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#21
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Portable/back up transceiver
"Mike" nospam @ aol.com wrote in message ... I had a Vertex that failed completely after about 5 years. I now have the Icom A4 and I like it just fine. A sample size of 1 tells us little. I have owned 2 Vertex aviation portables over the last decade or so with zero problems. (Yes, a sample size of 2 also tells us little) In my experience (too many years in the 2-way radio biz) Vertex and Icom are the "Honda and Toyota" of that market. You are unlikely to go wrong with either brand.. I wouldn't give you a dime for the difference between the two. Vaughn |
#22
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Portable/back up transceiver
"Mike" nospam @ aol.com wrote in message ... Since all transceivers of this type are limited by the FCC in regards to how much power they can output(and most of them develop the max power allowed at about 1.5w nominal) and since all of them come with essentially identical omnidirectional antennas, I can pretty much assume they will all have very similar ranges, since obviously the transmitter is going to be the limiting factor seeing as how the other end is putting out roughly 7db more power. There are various ways of measuring the output power of an AM transmitter. One manufacturer's 1-watt transmitter may be much the same as another manufacturer's 4-watt transmitter. There are other important issues, such as the type and quality of the modulation and the audio processing. The devil is in the details. Actually, the quality of the receiver is (in general) more important than transmit power. In my experience, both Vertex and Icom are good brand names for that type of equipment. Vaughn |
#23
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Portable/back up transceiver
"Mike" nospam @ aol.com wrote in message ... "RST Engineering - JIm" wrote in message ... Given the fact that a 1 watt transmitter on one end and a 1 microvolt receiver on the other end have a maximum theoretical range of 1800 miles, how in the world can you say that a 4 watt transmitter is "limited by power output"? The limitation is always by line of sight or antenna configuration. Since all transceivers of this type are limited by the FCC in regards to how much power they can output(and most of them develop the max power allowed at about 1.5w nominal) 47CFR87.131 gives the maximum power permitted in the VHF com band as 55 watts carrier. WHere do you get your misinformation? and since all of them come with essentially identical omnidirectional antennas, An omnidirectional (isotropic) antenna is an impossibility, although we do some mathematical "tricks" to reference all antenna gain to isotropic. Gain (dbi - decibels above or below isotropic or dbd - decibels above or below a dipole) by definition are 2.14 dB different, the dipole having gain perpendicular to the elements of 2.14 dbi. Tell me what the form factor is for an antenna putting out a radiation pattern resembling a grapefruit? I can pretty much assume they will all have very similar ranges, since obviously the transmitter is going to be the limiting factor seeing as how the other end is putting out roughly 7db more power. Either you have no idea what you are talking about or it is well into beer-thirty for you. So you can use the opportunity to mentally masturbate your "engineering" knowledge and talk about theoretical true parabolic reflectors Who said anything about parabolic reflectors? I used a plain old ground plane at both ends. 2.14 dbi gain. End one. One watt AM carrier power into a ground plane. End two receiver with one microvolt sensitivity for 10 dB S+N/N being fed by an identical ground plane. If you like, you can replace the ground plane antennas with a plain old straignt dipole with no measurable gain or loss. Actual range at 127 MHz. is 1366.7 statute miles. How the hell do you think we talk to the space shuttle with essentially the same equipment a few MHz. higher with 1 watt handhelds? and receiver sensitivities that don't even approach practical applications Every transceiver on the market today will give you at least half a microvolt for 10 dB S+N/N. I was being generous by saying a full microvolt, which will give you a much better s/n ratio. Haven't designed many VHF radios, have you sonny? , but you're not really contributing much to the OP's question. Perhaps. Perhaps not. But at least I knew what the hell I was talking about. Jim |
#24
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Portable/back up transceiver
