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Feek said:
Mast as been lowered, Hexbeam removed and I've started building the new mast top.

I've got the initial stub, the tilt plate, the SteppIR boom and then an extension pole with a new ADS-B aerial mounted on the top, that's 48 ft above the ground.

RiEr5a2.jpeg


Everything's all wired up, new coax on the aerial, controller cable etc, all with the new chokes and cables all tidied up nicely in the shack.

I've got one more step to do on the element housings but the aerial I've got is a slightly different version to the latest manual so I've been assembling it in a bit of a mixed fashion. Hoping to get the final brackets on this week with it all being completed next weekend.
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What’s the new ADSB antenna mate? How you finding it any better?
 
Feek said:
Mast as been lowered, Hexbeam removed and I've started building the new mast top.

I've got the initial stub, the tilt plate, the SteppIR boom and then an extension pole with a new ADS-B aerial mounted on the top, that's 48 ft above the ground.

RiEr5a2.jpeg


Everything's all wired up, new coax on the aerial, controller cable etc, all with the new chokes and cables all tidied up nicely in the shack.

I've got one more step to do on the element housings but the aerial I've got is a slightly different version to the latest manual so I've been assembling it in a bit of a mixed fashion. Hoping to get the final brackets on this week with it all being completed next weekend.
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Wish that I could have something like that, as it is have to make do with an end fed stuffed in the loft. Even so, I have now managed 2300 contacts on FT8 since April.
 
Erm yeah that’s hard to pick one said:
What’s the new ADSB antenna mate? How you finding it any better?
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It's a Vinnant CC1090/8-P as opposed to my previous Jettison A3 so allegedly a bit more gain. It's also 7 ft higher than the old aerial.

Yes, it seems better but it's very early to tell as it's only been a couple of days and I think there's been some enhanced conditions. I think I'm getting about 10nm further range and both aircraft seen/tracked seem higher. It'll take a few weeks to be sure.

13oots2 said:
Wish that I could have something like that, as it is have to make do with an end fed stuffed in the loft. Even so, I have now managed 2300 contacts on FT8 since April.
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As I keep saying, we're on our way to solar peak so things are just getting better all the time. I've been without any aerials for HF for about a month and I'm really struggling here so I have to get the SteppIR finished and up soon.

Have you been working exclusively FT8?
 
Feek said:
It's a Vinnant CC1090/8-P as opposed to my previous Jettison A3 so allegedly a bit more gain. It's also 7 ft higher than the old aerial.

Yes, it seems better but it's very early to tell as it's only been a couple of days and I think there's been some enhanced conditions. I think I'm getting about 10nm further range and both aircraft seen/tracked seem higher. It'll take a few weeks to be sure.
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Cheers for replying. I bought the CC1090/9-PSE from them back in June. Sadly I found my results were worse, a lot worse. I reached out to them and they did support.

Below should be some photos. I grabbed some cables whilst I was at it. The antenna did arrive damaged, the 2 sections had come apart on the white block with the glue cracking.










free image hosting site

I got my self a VNA to test and they said it was damaged in the transit shipping.





So I sent them the photos and I got this back

Hello dear
at this point I can confirm that antenna sufferes the transport damage as this SWR is not normal and it is useless to compare the faulty antenna to the functioning antenna .
I would proceede to the full refund if you agree,as frankly we dont have time to deal with this.We had some bad transport damage in Uk recently so we are not surprised.
Antenna took lot of battering and there is plenty things that can go bad when the radome is such rip opened.
Kind regards
Vinnant Slovakia Team
CEO Stanislav Palo
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I gutted as I was hoping it was to be all singing and dancing. Would be good if it could be fixed. Sorry for the large random post.
 
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It confirms that they are, as expected a multi-element colinear. I was originally considering the 9-PSE but they won't ship that to the UK any more due to previous problems with damage in transit. Clearly that's your fault ;)

It does look repairable though, you can see from each section how they're supposed to be connected. Get your soldering iron out!
 
What frequency range does that aerial operate on? I ask because the coax feedline looks very lossy for anything above at the most 28 MHz.

As Feek says, it does look as though th antenna could be repaired fairly easily. Araldite Rapidhas low dielectric loss if you need a reasonably strong multi substrate adhesive.
 
