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Old Apr 08, 2011, 12:07 PM
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Originally Posted by IBCrazy View Post
Well, it's not a sync I don't think. Total loss of signal (static) at 600 feet away. I will try connecting it to an old TV.

I'm not the only one who has this problem either. Many have reported the SPW does not work with airwave 5.8GHz modules. That's why I avoid all the confusion of "it doesn't work" and post the issue.

-Alex
so the question remains open?!
OMM has lawmates that work with SPW and IBCrazy has som that don't

IBCrazy, as I understand, you use lawmate with spw on tx and helical on rx, for 1.3?

OMM - what frequency are you on?
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Old Apr 08, 2011, 12:32 PM
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Amherst, VA
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Originally Posted by aSa2 View Post
so the question remains open?!
OMM has lawmates that work with SPW and IBCrazy has som that don't

IBCrazy, as I understand, you use lawmate with spw on tx and helical on rx, for 1.3?
Yes I fly the SPW on the plane and a helical on the ground. It works very well.

I tend to err on the side of caution in most of my posts. However, if it you have to decide between me and OMM, take OMM's advice over mine. He knows more than I do... far more.

-Alex
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Old Apr 08, 2011, 01:06 PM
QiW
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south east asia
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after bending some wires to get the approximate size of the SPW and CL ... i think i will just go with the Vee 1st
on my 900mhz setup the size of the SPW or the CL is just too cumbersome to put on the plane (cloudsfly glider)
it will just have to wait for me to get a 5.8 video setup

btw off topic .. tested the Vee with stock whip RX in the house earlier .. very very good results walking around with the goggles ... almost perfect video .. beats the crap out of the stock whip Tx antenna ... will be taking it out for a flight tomorrow
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Old Apr 08, 2011, 05:40 PM
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Quote:
Originally Posted by aSa2 View Post
..OMM - what frequency are you on?
1280 Mhz (the only legal frequency for ham radio license)


Quote:
Originally Posted by IBCrazy View Post
....I tend to err on the side of caution in most of my posts. However, if it you have to decide between me and OMM, take OMM's advice over mine. He knows more than I do... far more.

-Alex
That's a very nice compliment, Alex. However, even though it should not be a problem and I don't see it here, that does not mean there isn't a problem with your system that can be fixed. I know that you take care in your testing so we must be missing something. It is always interesting to find the root cause of something that does not make sense at a theoretical level. Here are a few other ideas:

1) Perhaps some lawmate RX units have an RF input that does not block DC and somehow there is a voltage across the antenna input that gets shorted with a grounded antenna like the SPW. That might take down the overall voltage enough to cause problems with the video output. I'm reaching here but it might be worth a quick check with the voltmeter to see if there is any voltage at the antenna input.

2) RF interference geting into the digitizer either from the nearby TX or receiver self oscillation. You could try testing with attenuation pads on both RX and TX to see if things change.

3) Video and Sync levels which are not processed correctly by the digitizer. I still think this is the most likely issue. It will be most interesting to hear what results you get with an analog monitor.

Whatever the cause, it would drive me crazy until I found the root problem. The biggest concern is that it could be an indication of something marginal that could eventually show up even with antennas that are now working OK with your system.

OMM
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Old Apr 09, 2011, 02:48 PM
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Quote:
Originally Posted by Old Man Mike View Post
1280 Mhz (the only legal frequency for ham radio license)
Actually, that might not be the case anymore. I tested a VTx with a 1256MHz channel! I also have an RX with that channel too. Just barely inside of the HAM spectrum.

-Alex
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Old Apr 11, 2011, 11:41 AM
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Flew out to 3.25 miles on my SPW and 5 turn helical at 1280 mhz this weekend. No range record, but great video and had fun! If I had a plane that could make it, i'm sure it could go MUCH farther.
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Old Apr 11, 2011, 11:58 AM
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Originally Posted by Derek_S View Post
Flew out to 3.25 miles on my SPW and 5 turn helical at 1280 mhz this weekend. No range record, but great video and had fun! If I had a plane that could make it, i'm sure it could go MUCH farther.
And you never tuned yours either
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Old Apr 12, 2011, 09:20 AM
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No, really dont have to for my kind of flying I guess. Seriously though, I would have to really figure out how to get something to fly longer to be able to outrange my home made antennas that you designed.

