![]() |
If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
|
#1
|
|||
|
|||
![]()
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 |
#2
|
|||
|
|||
![]()
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. |
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
Blue Angels back in Pensacola - practice session - Diamond heading back to the hangar | Pensacola Beachcomber | Aviation Photos | 0 | March 23rd 08 04:28 PM |
Did VHF transceiver need TSO certificate? | [email protected] | Home Built | 13 | March 31st 07 06:27 PM |
FS: Val Com 760 TSO Transceiver | aieo | Aviation Marketplace | 8 | January 25th 07 04:38 PM |
FA: 760ch transceiver | EOC | Aviation Marketplace | 0 | July 27th 05 08:23 PM |
Transceiver | BoDEAN | Products | 0 | April 7th 04 06:08 AM |