used on the 6 meter beam.
Waiting for a dry moment to test the X 510 N on the ground before i haul it up.
Wil be in the weekend, rain expected the next days.
Loss of the coax is 0.5 DB on 2 and 0.8 DB on 70.
https://www.universal-radio.com/cata.../4130spec.html
Cost now 7 euro's a meter, when i bought it 14 years back it was 3.50 Euro a meter...
Tested it for losses, still as new.
Still have 2 lengths spare each 23 meters, (79 feet) former 2/70 beams.
So using up old supply, hope it will provide x years fun.

Sorting to my old antenna stuff i found enough stuff to make two cross clamps to mount the x510 N mast to the 2 stainless steel bars around the chimney. 50x 50 mm L sections of 316 SS with stainless steel threads clamped around the concrete chimney that held up the mast with the 6/2/70 beams.
Just some drilling new holes and some measuring to do.
Keeps me off the street

Good day to put it on the roof, sunny, 21 C and next week 30+... so will be putting the X 510N on the roof today with new mast and coax.

Well, sorted, up and away, SWR on 2/70 nowhere worse as 1: 1.4
See ( hopefully) attachment, from left to right, Imax 2000, 77 feet vertical for 160 - 20 with autotuner fed then Diamond X 510N

Another piccie

Be safe young man!

Yeah, the heart is young, pity my back and muscles don't agree with it....:yuck:
I have to climb out of the little window, 1 foot square, pull up some tiles to make a "ladder" till i reach the roof top.
Handling an 5.2 meter long antenna standing on a roof tile and chimney isn't that funny at my age...
It helps being 1 inch shy of 7 feet tall though.:mrgreen:

Gigantic and brass. Clang clang!:rock:

I rather think they shriveled a bit standing up there...:mrgreen:

Calculated the antenna/fed syatem
Gain antenna on 2 meter 8.5 DBi, 70 11.7DBi
Real gain 6.3DBd and 9.4DBd
Coax losses 16 meters including N connectors
0.544 for 2 meter, 0.976 for 70 cm's
Leaves 2 meters gain 5.8 DBd, 70 8.31 DBd gain at the transceiver.

Just for giggles...
Most repeaters up to 30 miles S9+40, repeaters up to 60 miles S9.
Local hams up to 70 miles with 50 watts FM, 90 miles with SSB.
This IS a flat pancake country.... :mrgreen:

Ah, you lucked out with the terrain. I'm down in a valley.

I'm sure you're happy the antenna project is finished with some great results. Lucky you living in a pancake country, just keep those pumps running. (;->) The flying public doesn't know what I know having worked 7 years at Newark (NJ) International Airport, it's 2 meters below sea level built on a filled in swamp, is surrounded by a moat and has a pumping station that runs 24/7/365.

Water out of the way, I live on a sandy pancake that is NJ below Raritan Bay so I've had similar experiences but not the range you have on 2M and 70cM before becoming a paper ham. On the latter band the only activity was on the NJ Network of repeaters that covered the entire state and into southeast Pennsylvania, target areas selected by DTMF tones. The thing that irked me about 2M was nobody within FM simplex range wanted to move off the repeaters. I mean when you have a group where everybody is within simplex range of each other why tie up the repeater? Then there is SSB that nobody used except during troposphereic band openings, and along our Atlantic coast they are legendary. The difference I see since you only have vertical antennas is you can work other SSB stations vertically, here every mode except FM being vertical for mobiles is horizontal. I having had no horizontal antennas couldn't work SSB except one time I found two stations near New York City using vertical... and so it goes on the sandy pancake.

We Dutch have 2000 years experience how to keep our feet dry, and that has become an export hit as well.. ;)
I used to have up there a 5 element 6 meter beam, a 12 element flexa yagi for 2 meter and a 23 element flexa yagi for 70 cm's and on top of that was the X 510N.

3 years back after storm number xxx i took it all down, the clamps around the chimney are 2"by 2" 316 Stainless steel with S.S. thread ends holding it together, but the antenna's needed maintenance and i was becoming older and have to do things alone up there.. so I ended my time of 15 years of having beams up there, and working all Europe the middle east and North Africa on most of the bands from 6 meter up.

Here up north of the country it IS flat, so a good gain vertical freestanding has some punch, even for direct contacts on 2/70.
If there are conditions i will hit them and not miss them as is possible with a beam in the wrong direction, and after the first reflection the polarization can be anything as it is with a beam.

With the gain low at the horizon with the vertical like with a beam I don't miss much, for 50 MHz i use the FD-4 off center fed which does quite fine there with it's 140 feet length at 12 meters above ground, this one with coil and added wire at the short end is also in resonance at 1850 or 160 meters and usable on most HF bands, with the 23 meter vertical and autotunerMFJ 998 i can chose from 160 to 20 between horizontal and vertical, 18 15 12 and 10 the Imax vertical or OCF as well.