"vaughn" wrote in message ... There are various ways of measuring the output power of an AM transmitter. One manufacturer's 1-watt transmitter may be much the same as another manufacturer's 4-watt transmitter. Yes. One trick that a pioneer in the field of solid state avionics design stooped to because in the '60s to get a watt at 127 MHz was a real trick was to measure power "peak to peak". This gives you an inflated number over the standard CW or carrier power of about 3:1. In those days Mark 12s were routinely putting out 10 to 12 watts and solid state "real" watts were about 1.5, which made the "peak to peak" watts somewhere around 4.5 watts, which of course the ad department "rounded up" to 5 watts. There are other important issues, such as the type and quality of the modulation and the audio processing. The devil is in the details. Amen. Decent audio processing in the modulator will make any radio sound good. The problem is that I can count the number of quality VHF AM engineers around today without even taking my pants and shoes off. Not understanding the subtleties of the AM process makes a radio sound thin and whiny, while good processing and modulation makes a real loudenboomer. Actually, the quality of the receiver is (in general) more important than transmit power. That is a question we've been debating for as long as I've been in this game. Sure, I can give you a tenth of a microvolt receiver that crossmods like hell when good buddy fires up his cb a mile away. Or I can do crossmod and intermod like gangbusters and the price you pay is decreased sensitivity. Like the old saw says, price, quality, time. Pick any two. Crossmod, intermod, sensitivity. Pick any two. Jim |
#25
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Portable/back up transceiver
"Peter Dohm" wrote in message
... "Mike" nospam @ aol.com wrote in message ... "RST Engineering - JIm" wrote in message ... Given the fact that a 1 watt transmitter on one end and a 1 microvolt receiver on the other end have a maximum theoretical range of 1800 miles, how in the world can you say that a 4 watt transmitter is "limited by power output"? The limitation is always by line of sight or antenna configuration. Since all transceivers of this type are limited by the FCC in regards to how much power they can output(and most of them develop the max power allowed at about 1.5w nominal) and since all of them come with essentially identical omnidirectional antennas, I can pretty much assume they will all have very similar ranges, since obviously the transmitter is going to be the limiting factor seeing as how the other end is putting out roughly 7db more power. So you can use the opportunity to mentally masturbate your "engineering" knowledge and talk about theoretical true parabolic reflectors and receiver sensitivities that don't even approach practical applications, but you're not really contributing much to the OP's question. I don't always agree with Jim; but he is absolutely right on this one. When I worked as an avionics technicial, most of the problems that I saw were ultimately wiring issues of the coaxial cables (frequently broken at the antenna connector) and only occasionally degraded sensitivity of the receiver. That was long ago, and more modern receivers should suffer far less degradation. The most entertaining case was a Bellanca on which one of the two comm transceivers would successfully receive the tower frequency about 6 miles from the airport and transmit just a little further. It turned out that there was an in-line coax connector which had become disconnected and the radio signals both transmitted and received were only through the braiding of the coax cable! Peter The subjet is "Portable/back up transceiver" |
#26
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Portable/back up transceiver
"RST Engineering - JIm" wrote in message
m... "Mike" nospam @ aol.com wrote in message ... "RST Engineering - JIm" wrote in message ... Given the fact that a 1 watt transmitter on one end and a 1 microvolt receiver on the other end have a maximum theoretical range of 1800 miles, how in the world can you say that a 4 watt transmitter is "limited by power output"? The limitation is always by line of sight or antenna configuration. Since all transceivers of this type are limited by the FCC in regards to how much power they can output(and most of them develop the max power allowed at about 1.5w nominal) 47CFR87.131 gives the maximum power permitted in the VHF com band as 55 watts carrier. WHere do you get your misinformation? Sure, you can transmitt 55 watts. Provided you can find a FCC approved device to do so. Good luck with that. Do you ever wonder why Vertex, Icom, Sporty's, and other handhelds all list their specs as 5w PEP, 1.5w carrier? Do you think they provide such limited power just for sh**s and giggles? and since all of them come with essentially identical omnidirectional antennas, An omnidirectional (isotropic) antenna is an impossibility, although we do some mathematical "tricks" to reference all antenna gain to isotropic. Gain (dbi - decibels above or below isotropic or dbd - decibels above or below a dipole) by definition are 2.14 dB different, the dipole having gain perpendicular to the elements of 2.14 dbi. Tell me what the form factor is for an antenna putting out a radiation pattern