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Gain measurement
I am assuming that when the plane is out of range the battery switch opens
and the plane nose dives. Haven't opened the box yet but that is my intention to have the controls work Best regards Art "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 can you know the exact distance the receiver is from the transmitter? 73, Cecil |
On Thu, 12 Aug 2004 19:10:18 GMT, "
wrote: I have looked upward more than 20 times to watch a buzz bomb (V1) go overhead with its characteristic brirp-brurp tone on the assumption that when it ran out of gas it would start its erratic journey to ground. Nope, they were range set against a count down counter that was driven by a patent log mechanism (boats use this everyday as a taffrail log or a screw log). If Churchill had council to your knoweledge as to how theyREALLY were controlled I suspect I would have hit the deck more than once. Proves that ignorance is really bliss. Perhaps so. Too bad Churchill didn't subscribe to the History Channel. ;-) With respect to model airoplanes the controls are limited in power as I understand it and the range consequently is somewhat less tha 200 metres. Since all my antennas are worthless acoording to comment here tests can be undertaken on my own property. Art You would also need some precision receivers for even those worthless antennas. For 10M operating out to 200M, only 20 wavelengths, that is hardly any signal strength change to speak of and to make the plane dive at some pre-determined signal level is going to take quite a sophisticated measurement. Keep in mind that neighboring interstate CB traffic is going to mix in and muddy up the response (your airplane may follow the next Coke truck to Chicago). 73's Richard Clark, KB7QHC |
Well if I have to use suffisticated methods that you describe then this idea
is also worthless as it would not receive your stamp of approval. I'll give the plane to my grandson so that it will not go to waste. Consider post closed Art "Richard Clark" wrote in message ... On Thu, 12 Aug 2004 19:10:18 GMT, " wrote: I have looked upward more than 20 times to watch a buzz bomb (V1) go overhead with its characteristic brirp-brurp tone on the assumption that when it ran out of gas it would start its erratic journey to ground. Nope, they were range set against a count down counter that was driven by a patent log mechanism (boats use this everyday as a taffrail log or a screw log). If Churchill had council to your knoweledge as to how theyREALLY were controlled I suspect I would have hit the deck more than once. Proves that ignorance is really bliss. Perhaps so. Too bad Churchill didn't subscribe to the History Channel. ;-) With respect to model airoplanes the controls are limited in power as I understand it and the range consequently is somewhat less tha 200 metres. Since all my antennas are worthless acoording to comment here tests can be undertaken on my own property. Art You would also need some precision receivers for even those worthless antennas. For 10M operating out to 200M, only 20 wavelengths, that is hardly any signal strength change to speak of and to make the plane dive at some pre-determined signal level is going to take quite a sophisticated measurement. Keep in mind that neighboring interstate CB traffic is going to mix in and muddy up the response (your airplane may follow the next Coke truck to Chicago). 73's Richard Clark, KB7QHC |
Yes, one station emitted dots while another station transmitted dashes, when
receipt of the two signal joined to produce a mono tone the plane was at the predetermined point where it would drop its 'messages' on civilians below" The use of phosper gretly helped following waves even tho fires were outed they then reignighted when the material dried. We only had tar paper windows to ensure that guiding lights were not provided as a help. ArtDave VanHorn" wrote in message ... If you're trying to trip something at a specific point, you might try using a different WWII technique, scaled up. They did bomb releases by flying till they crossed a radio beam. You could use a microwave (10-24 GHz) source as your beam transmitter. Later systems used two beams, and more sophisticated means. Measuring absolute signal strength, at any real distance, is going to have such huge variability as to make it useless. If an anteena has a specific range dominated by its power input and a distance thru air would not a ntenna with more gain allow it to0 travel a longer distance until the plane came to a distance to allow a relay to drop out. I was looking for a meaningfull indication of gain that would not be assaulted gurus negatives with respect to isentropic gain and disbelief of calculations made. What better way for the man in the street to understand antenna gain rather than messing with dbi, dbd e.t.c., which an amateur uses to fulfill his need for conflict? Art |
"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 |
If an anteena has a specific range dominated by its power input and a
