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Yes but it still does not have believability on this group as immediately
there would be concern about the accuracy of the equipments used and the suggestion that one must try for accuracy by going into free space as well as the position of your body when obseving measurements. To do thing right one must have complexity to convince a guru Art "Hal Rosser" wrote in message ... How about if you get a field strength meter and walk away from the reference antenna (like a vertical 1/4-wave) until you get a mid-range reading. - then do the same with the tested antenna. compare the distances - and note that signal strength is inversly related to the square of the distance. If the distance for the same reading is double for the beam - that means it has 4 times the effective power in that direction. then convert to db-gain "Art Unwin KB9MZ" wrote in message m... Invariably when antenna gain is mentioned questions arise as to gain measurement and accuracy there of. I do a lot of antenna experiments and declarations of gain never get any where. Ihave now purchased a 27 Mhz electric model airoplane and am now in the process of making a new design antenna and I intend to measure an antennas relative gain my comparing the distance travelled by the model by usind a standard whip antenna and then by using newly designed antenna. I visualise keeping a record of distance travelled of my various experiment antennas. Does any body see any negatives about this aproach which will always be done under zero wind conditions? I am looking for a real world guide to gain to escape from the gain arguments of today. Thanks in advance Art --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.732 / Virus Database: 486 - Release Date: 7/29/2004 |
I thought I had answered this one
As a child I made many balsa wood planes driven by coiled rubber bands. These had a propensity to nose dive into the ground a condition I had expected when the battery relay opened on a present day R/C electric plane I always thought the the one with the most toys wins so the purchased plane can't hurt Regards Artl "Cecil Moore" wrote in message ... Art Unwin KB9MZ wrote: Does any body see any negatives about this aproach which will always be done under zero wind conditions? How do you know the exact distance the receiver is from the transmitter? -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
the one with the most grieving lovers and rich offspring wins
deal with it if we fail to leave the planet we are toast in the mean time there's 2 meter DXCC 73 H. " wrote in message news:%yTSc.246169$%_6.22544@attbi_s01... I thought I had answered this one As a child I made many balsa wood planes driven by coiled rubber bands. These had a propensity to nose dive into the ground a condition I had expected when the battery relay opened on a present day R/C electric plane I always thought the the one with the most toys wins so the purchased plane can't hurt Regards Artl "Cecil Moore" wrote in message ... Art Unwin KB9MZ wrote: Does any body see any negatives about this aproach which will always be done under zero wind conditions? How do you know the exact distance the receiver is from the transmitter? -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
" wrote in message news:PnTSc.246149$%_6.109745@attbi_s01... Jerry, in the Midwest we have a lot of flat lands with corn and soya beens so it is very easy to find a place to test after the harvest. Watched somebody operate one of these and I wopuld expect that you would take an average of say 5 flights each before the battery die. One may see reflections off of a corn cob that has not been gleaned. 27 Mhz was not my frequency of choice but this was available. Planes are two engine type and are controlled by turning the motors on or off for turns..... no flap movements....very simple I would think that doing a distance comparison is more believable when seen than any manufacturers specs and would give me sufficient guidance when an improvement occurs. I certainly think it would add crededance when observed at a club meeting even tho gurus with a little bit of knoweledge will require more sophisticated equipment. If I was comparing one manufacturer to another with respect to R/C controlled equipment it sure would satisfy me as seeing is believing . When I asked for comment I had already put in place all the good things and it was my expectations that the group would focus on the negatives which is how it came out with a balancing list of negatives to compare Appreciate the comments Art "Jerry Martes" wrote in message ... "Art Unwin KB9MZ" wrote in message m... Invariably when antenna gain is mentioned questions arise as to gain measurement and accuracy there of. I do a lot of antenna experiments and declarations of gain never get any where. Ihave now purchased a 27 Mhz electric model airoplane and am now in the process of making a new design antenna and I intend to measure an antennas relative gain my comparing the distance travelled by the model by usind a standard whip antenna and then by using newly designed antenna. I visualise keeping a record of distance travelled of my various experiment antennas. Does any body see any negatives about this aproach which will always be done under zero wind conditions? I am looking for a real world guide to gain to escape from the gain arguments of today. Thanks in advance Art Art If I'd be allowed to change my mind after I got more thought/information on this project, I really like the idea. It will be somewhat of an instrument complex project ?wont it?. A GPS could record alot of data if the plan includes