resembling a grapefruit? You can skip the bullcrap, Jimmy. All handheld airband transceivers on the market today have essentially identical antennas which are close enough to omnidirectional for this discussion even if it isn't for mental masturbators like yourself. So you can continue to **** on everyone's shoes and try to tell them it's raining if you like, but I've already told you your mental wanking exercise is about as useless to this discussion as man nipples. I can pretty much assume they will all have very similar ranges, since obviously the transmitter is going to be the limiting factor seeing as how the other end is putting out roughly 7db more power. Either you have no idea what you are talking about or it is well into beer-thirty for you. No, I have a very good idea what I'm talking about Jimmy, which is very unfortunate for you since you can't pull your usual trick of trying to baffle everyone with bullcrap. Vertex, Icom, Sporty's and a few other lesser known brands all put out 5w PEP/1.5w carrier according to their specs and all of them have virtually identical antenna designs. The FAA radios put out about 7-9w carrier at the antenna which is pretty close to 7db more power. The FAA receivers are undoubtedly more sensitive than the handheld receivers, but not by 7db, and their squelch is set to around 5 microvolts anyway which is probably going to be pretty close to the handheld. So obviously the most significant range limiting factor is the handheld's transmitter. So you can spew all the crap you want about how I have "no idea", but you haven't offered one iota of anything that is even remotely useful to this discussion and all you're really concerned about is trying to impress yourself with what you think you know. It's the same old grind with you, Jimmy. Nobody on RAP can offer any info on radios because they have "no idea" and you're the only one who does. Then when you're done blowing smoke up everyone's drawers you failed to provide any information that's even remotely useful to the discussion. So you can use the opportunity to mentally masturbate your "engineering" knowledge and talk about theoretical true parabolic reflectors Who said anything about parabolic reflectors? I used a plain old ground plane at both ends. 2.14 dbi gain. End one. One watt AM carrier power into a ground plane. End two receiver with one microvolt sensitivity for 10 dB S+N/N being fed by an identical ground plane. If you like, you can replace the ground plane antennas with a plain old straignt dipole with no measurable gain or loss. Actual range at 127 MHz. is 1366.7 statute miles. How the hell do you think we talk to the space shuttle with essentially the same equipment a few MHz. higher with 1 watt handhelds? I'm pretty sure it's not with a ICOM A14, a Sporty's SP-200, or anything remotely resembling one. So again this begs the question, Jimmy, what value does your mental masturbation exercise bring to the subject line of your post? and receiver sensitivities that don't even approach practical applications Every transceiver on the market today will give you at least half a microvolt for 10 dB S+N/N. I was being generous by saying a full microvolt, which will give you a much better s/n ratio. Haven't designed many VHF radios, have you sonny? , but you're not really contributing much to the OP's question. Perhaps. Perhaps not. But at least I knew what the hell I was talking about. So you managed to impress yourself. Good for you, Jimmy. That's all you're really good for, but I must give you credit. At least you're honest about it. |
#27
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Portable/back up transceiver
"Mike" nospam @ aol.com wrote in message ... Sure, you can transmitt 55 watts. Provided you can find a FCC approved device to do so. Good luck with that. Collins, Sperry, RCA and a few other designed for airline service have a minimum output of 30 watts, achievable last time I looked by either an 829B or a pair of 6146s. That was when I was with the airlines many moons ago. I'm sure that they have improved their designs in 45 years, but I am not sure that even they will go away from devices that can put up with horrendous VSWRs and just get a little hotter. Put your money where your mouth is, bozo, and go buy this sort of gear if you want in the neighborhood of 55 watts. Do you ever wonder why Vertex, Icom, Sporty's, and other handhelds all list their specs as 5w PEP, 1.5w carrier? Do you think they provide such limited power just for sh**s and giggles? Of course not, **** for brains. There are two limitations for handhelds. One is the amount of power you can get from internal batteries, no matter how good the technology. The other is designing to price point and not being able to afford multiwatt solid state devices. Toshiba has a couple of really nice 7 watt ones, but they run about $20 a stick which adds $60-80 to the list price of the radio. That is a marketing disadvantage that they are not