distance thru air would not a ntenna with more gain allow it to0 travel a longer distance until the plane came to a distance to allow a relay to drop out. If you were able to place both the transmitter, and the plane in free space, and there weren't other signal sources in the area, this approach might work out. In practice, though, I think you're going to find multipath and reflections to be a real problem. Irregularities in the ground, the presence of buildings and trees, etc. are going to generate enough reflections to cause some serious, and unpredictable changes in the signal strength as seen by the receiver in the plane. De-sensing of the receiver by transmitters on nearby frequencies, noise pickup, directional variations in the plane receiver's antenna, etc. are also going to be problems. I think you'll need a fairly narrow-band receiver, with a well-controlled and fixed gain and a wide dynamic range, and some form of averaging circuitry to get you past the multipath / picket-fence problems. I'm sure that something like this _can_ be done, and can probably be done well enough to result in meaningful measurements. To do so, I think you're going to have to invest a good deal of time, energy, thought, and perhaps money in the design. A poorly-designed approach would introduce so many sources of possible error that any results you got from it would not be particularly meaningful or significant. I was looking for a meaningfull indication of gain that would not be assaulted gurus negatives with respect to isentropic gain and disbelief of calculations made. I'd suggest studying how this sort of measurement is performed in a professional context - e.g. on antenna ranges located out in the country well away from strong RF sources, and in shielded RF-anechoic chambers (for near-field measurements and for higher frequency measurements, where the chamber is a reasonable number of wavelengths across). What better way for the man in the street to understand antenna gain rather than messing with dbi, dbd e.t.c., which an amateur uses to fulfill his need for conflict? Please don't confuse "conflict" with "criticism". The former is unnecessary (although unfortunately it's rather common). The latter is utterly necessary in any form of scientific endeavor! -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
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 |
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! =----- |
"Steve Nosko" wrote in message ... " wrote in message news:YROSc.248059$IQ4.10508@attbi_s02... I am assuming that when the plane is out of range the battery switch opens and the plane nose dives. Haven't opened the box yet but that is my intention to have the controls work Best regards Art YIKES! You haven't flown one yet?? Flying AND doing some kind of signal measurement??? Your idea of a time-travel transponder is a good one. Me thinkth that you will be spending a long time learning to fly and building all the other equipment before you get to do any measurements I don't know what you have, but the regular (the 'good' stuff) R/C equipment has a range exceeding one mile or 1.6 Km. This is much farther than you will be able to see it. Bought it on EBAY fgor $25 shipping included Now camera type transmission to receiver is about 200 feet max so I do not expect to be anywhere in the range that you state. Equipment built ready to go. Keep it in your mind that the engines are driven by batterries and is not the expensive motor type. Big difference. Art There are add-on accessories which will cause something to happen when the transmitter disappears, but without one of these, they can simply continue flying until the motor runs out. it may or may not turn or descend until then depending upon what the controls were doing just before the signal died. 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. Then you have to fly in the far-field, right? ...good luck. I think I'd find a pilot (my son) and fly around with a receiver... -- 73, Steve N, K,9;d, c. i My email has no u's. |
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 |
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 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= |
My luck was good today I got a R/C car at a local garage sale for $10 which
has a 49 megHzs control frequency so I need not be concerned with CB stations. i suspect rerceivers are interchangeable if needs be tho just using an aproach transmitter and measuring activation distances. I am beginning to see this as a viable comparison test that could be used at a club meet Cheers and beers Art " wrote in message news:4QVSc.114239$8_6.109732@attbi_s04... 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. |
Art,
Without the radio signal from the transmitter, the receiver will respond to noise and move the control servos to unpredictable positions, pretty much always resulting in a crash. Modern PCM receivers can be programmed to assume pre-set control positions in the absence of the control signal. This will usually result in a crash. I have hundreds of hours flying RC model aircraft. Russ On Fri, 13 Aug 2004 04:38:51 GMT, " wrote: 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 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= |