It looks like I have moved on from the part of my FPV experience where I try to get the best video range and quality, now I need to ponder on what plane I can keep in the air for 45+ minutes...
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Old Apr 15, 2011, 12:43 PM
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Birmingham AL
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OK IBCrazy, this is the Antenna I am about to buy (i think), first of all I was told (by you I think) that having a long co-ax going to the antenna is BAD, but this one has it, (my patch has a 2' one as well)
http://www.boostervision.com/cart/sc...?idProduct=122


first of all I am running 900mhz. I have a good 3dbi whip antenna on 1 Rx and a 9 dbi patch on the other reciever. and a v pole on the rx I was about to buy a 5 dbi magnetinc base whip to replace the 3 dbi. Would I be better off just making a clover leaf? I was wondering if I have a circular polarity clover on 1 rx, patch on the 2nd rx and a v-pole on the tx would it work well? what about is I put a clover leaf on the Tx , would my standard patch antenna on the rx still work well with the CP antenna on the tx? I don't know about mixing types of polarity and if the circular will still work well with the linear polarity antennas on the rest of my setup?
What would be the best and cheapest/easiest upgrades to do with antennas on m,y current setup?

like I said I have a 8dbi patch on 1 900mhz rx, a 3 dbi whip on the second 900mhz Rx. and an oracle between them. And I have a V-pole (or several stock omni-pole whips) for my tx's (1x 500mw and 1x 200mw) What is the best upgrade and can I just switch out half of the diversity set up to circular polarity clover on 1 of the rx's. Do I need to put one on the rx and the Tx? or am I better off just getting the bigger whip antenna and sticking with my current setup.? please help me IBCrazy or I will be too! lol
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Old Apr 19, 2011, 09:18 PM
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So if each lobe when laid flat intersects the center at around 105 degrees, and each ground leg is separated by 90 degrees, when looking down from the top, where should the + leg be in relation to the next ground leg? Should they be right over each other? 5-10 degrees of overlap?
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Old Apr 20, 2011, 03:25 AM
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angle of meet

I have been trying to make a jig for a 5.8 version and found this calculator useful as you can enter the degrees and establish the arc length (in our case 1/2 wavelength

http://www.analyzemath.com/Geometry_...ea_sector.html

the angle for a 1/4 wavelength of 13 mm is around 115 degrees

hope this is of use

pme
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Old Apr 20, 2011, 06:45 AM
Don't leave it Stock
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I stopped by Hobby Lobby (craft store) looking for the memory wire. Are we talking the gold colored wire?? That is solderable?? Anyone got a snap or sku #?/ Thanks
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Old Apr 20, 2011, 07:50 AM
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Quote:
Originally Posted by chrisercgr View Post
I have been trying to make a jig for a 5.8 version and found this calculator useful as you can enter the degrees and establish the arc length (in our case 1/2 wavelength

http://www.analyzemath.com/Geometry_...ea_sector.html

the angle for a 1/4 wavelength of 13 mm is around 115 degrees

hope this is of use

pme
Lots of people are making jigs, but I find hand forming faster, oddly. I bend the wire around a marker

Here's how I do it: I run the wire through a home-made wire straightener which is nothing more than a set of two rollers and a block of wood with a hole in it. The straightener looks just like a mig welder wire feed with a spring tesnioner to keep the rool from unreeling except it's wood.

The straightened wire gets marked at 1/4 wave, 3/4 wave and 1 wavelength and then gets cut off the spool. I then take the wire and wrap it around a round former. For 2.4GHz, I use a 1" PVC pipe glued to a peice of pywood with a weight on it (to keep it from moving). 5.8GHz I simply wrap around a marker in my hand. I actually over bend the wire, then pull lightly on the ends to de-stress the curve to exactly where I want it. I then grab the wire at the 1/4 wave marks with pliers and bend it.

To solder, I lay the forms against a couple of carpenter's speed squares. Magnets help hold the wire where I want it. Then I simply reach insert my cable and solder it all up.

-Alex
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Old May 13, 2011, 01:32 AM
Time's fun when ya havin flies
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Qld, AU
Joined Sep 2007
445 Posts
For what It's worth...
I made a set of CP's for my 5.8Ghz parkflier, hope to try them tomorrow.
I worked this template out to help with bending, might be useful to someone.
If the antennae perform well I'll post pics.
Cheers !
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Old May 14, 2011, 04:32 AM
There's magic in those wings !
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Joined Nov 2006
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deleted ... I couldn't ask the right question ?? I'll post again when I know the right question to ask

Thanks IBCrazy for the info in your blog and in aerial video systems

Khaled
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