willing to take You can skip the bullcrap, Jimmy. All handheld airband transceivers on the market today have essentially identical antennas which are close enough to omnidirectional for this discussion even if it isn't for mental masturbators like yourself. So you can continue to **** on everyone's shoes and try to tell them it's raining if you like, but I've already told you your mental wanking exercise is about as useless to this discussion as man nipples. If you are talking about the rubber resistor that comes with most handhelds, then you apparently don't understand the problem OR the OP does not understand that rubber duckies are fine for about 5 to 10 miles and then are, as you say, breasts on a bull. We did some tests with our S&R unit using three antennas ... the rubber duckie, a home-made collapsible quarter wave whip with a coax connector soldered to it to fit the radio, and an external ground plane antenna fed with ten feet of coax. If you take the ground plane as the standard, the whip was -5 dB and the duckie was -15 dB. Either you have no idea what you are talking about or it is well into beer-thirty for you. No, I have a very good idea what I'm talking about Jimmy, which is very unfortunate for you since you can't pull your usual trick of trying to baffle everyone with bullcrap. Engineering calculations can be bullcrap and it is up to the student to prove otherwise. So far all I've heard is dynamic circumlocution and periphrastic pleonasms. Vertex, Icom, Sporty's and a few other lesser known brands all put out 5w PEP/1.5w carrier according to their specs and all of them have virtually identical antenna designs. As do Microair, XCOM, the older Genaves, Baysides, Dittel, and a few other radios designed to be permanently mounted in an aircraft. The FAA radios put out about 7-9w carrier at the antenna which is pretty close to 7db more power. What the hell is an FAA radio? You do realize that the FAA does NOT have any avenues for approval of radios other than the original equipment list that came with the airplane? I've got a '58 Cessna; the only "approved" radio for that genre of aircraft was the venerable old (vacuum tube) Mark-12. No King, no later Narco, no Genave, no Icom radio was ever "approved" for those aircraft, yet the "wink and nod" method of installation has been used universally for installation of virtually any com radio manufactured. The FAA has taken the tack that if it OK with the FCC, it is OK with them. Which is just fine with all the rest of us. The FAA receivers are undoubtedly more sensitive than the handheld receivers, but not by 7db, and their squelch is set to around 5 microvolts anyway which is probably going to be pretty close to the handheld. Anybody that designs a VHF receiver for anything less than a microvolt is just asking for trouble, but I don't buy 5 microvolts. Even if I did, a 1 watt transmitter produces 5 microvolts with ground planes (or quarter wave whips, or dipoles) at 300 miles, so we are back to the original argument. Transmitter power has damned little to do with it. So obviously the most significant range limiting factor is the handheld's transmitter. That, sir, is patent bull****. Go work the range equation with a noise bandwidth of 25 kHz. and see what YOU come up with. Post it here and we'll argue numbers. Until then you are just blowing smoke up your undies. So you can spew all the crap you want about how I have "no idea", but you haven't offered one iota of anything that is even remotely useful to this discussion and all you're really concerned about is trying to impress yourself with what you think you know. I'm not trying to impress anybody; I'm trying to show facts and figures. So far all I've heard from you is rhetoric. Jim |
#28
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Portable/back up transceiver
RST Engineering - JIm wrote:
"Mike" nospam @ aol.com wrote in message ... Sure, you can transmitt 55 watts. Provided you can find a FCC approved device to do so. Good luck with that. Collins, Sperry, RCA and a few other designed for airline service have a minimum output of 30 watts, achievable last time I looked by either an 829B or a pair of 6146s. That was when I was with the airlines many moons ago. I'm sure that they have improved their designs in 45 years, but I am not sure that even they will go away from devices that can put up with horrendous VSWRs and just get a little hotter. Put your money where your mouth is, bozo, and go buy this sort of gear if you want in the neighborhood of 55 watts. Do you ever wonder why Vertex, Icom, Sporty's, and other handhelds all list their specs as 5w PEP, 1.5w carrier? Do you think they provide such limited power just for sh**s and giggles? Of course not, **** for brains. There are two limitations for handhelds. One is the amount of power you can get from internal batteries, no matter how good the technology. The other is designing to price point and not being able to afford multiwatt solid state