Feek said:
It confirms that they are, as expected a multi-element colinear. I was originally considering the 9-PSE but they won't ship that to the UK any more due to previous problems with damage in transit. Clearly that's your fault ;)

It does look repairable though, you can see from each section how they're supposed to be connected. Get your soldering iron out!
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Erm yeah that might be me. Was in June it happend. But nothing looks to be broken. I might take it apart and have a look but not 100% what I’m looking for.
Chris Wilson said:
What frequency range does that aerial operate on? I ask because the coax feedline looks very lossy for anything above at the most 28 MHz.

As Feek says, it does look as though th antenna could be repaired fairly easily. Araldite Rapidhas low dielectric loss if you need a reasonably strong multi substrate adhesive.
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1090mhz. The coax I bought from them is BELDEN H155. https://docs.rs-online.com/4f87/0900766b81603b8d.pdf
 
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Erm yeah that’s hard to pick one said:
But nothing looks to be broken. I might take it apart and have a look but not 100% what I’m looking for.
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Looks like you've already taken it apart? These two joints looks pretty iffy to me. The bottom part looks as though a strand is making contact but the higher one doesn't.

vrmNi4k.png


It's a coaxial colinear, the construction details are pretty straightforward but they're a real pain to make, and to make successfully because the measurements are so precise.

1D1usR7.png
 
The loss of that cable over 1GHz is dire, I would either use Andrew (now Commscope but reel ends are usually Andrew on Ebay) LDF4-50 or if possible get the receiever up by the antenna on a LAN (I know nothing about aircraft comms, so don't know what you use for this stuff...).



Your stuff has a loss of -30 dB at even 1000 MHz, LDF4-50 has a loss of -7.3 Db per 100 metres. Vast difference even on a shortish run.

I use LDF4-50 even for 28 MHz, the difference to top grade RG8 or similar is huge. I always thought 10 meters was dead until I ran a decent feeder.

I am always on the look out for part reels of LDF4-50 and genuine Andrew fittings.
 
Heliax is definitely overkill for 10m (maybe not so if you have a 300m run) and it's not the easiest thing to handle either. My ADS-B receiver is in a box at the top of the mast, I have a run of CAT6 up and power the receiver by PoE and have an 8m run of Hyperflex 10 up to the aerial. They quote 13.4dB loss at 1GHz so my short run is almost exactly 1dB. I can live with that.

Certainly wouldn't consider anything less though.

Also using Hyperflex 10 on the new aerial, a 30m length is just two thirds of a dB loss on 28MHz which I'm happy with.

I've had a 20m roll of 4-50 for years, never really found anywhere practical I can put it.

Chris Wilson said:
I always thought 10 meters was dead until I ran a decent feeder.
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It helps that cycle 25 is ramping up. In a few years time, you can have your receiver connected direct to the 10m aerial, it'll be dead ;)
 
Feek said:
Looks like you've already taken it apart? These two joints looks pretty iffy to me. The bottom part looks as though a strand is making contact but the higher one doesn't.

vrmNi4k.png


It's a coaxial colinear, the construction details are pretty straightforward but they're a real pain to make, and to make successfully because the measurements are so precise.

1D1usR7.png
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I’ve just taken it apart again and taken photos.




I also tasted with a multimeter for what I know. On the N connector centre pin to the outer screw element I get a short across them.
 
Erm yeah that’s hard to pick one said:
I also tasted with a multimeter for what I know. On the N connector centre pin to the outer screw element I get a short across them.
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Yeah, one of the pictures you showed has the centre connected to the braid at the top so I'd expect a short at DC.

If those connections are good (they look better from these new pictures but not fantastic) and the SWR is showing as 1.082:1 at 1090 MHz, I don't know why it's not working for you.
 
Nerdy post warning!! If it sounds easy, try something similar ;)

After several poor results the time signal PIPs from BBC4 ( IO82wh Droitwich/Mast A-B 500 kW ) were captured completely this morning by an acquaintance of mine in Tasmania, ( QE37pd ) over a distance of 17516 km.


r4-time-pips.jpg
 
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Chris Wilson said:
Nerdy post warning!! If it sounds easy, try something similar ;)

After several poor results the time signal PIPs from BBC4 ( IO82wh Droitwich/Mast A-B 500 kW ) were captured completely this morning by an acquaintance of mine in Tasmania, ( QE37pd ) over a distance of 17516 km.
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That's quite a feat, I'm guessing some sort of extensive beverage antenna? I wish I had the space or noise floor for MW/LW DX.
 
