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#1
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Rob, when you really done it, it ain't bragging.
There are thousands - maybe 10's of thousands - of Jim's antennas flying. He wrote the book on hidden aircraft antennas. Your information is might be a reasonable extrapolation, but his is empirical. On Thu, 27 Nov 2003 08:04:37 +0100, "Rob Turk" wrote: :Jim, : :I'm truely disappointed about your response. If this newsgroup is about :showing off how big your dick is, go right ahead. I was under the impression :that the newsgroup was to discuss and provide help. None of the information :I gave is wrong, I provided a fair warning to think twice before putting a :UHF antenna enclosed inside a frame. You made it into a ****ing match. I :admire the knowledge you have, but the way you display it makes me sick. : :Rob ![]() :mistakes...). : :"Jim Weir" wrote in message .. . : "Rob Turk" : shared these priceless pearls of wisdom: : : -"Jim Weir" wrote in message : .. . : - Are you guessing on this, repeating an OWT, or do you have first hand :hard : -data? : - : - Jim : - : - : -As a licensed ham operator : : Jesus. A ham operator? Those are the credentials you come to the table :with? : : Amateur radio extra, first licensed in 1959. First 'phone with radar : endorsement, 1960. BS-Physics (Microwave option) 1967. MSEE CGS 1983, RF : option. Pacific Southwest Airlines (1963-1967) avionics and radar :technician. : Teledyne Ryan Space Systems (1967-1973) Microwave Antenna Engineer. :Founder and : CEO RST Engineering, with a world class reputation for hidden antennas in : nonconductive structures (1973 --) with approximately fifteen THOUSAND ![]() : antennas in plastic/wood/fabric aircraft including one hanging in the : Smithsonian. : : : I have sufficient experience with frequencies : -around 1200 MHz. : : How long has it been since you fell off the turnip truck, feller? The ham :bands : at 33 and 23 cm are 10% or so away from the transponder frequencies. Not :too : far away, but far enough. : : : : Those don't like their antenna's shielded by wet or painted : -surfaces. : : First, the plural is "antennas", not the possessive. In the second place, :this : is the first mistake of fact so far. That is just horsepuckey. Wet and ![]() : won't make squat for difference. And I've done and retained the :engineering : data that says so. : : : Transponders are just over 1000MHz : : 1030 and 1090 to be exact. Betcha can't tell me without looking which one :is : transmit and which one is receive. : : : : , it's reasonably safe to assume : -they are equally influenced. I'm not saying it will never work (fwiw, :GSM at : -900MHz works in-door), but I do want to caution people that there are :many : -variables involved that could make it not work. : : Yada, yada yada... : : : - : -Contrary to COM signals (118-136MHz) you can't use just any CB or VHF :SWR : -meter to check out if the antenna matches at these frequencies. With the : -transponder sending out pulses of 200+ Watts I wouldn't want to gamble : -having a bad SWR and seeing that power end up ruining the transponder :stage. : -Better be safe and put the $22 antenna where it belongs; Outside. : : : Izzat a fact? Then I guess I'd best trash my $50k worth of RF antenna :test : equipment, because I surely wouldn't want to gamble my transponder on :brothers : Hewlett and Packard's equipment and the results derived therefrom. : : By the way, do the math before you post. That 200+ watts of transponder ![]() : is peak pulse power. If you go through the calculation, you find that the : transponder output stage is running about 5 watts CW averaged over a :couple of : seconds or so. : : Now, to repeat what I've been telling my colleagues building airplanes for :the : last 30 years...put the transponder antenna inside the plastic with a :round or : (better yet) octagonal ground plane, shield the sensitive parts of your :anatomy : with tinfoil, and go for it. : : Jim : : : Jim Weir (A&P/IA, CFI, & other good alphabet soup) : VP Eng RST Pres. Cyberchapter EAA Tech. Counselor : http://www.rst-engr.com : |
#2
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Here's my view of what happened:
1. Someone advises to just put the transponder antenna inside the frame. 2. I place a warning, basically saying there's more to it then just put it in and forget about it. 3. Jim comes back and asks if I have any experience at all that supports my warning, in a somewhat hostile way. 4. I respond that in my experience as ham operator I do have hands-on experience working with this. I caution the group (not Jim..) that diagnosis is harder than hooking up a cheap SWR meter. 5. Jim feels it necessary to dismiss my experience as bullsh*t, posts his entire resume, posts his list of valuable equipment and bashes my spelling. Nowhere did I say Jim was wrong. His 15.000 installed antennas certainly prove it can be done. But that doesn't dismiss that an unknowing home builder might make mistakes. The builder, or a follow-on owner may decide it's fancy to put metallic paint on the plane. Or someone may think it's a good idea to install an inspection hole next to the antenna, and use one of these aluminum covers. Both will influence proper operation of the transponder. I think Jim's response is way out of proportion. I know Jim has plenty of knowledge on the subject and I'm sure he'll agree that you can't just stick the antenna anywhere you want without thinking things through. Therefor I would have expected constructive comments from him, not all-out bashing. Rob wrote in message news ![]() Rob, when you really done it, it ain't