devices. Toshiba has a couple of really nice 7 watt ones, but they run about $20 a stick which adds $60-80 to the list price of the radio. That is a marketing disadvantage that they are not willing to take You can skip the bullcrap, Jimmy. All handheld airband transceivers on the market today have essentially identical antennas which are close enough to omnidirectional for this discussion even if it isn't for mental masturbators like yourself. So you can continue to **** on everyone's shoes and try to tell them it's raining if you like, but I've already told you your mental wanking exercise is about as useless to this discussion as man nipples. If you are talking about the rubber resistor that comes with most handhelds, then you apparently don't understand the problem OR the OP does not understand that rubber duckies are fine for about 5 to 10 miles and then are, as you say, breasts on a bull. We did some tests with our S&R unit using three antennas ... the rubber duckie, a home-made collapsible quarter wave whip with a coax connector soldered to it to fit the radio, and an external ground plane antenna fed with ten feet of coax. If you take the ground plane as the standard, the whip was -5 dB and the duckie was -15 dB. Either you have no idea what you are talking about or it is well into beer-thirty for you. No, I have a very good idea what I'm talking about Jimmy, which is very unfortunate for you since you can't pull your usual trick of trying to baffle everyone with bullcrap. Engineering calculations can be bullcrap and it is up to the student to prove otherwise. So far all I've heard is dynamic circumlocution and periphrastic pleonasms. Vertex, Icom, Sporty's and a few other lesser known brands all put out 5w PEP/1.5w carrier according to their specs and all of them have virtually identical antenna designs. As do Microair, XCOM, the older Genaves, Baysides, Dittel, and a few other radios designed to be permanently mounted in an aircraft. The FAA radios put out about 7-9w carrier at the antenna which is pretty close to 7db more power. What the hell is an FAA radio? You do realize that the FAA does NOT have any avenues for approval of radios other than the original equipment list that came with the airplane? I've got a '58 Cessna; the only "approved" radio for that genre of aircraft was the venerable old (vacuum tube) Mark-12. No King, no later Narco, no Genave, no Icom radio was ever "approved" for those aircraft, yet the "wink and nod" method of installation has been used universally for installation of virtually any com radio manufactured. The FAA has taken the tack that if it OK with the FCC, it is OK with them. Which is just fine with all the rest of us. The FAA receivers are undoubtedly more sensitive than the handheld receivers, but not by 7db, and their squelch is set to around 5 microvolts anyway which is probably going to be pretty close to the handheld. Anybody that designs a VHF receiver for anything less than a microvolt is just asking for trouble, but I don't buy 5 microvolts. Even if I did, a 1 watt transmitter produces 5 microvolts with ground planes (or quarter wave whips, or dipoles) at 300 miles, so we are back to the original argument. Transmitter power has damned little to do with it. So obviously the most significant range limiting factor is the handheld's transmitter. That, sir, is patent bull****. Go work the range equation with a noise bandwidth of 25 kHz. and see what YOU come up with. Post it here and we'll argue numbers. Until then you are just blowing smoke up your undies. So you can spew all the crap you want about how I have "no idea", but you haven't offered one iota of anything that is even remotely useful to this discussion and all you're really concerned about is trying to impress yourself with what you think you know. I'm not trying to impress anybody; I'm trying to show facts and figures. So far all I've heard from you is rhetoric. Jim This has been interesting dialog. I know Jim's background from being on the forum for many years. I do not know yours. How about letting the group know. For me, I was educated as an Electrical Engineer, but I have been away from the true engineering for so long, I can just barely read a schematic now. -- Regards, Ross C-172F 180HP Sold KSWI |
#29
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Portable/back up transceiver
Ross wrote:
RST Engineering - JIm wrote: "Mike" nospam @ aol.com wrote in message ... Sure, you can transmitt 55 watts. Provided you can find a FCC approved device to do so. Good luck with that. Collins, Sperry, RCA and a few other designed for airline service have a minimum output of 30 watts, achievable last time I looked by either an 829B or a pair of 6146s. That was when I was with the airlines many moons ago. I'm sure that they have improved their designs in 45 years, but I am not sure that even they will go away from devices that can put up with horrendous VSWRs and just get a little hotter. Put your money where your mouth is, bozo, and go buy this sort of gear if you want in the neighborhood of 55 watts. Do you ever wonder why Vertex, Icom, Sporty's, and other handhelds all list their specs as 5w PEP, 1.5w carrier? Do you think they provide such limited power just for sh**s and giggles? Of course not, **** for brains. There are two limitations for handhelds. One is the amount of power you can get from internal batteries, no matter how good the technology. The other is designing to price point and not being able to afford multiwatt solid state devices. Toshiba has a couple of really nice 7 watt ones, but they run about $20 a stick which adds $60-80 to the list price of the radio. That is a marketing disadvantage that they are not willing to take You can skip the bullcrap, Jimmy. All handheld airband transceivers on the market today have essentially identical antennas which are close enough to omnidirectional for this discussion even if it isn't for mental masturbators like yourself. So you can continue to **** on everyone's shoes and try to tell them it's raining if you like, but I've already told you your mental wanking exercise is about as useless to this discussion as man nipples. If you are talking about the rubber resistor that comes with most handhelds, then you apparently don't understand the problem OR the OP does not understand that rubber duckies are fine for about 5 to 10 miles and then are, as you say, breasts on a bull. We did some tests with our S&R unit using three antennas ... the rubber duckie, a home-made collapsible quarter wave whip with a coax connector soldered to it to fit the radio, and an external ground plane antenna fed with ten feet of coax. If you take the ground plane as the standard, the whip was -5 dB and the duckie was -15 dB. Either you have no idea what you are talking about or it is well into beer-thirty for you. No, I have a very good idea what I'm talking about Jimmy, which is very unfortunate for you since you can't pull your usual trick of trying to baffle everyone with bullcrap. Engineering calculations can be bullcrap and it is up to the student to prove otherwise. So far all I've heard is dynamic circumlocution and periphrastic pleonasms. Vertex, Icom, Sporty's and a few other lesser known brands all put out 5w PEP/1.5w carrier according to their specs and all of them have virtually identical antenna designs. As do Microair, XCOM, the older Genaves, Baysides, Dittel, and a few other radios designed to be permanently mounted in an aircraft. The FAA radios put out about 7-9w carrier at the antenna which is pretty close to 7db more power. What the hell is an FAA radio? You do realize that the FAA does NOT have any avenues for approval of radios other than the original equipment list that came with the airplane? I've got a '58 Cessna; the only "approved" radio for that genre of aircraft was the venerable old (vacuum tube) Mark-12. No King, no later Narco, no Genave, no Icom radio was ever "approved" for those aircraft, yet the "wink and nod" method of installation has been used universally for installation of virtually any com radio manufactured. The FAA has taken the tack that if it OK with the FCC, it is OK with them. Which is just fine with all the rest of us. The FAA receivers are undoubtedly more sensitive than the handheld receivers, but not by 7db, and their squelch is set to around 5 microvolts anyway which is probably going to be pretty close to the handheld. Anybody that designs a VHF receiver for anything less than a microvolt is just asking for trouble, but I don't buy 5 microvolts. Even if I did, a 1 watt transmitter produces 5 microvolts with ground planes (or quarter wave whips, or dipoles) at 300 miles, so we are back to the original argument. Transmitter power has damned little to do with it. So obviously the most significant range limiting factor is the handheld's transmitter. That, sir, is patent bull****. Go work the range equation with a noise bandwidth of 25 kHz. and see what YOU come up with. Post it here and we'll argue numbers. Until then you are just blowing smoke up your undies. So you can spew all the crap you want about how I have "no idea", but you haven't offered one iota of anything that is even remotely useful to this discussion and all you're really concerned about is trying to impress yourself with what you think you know. I'm not trying to impress anybody; I'm trying to show facts and figures. So far all I've heard from you is rhetoric. Jim This has been interesting dialog. I know Jim's background from being on the forum for many years. I do not know yours. How about letting the group know. For me, I was educated as an Electrical Engineer, but I have been away from the true engineering for so long, I can just barely read a schematic now. Jim obviously knows what he is talking about while the other guy is arm waving. As for my background: Got my EE while working as an avionics tech, been an amateur radio operator for 40 years, taught electronics at the college level for a while. -- Jim Pennino Remove .spam.sux to reply. |