I have the Yaesu FT 847 with Collins filters, and my modifications, the Yaesu FT 100 mobile rig 160 - 70, and the FT 2000 - D and Heathkit SB 1000 with rebuild innards and new 3-500ZG tube.
I have the luck the ground here is young silty sea clay, so that helps in far field gain and reflections and good ground as with 3000 feet of copper radials in/on the ground.

Last thing to do on the roof is to replace the bend stick holding up the balun of the OCF .... just need to make new clamps for it the next weeks, i have enough polyester sticks left to make something nice of that and straight....and painted white :mrgreen:
Lots of lakes and canals here, so quite nice for tourists and flat country.
Lots of repeaters as well, though i prefer working directly.
Several repeater systems are coupled to each other forming a very large network so you can be working the whole country andbpart of Germany, the coversity project.
Remember i live on a plot between other houses of 30 x 7 meters.. 90 times 20 feet.

Also one of the reasons i don't do digital modes, just phone.:icon_rolleyes:

Any updates?

Please don't turn your roof into an antenna farm. (;->) We call these porcupines and the ham owners whackers.

Attachment 17525

Quote:

---

Originally Posted by kb2vxa

Please don't turn your roof into an antenna farm. (;->) We call these porcupines and the ham owners whackers.

Attachment 17525

---

It looks like those magmounts are the only thing holding the fenders and hood on the car...

Quote:

---

Originally Posted by kb2vxa

Please don't turn your roof into an antenna farm. (;->) We call these porcupines and the ham owners whackers.

Attachment 17525

---

All those magnets, and I think I see a thru-the-glass mount on the back window.

He didn't want to drill holes in that POS? :wtf: :squint: Love the duct tape job on the front bumper...:idea:

Imax 2K working fine, 10/11/12/15/18, 18 needs tuner help 1:2.2 or so.
Already worked the world round on 15 in FT-8 ausies New Zealand China, Thailand South Africa, South America, USA, canada just need 4 states to have worked all USA states.
On 10 a few nice ones when the band was a bit open.
Running 18 meters very low loss Aircom + to it, overkill coax but hey it was here to be used...
Tried Amplifier, Heathkit SB 1000 running 800 watts on 15 , 12 , 10 working fine as the old one did.
SWR on the bands lower as 1: 1.5 worst swr, most 1: 1.2.

There's a bumper under that duct tape? Rest assured in a few months that tape weathered off and he regretted using indoor tape outdoors. You mean hedidn't want to put MORE holes in it, you're looking right at one. That was Dayton 2008, I was there in 2000 IIRC the last one before the roof fell in, no porkies to be seen BUT I just HAD to get a picture of my evil twin brother. I was SO embarrassed, point, shoot, split!

So Cor you're doing fine with the newly repaired Imax, that's GREAT! According to NAVPERS, US Navy radio training manuals I had back in the day, tube transmitters with pi network outputs tolerated well SWR up to 3:1. Well, if it's military it's built to withstand an atomic bomb! My last job was electrical quality control in process and final for a company making magnetic components, transformers, chokes, etc. for military applications, you wouldn't believe how tight tolerances are. I wouldn't worry about a 1:1.5 SWR, that's only a 50 ohm transmitter looking into a 75 ohm load like a dipole. Using a trusty Bird 43 in line watt meter you see actual forward and reflected watts, then use the SWR conversion chart if that really matters.

Quote:

---

Originally Posted by kb2vxa

That was Dayton 2008.

---

I have a few pics of it and similar vehicles from the 2004-2015 Dayton era. One of the locals also has a car festooned with at least a couple dozen antennas. The guy is into 2-way radio in a professional capacity and as a prospective customer I'd run in the opposite direction were that vehicle to pull in to my facility for purposes of a quote.

Daiwa CN 801 real PEP reading meter used modified so it shows SWR also in pep mode.
The Heathkit doesn't care on 18 with that SWR, i watch the current back off a little and let it rip, the new 3-500ZG gets nice red during the work.
On the 77 feet high vertical i use the MFJ998 legal limit autotuner for 160 to 20.
So i have on all HF bands the choice of vertical or horizontal antenna use with the Fritzel FD-4 with coil and wire on the short end for 160 to 6 meters.
My roof did look like a porcupine several verticals, 23 element 70 cm beam 12 element 2 meter beam 5 element 6 meter beam, took the beams down getting too old to maintain them and rotor and bearings.
Will add omnidirectional 2/70 horizontal antenna this summer, then i'm done, the Diamond X 510 N works fine in FT 8 but i need horizontal for SSB on 2/70.

Pictures on qrz.com from he old situation.