Are you aware that we are talking ELECTRIC models
Art "Russ" wrote in message ... Art, Without the radio signal from the transmitter, the receiver will respond to noise and move the control servos to unpredictable positions, pretty much always resulting in a crash. Modern PCM receivers can be programmed to assume pre-set control positions in the absence of the control signal. This will usually result in a crash. I have hundreds of hours flying RC model aircraft. Russ On Fri, 13 Aug 2004 04:38:51 GMT, " wrote: 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 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= |
"Russ" wrote in message ... Art, Without the radio signal from the transmitter, the receiver will respond to noise and move the control servos to unpredictable positions, pretty much always resulting in a crash. Modern PCM receivers can be programmed to assume pre-set control positions in the absence of the control signal. This will usually result in a crash. I have hundreds of hours flying RC model aircraft. Off the wall question: What's the "butt-kickinest" high end radio these days? PCM's been around for many years, anyone doing error correction, FEC, Direct sequence spread spectrum? |
What difference does the motive power have with regard to the control
system? A gassie will react the same way as an electric does when they lose the transmitted control signal, whether by failure or by going out of range. An AM or FM radio will react unpredictably when confronted with loss of signal. PCM radios are more immune to interference and can be pre-set for failure. Or, are you saying that the method of powering the model makes a difference in what happens during radio failure? Even if the model is dynamically stable (most are), if the servos apply full pitch up and full rudder, a spin will ensue. I have built and flown almost every kind of model aircraft, rubber, gas and electric using every kind of contol system including none over the last fifty years. A "back-yard" electric from the bargain store will crash without control. The model can be built light enough so that little, if any, damage will be done. Of course, there is always the chance that the controls will fail in such a position that a glide to landing will occur. In that case, go right out and buy a lotto ticket. Some of those "no control" models used a method using a fuse to burn a rubber band that allowed the empennage to pitch up. The model would stall and (hopefully) return to earth in a steep, deep stall. Little or no damage was sustained because of the lightness of the construction. Russ On Sat, 14 Aug 2004 03:08:46 GMT, " wrote: Are you aware that we are talking ELECTRIC models Art "Russ" wrote in message .. . Art, Without the radio signal from the transmitter, the receiver will respond to noise and move the control servos to unpredictable positions, pretty much always resulting in a crash. Modern PCM receivers can be programmed to assume pre-set control positions in the absence of the control signal. This will usually result in a crash. I have hundreds of hours flying RC model aircraft. Russ On Fri, 13 Aug 2004 04:38:51 GMT, " wrote: 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 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= |
On Fri, 13 Aug 2004 22:19:31 -0500, "Dave VanHorn"
wrote: "Russ" wrote in message .. . Art, Without the radio signal from the transmitter, the receiver will respond to noise and move the control servos to unpredictable positions, pretty much always resulting in a crash. Modern PCM receivers can be programmed to assume pre-set control positions in the absence of the control signal. This will usually result in a crash. I have hundreds of hours flying RC model aircraft. Off the wall question: What's the "butt-kickinest" high end radio these days? PCM's been around for many years, anyone doing error correction, FEC, Direct sequence spread spectrum? Hi Dave, I've been away from it for a couple of years, moving, work and other expensive hobbies. The high-end Airtronics, JRs and Futabas are still the top of the line. They use PCM but no ECC, FEC or SS. The transmitters are pretty programmable though. No need for a seperate heli radio, just program the mixing for a heli control system. The computer allows for memories for different models, each with custom mixing and end-point adjustment. No more sliding servo trays for elevon deltas. Just put a servo on each control surface and mix appropriately. Dual servo ailerons or flaperons, no problem - just set 'em up in the TX. You can spend a grand easy on a radio these days. Funny, I just got a bunch of stuff out of storage last week (new house - YAY!) and was looking at a couple of planes longingly. Russ |
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