I think he used a modest active loop aerial, I use one for LF and it holds its own noise and sensitivity wise against my big horizontal quad wire loop which is circa 580 feet in circumference. Of course you can't transmit with an active loop.
 
For those times that low power is boring and you wish to make a "statement" on the airwaves this ad on a US amateur radio forum may offer the solution. (The guy's building a much bigger amp at the moment....) :)

*****************************

I designed this amp (back in 2007) for a buddy, who is now SK. Current owner is in MT. It uses a custom 253 lb Dahl plate xfmr and 24 x 3900uf lytics. Vac relays used for the input + cut off bias. Paralleled Jennings RJ2B's used for the output. We tested the manually tuned, tuned input with a 800 watt CCS cxr for 10 mins, on each band. Input swr is dead flat across all bands. Triple wafer model 85 switch used for the 12 kw PI net. Multronics MI-14 1/2" tubing coil used for 160-80-60-40-30m. HB 1/2 tubing coil used for 20-17-15-12m. This is a 9 band amp. 1000 pf @ 15 kv jennings tune cap. 3000 pf @ 5 kv jennings load cap. Bias is adjustable, on the fly with a 20 position rotary switch. Dual line section bird, with 25 kw forward slug and 1 kw reverse slug. Pep board also installed. Kicks offline if reflected power too high. 10 kw out with 500w of drive. 12 kw with 600 watts of drive. 7-16 DIN output connector. I also have a spare, nib blower, on my shelf. 253 lb dal xfmr has pri taps at 198-208-218 vac....and also 230-240-250 vac. Sec taps at 2300, 2900, 3900, 4600, 5000, 5400 vac. ( single phase 60 hz). 3 x 300 amp contactors used on the 240 vac input. One per each leg..and the 3rd one used for the step start. Separate step start and variac used for the fil xfmr. There is only 5600 hrs on the hour meter. You need 200 amp service...and also a 100 amp breaker installed in the main 200 amp panel...and a min of 3 ga copper wire from main panel to amp.
If interested, contact the seller below.

A SUPERBLY HAND BUILT 3CX-6000A7 HF AMPLIFIER IN A 6 FT RACK ON WHEELS. DESIGNED BY A PROFESSIONAL ENGINEER. PETER DAHL HV SUPPLY WITH TAPS DELIVERS UP TO 8000 VDC AT 3 AMPS. ANY TRANSCEIVER WITH A 500 WATT INTERMEDIATE AMP CAN PRODUCE OVER 10KW OUTPUT. INPUT AND OUTPUT BAND SWITCHES WITH TUNED PI NETWORKS FOR ALL HAM BANDS 160-12 METERS AND TUNABLE TO OTHER HF FREQUENCIES 3.5-24 MHZ. HUGE ADJUSTABLE OUTPUT VACUUM CAPS AND VACUUM RELAYS. ADJUSTABLE BIAS FOR BOTH LINEAR AND CLASS C. EXTENSIVE METERING, PROTECTION CIRCUITS AND FUSING THROUGHOUT. OVER $10,000 IN PARTS AT 2010 PRICES AND UNTOLD HOURS WERE SPENT BUILDING AND PERFECTING THIS INCREDIBLE MACHINE. WE CALL IT THE MONSTER AMP. ASKING $10,000 OR BEST OFFER. WE HAVE DETAILED PHOTOS. ONSITE DEMONSTRATION OF THIS AMP’S OPERATION AND CAPABILITES IS AVAILABLE IN MONTANA. TOO HEAVY TO SHIP. SERIOUS BUYERS CALL 406-240-5428 OR 406-830-6360 FOR MORE INFORMATION. NOTE: OPERATION HIGHER THAN 1500 WATTS IN US HAM BANDS VIOLATES FCC RULES.

*****************************

Hmm, my newly rebuilt generator would laugh at that, I wonder what `er indoors would say about the above in the spare room....? :)
 
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