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Old Dec 31, 2012, 04:46 PM
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Is there a recommended post mortem fix? e.g. use a shielded wire for the active. I used Romex 14-3 and stripped the insulation for the wires. (At least I got to try out my new soldering station)
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Old Dec 31, 2012, 08:27 PM
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I grabbed some coax stripped the outside sheath, removed the shield/foil, exposed the pin then hollowed around the pin so it would fit over the N chassis active feed. Then, I de-soldered the feed from the active, soldered the coax on the feed, trimmed to length and soldered the feed to the element. Is this sufficient to thwart a radiating feed?

Picard, thank you on the weather proofing.
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Old Dec 31, 2012, 08:29 PM
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Blainville, Quebec, Canada
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Quote:
Originally Posted by 1fullbird View Post
I grabbed some coax stripped the outside sheath, removed the shield/foil, exposed the pin then hollowed around the pin so it would fit over the N chassis active feed. Then, I de-soldered the feed from the active, soldered the coax on the feed, trimmed to length and soldered the feed to the element. Is this sufficient to thwart a radiating feed?

Picard, thank you on the weather proofing.
what you have to keep is the shield (foil) the plastic will let the wave pass like butter.
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Old Dec 31, 2012, 08:41 PM
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Got it. Thank you.

Updated picture of active feed with shielded cable. Is this sufficent to prevent the radiating feed? (unsure of the exposed center element of the N chassis at the point of origin?)
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Old Jan 13, 2013, 04:55 AM
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Ireland, Donegal, Convoy
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Can I use a 1.2mm galvanized steel for reflector?
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Old Jan 13, 2013, 09:59 AM
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^Yes. That's what I use.
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Old Jan 13, 2013, 10:00 AM
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Quote:
Originally Posted by 1fullbird View Post
Got it. Thank you.

Updated picture of active feed with shielded cable. Is this sufficent to prevent the radiating feed? (unsure of the exposed center element of the N chassis at the point of origin?)
You need to connect the wire to the shield at the feedpoint, not at the base or you end up with a unbalanced transmission line.

-Alex
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Old Jan 13, 2013, 02:05 PM
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Alex, Thank you. I have since built another one with the 1/4" copper pipe instead of the N chassis. It seemed to go easier. Had nothing to do with practice (right).
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Old Feb 07, 2013, 02:03 AM
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Alex, Thank you for making science as easy as anyone with shallow knowledge about electronics can deal with such important issue for FPV guys
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Old Feb 26, 2013, 12:30 PM
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A gust of wind decided to damage my biquad.
So I was facing the problem of where to get a copper tube to make a new one.

Destiny (or me as a bad pilot) put in my hands a broken skid pipe from a 450 heli. That thing is aluminium and scrapping the coating it seems to conduct energy quite well.
So I'm just wondering if that is ok to use? I suppose copper would be better but in lack of it.
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Old Feb 26, 2013, 01:52 PM
Foam Snow
South Africa, WC, Cape Town
Joined Aug 2011
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I tested my biquad today and was 5km out when my RTH kicked in, except there was a mountain below my plane, higher than the RTH altitude... I watched helplessly as my plane crashed into it.. and kept on watching it! 4.6km away, crashed into some bushes my inverted V touching the ground, I was still reading the OSD no problem!!

I'm so impressed with this design... thanks Alex.

If only my radio link was as robust... :/
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Old Feb 26, 2013, 10:30 PM
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United States, FL, Marco Island
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Sorry about your SW I also have a SW w RL and IBC DIY bi-quad (1280) and have been out over 13km with both still solid. I fly in a very noisy RF environment. You look like that area is pretty desolate unless there is a tower on that hill. I wonder why the failure at such a short distance. I have some Q's if you don't mind.
Did you do micro tests to make sure there was no onboard interference?
Were you able to monitior your RSSI? If so was there a gradual or sudden drop?
If you have a video of the flight I would like to view it.
It looks like your electronice are ok so I hope your back in the air soon!
My setup is in my blog. I appreciate your input.
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Old Feb 26, 2013, 11:36 PM
Foam Snow
South Africa, WC, Cape Town
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Quote:
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.. I have some Q's if you don't mind...
Thanks Picard, sent PM.
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Old Feb 27, 2013, 08:09 AM
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Quote:
Originally Posted by IceWind View Post
A gust of wind decided to damage my biquad.
So I was facing the problem of where to get a copper tube to make a new one.

Destiny (or me as a bad pilot) put in my hands a broken skid pipe from a 450 heli. That thing is aluminium and scrapping the coating it seems to conduct energy quite well.
So I'm just wondering if that is ok to use? I suppose copper would be better but in lack of it.
If you can solder it, it will work. In my tutorial, you will see I use no tube. I just folded over the coaxial cable shield. The tube is added in many people's builds for simplicity.

-Alex
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Old Mar 08, 2013, 07:09 PM
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Could one use stainless steel as the back ?
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