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Author Topic: Up the discone!!  (Read 391 times)

Offline IQ_imbalance

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Up the discone!!
« on: May 15, 2020, 0010 UTC »
Today I started my little project to get some elevation on my DJ-130 discone.  Itís been mounted on a 2nd floor deck, but I want to try and raise it above the roofline if possible.

Its new home will be a tree so I broke out the fishing pole, lead sinker, and slingshot. I was pleasantly surprised to manage to get the line on a decent branch without the lead sinker breaking any windows or heads.  So far so good....

Next was to swap the 20lb test for something more substantial.  Unfortunately the 550 cord I thought I had was nowhere to be found beyond bits and pieces, but nowhere near the length necessary.  Amazon to the rescue, but that means itís in a holding pattern for now.
LOG/NE-SW unterminated BOG/DJ-130/800Mhz Yagi
AFEDRI SDR-Net ICF-SC1 SDS-200 various RTL-SDR
Central MD

Offline Brian

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Re: Up the discone!!
« Reply #1 on: May 15, 2020, 1144 UTC »
I lost many a lead sinker finding out what fishing line was the best to use. I'm sure my neighbour where I used to live wondered why he was finding all these weights in his garden  ???

Online Ray Lalleu

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Re: Up the discone!!
« Reply #2 on: May 17, 2020, 1704 UTC »
Rather than lead sinkers, use avocado kernels!
D/E/F/G/It/Sp : Dutch/English/French/German/Italian/Spanish
+/- : about 0.02 offset, ++/-- 0.03/0.04 offset
Balanced wire antennas, wire lines and ATU

Offline Brian

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Re: Up the discone!!
« Reply #3 on: May 17, 2020, 1925 UTC »
Rather than lead sinkers, use avocado kernels!

I don't like avocados  :)

I did eventually find the correct combination of line and weight. It's that long since I've to use it, over 10 years, that the rubber elastic on my catapult had rotted away.

Offline IQ_imbalance

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Re: Up the discone!!
« Reply #4 on: June 01, 2020, 1612 UTC »
Some additional data....apparently the DJ-130 can survive free fall from about 40' onto a deck.  20lb test line does NOT hold up well.

Good news though, the 550 cord arrived and i used it to hoist the antenna back up.  As long as the squirrels don't eat it, and the branch holds, I think i'm in a good place.

LOG/NE-SW unterminated BOG/DJ-130/800Mhz Yagi
AFEDRI SDR-Net ICF-SC1 SDS-200 various RTL-SDR
Central MD

Offline IQ_imbalance

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Re: Up the discone!!
« Reply #5 on: June 06, 2020, 0236 UTC »
another lesson learned.  550 cord is a great RF insulator while dry, but when it gets wet...not so much.  Was wondering why everything got quiet after a few rain showers....

Will install a PVC insulator to deal with this issue tomorrow.
LOG/NE-SW unterminated BOG/DJ-130/800Mhz Yagi
AFEDRI SDR-Net ICF-SC1 SDS-200 various RTL-SDR
Central MD

Offline IQ_imbalance

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Re: Up the discone!!
« Reply #6 on: June 06, 2020, 1752 UTC »
....and it wasn't the 550 cord.  Turns out i didn't waterproof my connectors adequately and while it works great at HF and VHF, it's practically deaf on UHF (~800MHz).  I can see a weak signal on my afedri but it's not nearly good enough for my scanner to decode.  Tried whacking a few feet of coax off the ends but still no-go.  Going to scrap the coax (no big deal, picked up several hundred feet for cheap) and start again once I get some additional coax-seal...apparently 'waterproof' F-connectors only do so much.....
LOG/NE-SW unterminated BOG/DJ-130/800Mhz Yagi
AFEDRI SDR-Net ICF-SC1 SDS-200 various RTL-SDR
Central MD