things like that. I would have thought that small variations in distance to the aircraft wouldnt be excessively critical. But, it would be important to keep records of the angle to the aircraft from the antenna. I see Excel and some clocks somewhere in there. This sure would be a fun project. If you do get it working, I'd go to where you are just to see it in action. Jerry Art If the goal is to compare the signal strength of an antenna under test, with the signal strength from a standard antenna, like a quarter wave vertical, I'd think this aircraft method would provide decent information. I do think there is no way to determine the performance of the 'antenna under test' so the antenna design community could accept the data. But, it would be a valid comparison of any antenna with a standard antenna. That would be a "specific antenna gain". How would you sense the variation in signal strength received at the aircraft? Jerry |
ok - he could stand on his head while doing it - would that be complicated
enough ? " wrote in message news:%tTSc.113811$8_6.4732@attbi_s04... Yes but it still does not have believability on this group as immediately there would be concern about the accuracy of the equipments used and the suggestion that one must try for accuracy by going into free space as well as the position of your body when obseving measurements. To do thing right one must have complexity to convince a guru Art "Hal Rosser" wrote in message ... How about if you get a field strength meter and walk away from the reference antenna (like a vertical 1/4-wave) until you get a mid-range reading. - then do the same with the tested antenna. compare the distances - and note that signal strength is inversly related to the square of the distance. If the distance for the same reading is double for the beam - that means it has 4 times the effective power in that direction. then convert to db-gain "Art Unwin KB9MZ" wrote in message m... Invariably when antenna gain is mentioned questions arise as to gain measurement and accuracy there of. I do a lot of antenna experiments and declarations of gain never get any where. Ihave now purchased a 27 Mhz electric model airoplane and am now in the process of making a new design antenna and I intend to measure an antennas relative gain my comparing the distance travelled by the model by usind a standard whip antenna and then by using newly designed antenna. I visualise keeping a record of distance travelled of my various experiment antennas. Does any body see any negatives about this aproach which will always be done under zero wind conditions? I am looking for a real world guide to gain to escape from the gain arguments of today. Thanks in advance Art --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.732 / Virus Database: 486 - Release Date: 7/29/2004 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.732 / Virus Database: 486 - Release Date: 7/29/2004 |
Well I may be in luck as I haven't opened the parcel yet
Maybe a car aproach will satisfy some Art "Fred Hambrecht Sr - Gilbert News" wrote in message ... The correct air craft control freqs are in the 72 Mhz band, 75 is used only for ground vehicles ie. cars, boats etc. As a ham you may use any ham freq IAW amateur regs. "Steve Nosko" wrote in message ... " In the US, 27 MHz is a hazardous frequency to be on...don't know about elsewhere. Good units are in the 75 MHz range. |
Well I opened the parcel to check things out
The frequency is 27.5 MHZ and is to be flown in an area with 200 feet from obstructions such as trees. It will land when beyond range of transmitter Art "Fred Hambrecht Sr - Gilbert News" wrote in message ... The correct air craft control freqs are in the 72 Mhz band, 75 is used only for ground vehicles ie. cars, boats etc. As a ham you may use any ham freq IAW amateur regs. "Steve Nosko" wrote in message ... " In the US, 27 MHz is a hazardous frequency to be on...don't know about elsewhere. Good units are in the 75 MHz range. |
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A Unwin wrote: It will **land** when beyond range of transmitter Let's be precise - it will crash... -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= *** Usenet.com - The #1 Usenet Newsgroup Service on The Planet! *** http://www.usenet.com Unlimited Download - 19 Seperate Servers - 90,000 groups - Uncensored -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= |
wrote:
I thought I had answered this one. Sorry, my other newsgroup account lied and said it didn't post the first time so I switched accounts and asked the question again. 73, Cecil -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Your knoweledge exceeds mine on this subject
The instructions say it can take of and also land on at from hard surfaces. With two engines being in the contol positions of either on or off it would suggest that without power the plane will "glide" to a landing. this gliding after exceeding transmitter range does present distance measurement problems. Perhaps if the plane was weighted the landing could be more "precise" as you say but short of a "crash" Seems like toys holds interests of every one . Art "Silly Penguin" wrote in message ... **** Post for FREE via your newsreader at post.usenet.com **** A Unwin wrote: It will **land** when beyond range of transmitter Let's be precise - it will crash... -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= *** Usenet.com - The #1 Usenet Newsgroup Service on The Planet! *** http://www.usenet.com Unlimited Download - 19 Seperate Servers - 90,000 groups - Uncensored -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= |
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