#30
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Portable/back up transceiver
"RST Engineering - JIm" wrote in message ... "Mike" nospam @ aol.com wrote in message ... Sure, you can transmitt 55 watts. Provided you can find a FCC approved device to do so. Good luck with that. Collins, Sperry, RCA and a few other designed for airline service have a minimum output of 30 watts, achievable last time I looked by either an 829B or a pair of 6146s. That was when I was with the airlines many moons ago. I'm sure that they have improved their designs in 45 years, but I am not sure that even they will go away from devices that can put up with horrendous VSWRs and just get a little hotter. Put your money where your mouth is, bozo, and go buy this sort of gear if you want in the neighborhood of 55 watts. You do know we're talking about "Portable/back up transceiver(s)", right Jimmy Boy? And I think the OP's intent was ones that are actually made today and not one that was made 40 years ago. Do you ever wonder why Vertex, Icom, Sporty's, and other handhelds all list their specs as 5w PEP, 1.5w carrier? Do you think they provide such limited power just for sh**s and giggles? Of course not, **** for brains. There are two limitations for handhelds. One is the amount of power you can get from internal batteries, no matter how good the technology. The other is designing to price point and not being able to afford multiwatt solid state devices. Toshiba has a couple of really nice 7 watt ones, but they run about $20 a stick which adds $60-80 to the list price of the radio. That is a marketing disadvantage that they are not willing to take I got a really good chuckle out of that one, Jimmy boy. Nice dodge, but I'm really going to have to send the BS flag up on that one. Both Vertex and Icom produce amateur radios that are virtually identical in size to their airband models and some use the exact same batteries. Many models have multiple power settings depending on how much battery life you want, and almost all of them produce more power than their airband models. Oh yeah, I almost forgot to mention that many of them are also at least half the price of the airband models. But you're right, of course. Nobody in their right might would want a handheld airband radio that has signficantly more power because the ones already on the market have a range of "1366.7 statute miles". You crack me up, Jimmy boy. But now I'm sure you'll jump into some spiel about how none of that matters because Marconi himself made a tube type handheld that costs 1/2 the average salary of the average American, or some other great work of irrelevant or fictional nonsense. But that's what I really like about you, Jimmy boy. When someone calls you on your BS, you just come up with even better BS. Brilliant! You can skip the bullcrap, Jimmy. All handheld airband transceivers on the market today have essentially identical antennas which are close enough to omnidirectional for this discussion even if it isn't for mental masturbators like yourself. So you can continue to **** on everyone's shoes and try to tell them it's raining if you like, but I've already told you your mental wanking exercise is about as useless to this discussion as man nipples. If you are talking about the rubber resistor that comes with most handhelds, then you apparently don't understand the problem OR the OP does not understand that rubber duckies are fine for about 5 to 10 miles and then are, as you say, breasts on a bull. We did some tests with our S&R unit using three antennas ... the rubber duckie, a home-made collapsible quarter wave whip with a coax connector soldered to it to fit the radio, and an external ground plane antenna fed with ten feet of coax. If you take the ground plane as the standard, the whip was -5 dB and the duckie was -15 dB. Had you actually bothered to read my first message that you replied to you would have seen that I already mentioned an improved antenna for greater range. So yes, I do understand the "problem". What you can't seem to understand is the topic of conversation (which ironically enough has been in the subject line of all your messages in this thread) are radios you can actually go out and buy at a pilot shop or online, and each and every one of those come with their own antenna. So while someone could "theoretically" hook the output of their handheld to a tube type PA and run the output out of a wire antenna towed behind the aircraft and send voice commands to a mars landing craft, that's just a bit beyond what I consider to be relevant to this discussion. But you go ahead as I can always use the chuckle. Either you have no idea what you are talking about or it is well into beer-thirty for you. No, I have a very good idea what I'm talking about Jimmy, which is very unfortunate for you since you can't pull your usual trick of trying to baffle everyone