bragging. There are thousands - maybe 10's of thousands - of Jim's antennas flying. He wrote the book on hidden aircraft antennas. Your information is might be a reasonable extrapolation, but his is empirical. On Thu, 27 Nov 2003 08:04:37 +0100, "Rob Turk" wrote: :Jim, : :I'm truely disappointed about your response. If this newsgroup is about :showing off how big your dick is, go right ahead. I was under the impression :that the newsgroup was to discuss and provide help. None of the information :I gave is wrong, I provided a fair warning to think twice before putting a :UHF antenna enclosed inside a frame. You made it into a ****ing match. I :admire the knowledge you have, but the way you display it makes me sick. : :Rob ![]() :mistakes...). : :"Jim Weir" wrote in message .. . : "Rob Turk" : shared these priceless pearls of wisdom: : : -"Jim Weir" wrote in message : .. . : - Are you guessing on this, repeating an OWT, or do you have first hand :hard : -data? : - : - Jim : - : - : -As a licensed ham operator : : Jesus. A ham operator? Those are the credentials you come to the table :with? : : Amateur radio extra, first licensed in 1959. First 'phone with radar : endorsement, 1960. BS-Physics (Microwave option) 1967. MSEE CGS 1983, RF : option. Pacific Southwest Airlines (1963-1967) avionics and radar :technician. : Teledyne Ryan Space Systems (1967-1973) Microwave Antenna Engineer. :Founder and : CEO RST Engineering, with a world class reputation for hidden antennas in : nonconductive structures (1973 --) with approximately fifteen THOUSAND ![]() : antennas in plastic/wood/fabric aircraft including one hanging in the : Smithsonian. : : : I have sufficient experience with frequencies : -around 1200 MHz. : : How long has it been since you fell off the turnip truck, feller? The ham :bands : at 33 and 23 cm are 10% or so away from the transponder frequencies. Not :too : far away, but far enough. : : : : Those don't like their antenna's shielded by wet or painted : -surfaces. : : First, the plural is "antennas", not the possessive. In the second place, :this : is the first mistake of fact so far. That is just horsepuckey. Wet and ![]() : won't make squat for difference. And I've done and retained the :engineering : data that says so. : : : Transponders are just over 1000MHz : : 1030 and 1090 to be exact. Betcha can't tell me without looking which one :is : transmit and which one is receive. : : : : , it's reasonably safe to assume : -they are equally influenced. I'm not saying it will never work (fwiw, :GSM at : -900MHz works in-door), but I do want to caution people that there are :many : -variables involved that could make it not work. : : Yada, yada yada... : : : - : -Contrary to COM signals (118-136MHz) you can't use just any CB or VHF :SWR : -meter to check out if the antenna matches at these frequencies. With the : -transponder sending out pulses of 200+ Watts I wouldn't want to gamble : -having a bad SWR and seeing that power end up ruining the transponder :stage. : -Better be safe and put the $22 antenna where it belongs; Outside. : : : Izzat a fact? Then I guess I'd best trash my $50k worth of RF antenna :test : equipment, because I surely wouldn't want to gamble my transponder on :brothers : Hewlett and Packard's equipment and the results derived therefrom. : : By the way, do the math before you post. That 200+ watts of transponder ![]() : is peak pulse power. If you go through the calculation, you find that the : transponder output stage is running about 5 watts CW averaged over a :couple of : seconds or so. : : Now, to repeat what I've been telling my colleagues building airplanes for :the : last 30 years...put the transponder antenna inside the plastic with a :round or : (better yet) octagonal ground plane, shield the sensitive parts of your :anatomy : with tinfoil, and go for it. : : Jim : : : Jim Weir (A&P/IA, CFI, & other good alphabet soup) : VP Eng RST Pres. Cyberchapter EAA Tech. Counselor : http://www.rst-engr.com : |
#3
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![]() "Rob Turk" wrote in message ... Here's my view of what happened: 1. Someone advises to just put the transponder antenna inside the frame. 2. I place a warning, basically saying there's more to it then just put it in and forget about it. 3. Jim comes back and asks if I have any experience at all that supports my warning, in a somewhat hostile way. 4. I respond that in my experience as ham operator I do have hands-on experience working with this. I caution the group (not Jim..) that diagnosis is harder than hooking up a cheap SWR meter. 5. Jim feels it necessary to dismiss my experience as bullsh*t, posts his entire resume, posts his list of valuable equipment and bashes my spelling. Nowhere did I say Jim was wrong. His 15.000 installed antennas certainly prove it can be done. But that doesn't dismiss that an unknowing home builder might make mistakes. The builder, or a follow-on owner may decide it's fancy to put metallic paint on the plane. Or someone may think it's a good idea to install an inspection hole next to the antenna, and use one of these aluminum covers. Both will influence proper operation of the transponder. I think Jim's response is way out of proportion. I know Jim has plenty of knowledge on the subject and I'm sure he'll agree that you can't just stick the antenna anywhere you want without thinking things through. Therefor I would have expected constructive comments from him, not all-out bashing. Rob The only point Jim made, in his own unique way is, that you are full of ****. He called you on it. Point, game, match. -- Jim in NC |
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