with bullcrap. Engineering calculations can be bullcrap and it is up to the student to prove otherwise. So far all I've heard is dynamic circumlocution and periphrastic pleonasms. I'm not your "student", Professor, although that one was good for a chuckle. In case you haven't noticed, I'm the one that's schooling you about the perils of being a sexual intellectual. Vertex, Icom, Sporty's and a few other lesser known brands all put out 5w PEP/1.5w carrier according to their specs and all of them have virtually identical antenna designs. As do Microair, XCOM, the older Genaves, Baysides, Dittel, and a few other radios designed to be permanently mounted in an aircraft. You do know we're talking about "Portable/back up transceiver(s)", right Jimmy Boy? If you have any questions, consult the subject line. The FAA radios put out about 7-9w carrier at the antenna which is pretty close to 7db more power. What the hell is an FAA radio? That would be the radio at the other end you're trying to communicate with, Jimmy boy. Come now, let's not make this more complicated than it has to be, OK? I'll break it down for you. When you push the TX button thingy and speak, someone else at the other end is trying to listen. That would be the FAA radio and specifically the receiver. When the FAA pushes their little button thingy and speaks, that would be the FAA transmitter trying to communicate with you through your transceiver. Is this so hard to understand, or do you need a schematic? You do realize that the FAA does NOT have any avenues for approval of radios other than the original equipment list that came with the airplane? I've got a '58 Cessna; the only "approved" radio for that genre of aircraft was the venerable old (vacuum tube) Mark-12. No King, no later Narco, no Genave, no Icom radio was ever "approved" for those aircraft, yet the "wink and nod" method of installation has been used universally for installation of virtually any com radio manufactured. The FAA has taken the tack that if it OK with the FCC, it is OK with them. Which is just fine with all the rest of us. The FAA receivers are undoubtedly more sensitive than the handheld receivers, but not by 7db, and their squelch is set to around 5 microvolts anyway which is probably going to be pretty close to the handheld. Anybody that designs a VHF receiver for anything less than a microvolt is just asking for trouble, but I don't buy 5 microvolts. Even if I did, a 1 watt transmitter produces 5 microvolts with ground planes (or quarter wave whips, or dipoles) at 300 miles, so we are back to the original argument. Transmitter power has damned little to do with it. I don't give a day old dog turd if you buy it or not, Jimmy boy. 5 microvolts is well within the FAA spec and most are set pretty close to that. Controllers don't like radios breaking squelch for no reason because it makes them think someone is trying to call them. So they are set well off the noise floor. And if TX power has "damned little to do with it", why do the FAA transmitters and most airborne radios output pretty close to 10w at the back of the transmitter? I mean, after all, 1w will go "1366.7 statute miles", so it's kind of a head scratcher that the FAA reuses the same enroute frequencies every 600 miles or so, no? Well, at least for you maybe. So obviously the most significant range limiting factor is the handheld's transmitter. That, sir, is patent bull****. Go work the range equation with a noise bandwidth of 25 kHz. and see what YOU come up with. Post it here and we'll argue numbers. Until then you are just blowing smoke up your undies. I'd rather just stay on the practical side of things, Jimmy boy. You're blowing enough smoke as it is and I'm not really in the mood to hear your stories about how NASA is standing outside with a handietalkie communicating with the space shuttle, even as funny as listening to that would be. So you can spew all the crap you want about how I have "no idea", but you haven't offered one iota of anything that is even remotely useful to this discussion and all you're really concerned about is trying to impress yourself with what you think you know. I'm not trying to impress anybody; I'm trying to show facts and figures. So far all I've heard from you is rhetoric. Oh, come one now Jimmy boy. That's just about one step beyond your absurdity I'm prepared to go. Trying to impress yourself is really all I've ever seen you do in this thread or any other, and as funny as this has been, I'm growing tired of reading your attempts and giving you just one more shot at running off a batch of your mental masturbation. It's really quite pathetic. Since you can't even begin to stay on topic despite me giving you multiple opportunities to do so, I won't be replying anymore or even reading your replies, but you go ahead and have the last word and claim victory as I'm sure such things are of great importance to your fragile ego. |
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