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New style astro plane
- Thread starter Cat Driver
- Start date
you're both going blind, the TWO ELEMENTS connecting the loop to the upper bracket ARE EACH 1/4 WAVELENGTH. 1/4 + 1/4 = 1/2.
"and A PAIR OF ONE-QUARTER WAVELENGTH CONDUCTORS extending downwardly from a first reference level (top bracket) to a second reference level. (the loop)"
"and A PAIR OF ONE-QUARTER WAVELENGTH CONDUCTORS extending downwardly from a first reference level (top bracket) to a second reference level. (the loop)"
Its an ANTENNA!SmackDown said:
Only shorted at the bottom, by the loop. The first element is insulated from the main bracket. Draw it out and add it up.W5LZ said:
:lol :lol ...okay, it's an antenna MC but when I look at you guys doing the math my brain goes " D'OH "
how does the mast or "counterpoise" (say what ????) figure into the equation because it's electrically connected and grounded. I figure it will affect swr but has it an affect on anythin' else ?
:lol :lol :lol :lol
how does the mast or "counterpoise" (say what ????) figure into the equation because it's electrically connected and grounded. I figure it will affect swr but has it an affect on anythin' else ?
:lol :lol :lol :lol
"a weird looking 1/4 wave bottom element"
no, it's an open and fully conductive half wave loop*. if you had bothered to read the patent that information* is provided and the evidence of the statement is plainly visible in the design.
no, it's an open and fully conductive half wave loop*. if you had bothered to read the patent that information* is provided and the evidence of the statement is plainly visible in the design.
i do not know enough to have opinions here, i just state what is in the patent sheet.
the patent sheet says two things that interest me here.
1. "the pair of CONDUCTOR MEMBERS are electrically connected at the lower level, and one of the CONDUCTOR MEMBERS is electrically connected at the upper level to the first conductor and to a PROJECTING CONDUCTOR which extends upwardly from that upper level. THE PROJECTING CONDUCTOR HAS AN EFFECTIVE ELECTRICAL LENGTH EQUAL TO THE LENGTH OF THE CONDUCTOR MEMBERS."
(caps used for clarification, not for "yelling")
2. "the electrical circuit of the antenna in fig. 2 is illustrated schematically in fig.5. DIMENSIONS A AND B ARE EACH ONE QUARTER WAVELENGTH IN ELECTRICAL LENGTH"
if you look at the diagram referred to, you can see that A is the top radiator with the horizontal radials.
B is the bottom conductor members, and the hoop.
not one of the concuctor members, not just the hoop, but all three are included as part of "B".
see quote above.
again, i dont have any opinions, or interpretations, i believe that the patent sheet is quite clear about this.
my question to the antenna gurus here is this:
if the antenna IS a half wave antenna, then would the way it is fed make sense for a good match to 50 ohm coax?
loosecannon
the patent sheet says two things that interest me here.
1. "the pair of CONDUCTOR MEMBERS are electrically connected at the lower level, and one of the CONDUCTOR MEMBERS is electrically connected at the upper level to the first conductor and to a PROJECTING CONDUCTOR which extends upwardly from that upper level. THE PROJECTING CONDUCTOR HAS AN EFFECTIVE ELECTRICAL LENGTH EQUAL TO THE LENGTH OF THE CONDUCTOR MEMBERS."
(caps used for clarification, not for "yelling")
2. "the electrical circuit of the antenna in fig. 2 is illustrated schematically in fig.5. DIMENSIONS A AND B ARE EACH ONE QUARTER WAVELENGTH IN ELECTRICAL LENGTH"
if you look at the diagram referred to, you can see that A is the top radiator with the horizontal radials.
B is the bottom conductor members, and the hoop.
not one of the concuctor members, not just the hoop, but all three are included as part of "B".
see quote above.
again, i dont have any opinions, or interpretations, i believe that the patent sheet is quite clear about this.
my question to the antenna gurus here is this:
if the antenna IS a half wave antenna, then would the way it is fed make sense for a good match to 50 ohm coax?
loosecannon
the real question as it pertains to 50 ohms is........
is the half wave fed at the center?
the answer is no.
and it's not a halfwave antenna. elements 16, 18 & 20 constitute an open 1/2 wave loop........you still have a top loaded 1/4 wave above the uppermost bracket that needs to be taken into account here too.
is the half wave fed at the center?
the answer is no.
and it's not a halfwave antenna. elements 16, 18 & 20 constitute an open 1/2 wave loop........you still have a top loaded 1/4 wave above the uppermost bracket that needs to be taken into account here too.
well, the more i read it, the more confused i get.LOL
not so sure the sheet is "clear" anymore.
now, im not saying that it is, but if the bottom section were veiwed as a 1/4 wavelength loop, then the antenna would be fed in the center.
who knows, certainly not me!
are either of the inventors still alive?
lets ask them!
loosecannon
not so sure the sheet is "clear" anymore.
now, im not saying that it is, but if the bottom section were veiwed as a 1/4 wavelength loop, then the antenna would be fed in the center.
who knows, certainly not me!
are either of the inventors still alive?
lets ask them!
loosecannon
2 of Avanti's engineers are still alive. Lou Martino passed away a number of years ago. Herb Blaese is still designing antennas for the commercial industry in the midwest. Howard Van Valzah (WB9IPG) was in charge of the warehouse and sold replacement parts for years, passed on a few years ago also.loosecannon said:
The last conversation I had with Herb found him to be well on in age and not overly excited to talk about CB antennas. Although we spoke for over 45 minutes, it was clear he would rather not be bothered with his old designs. He also asked that I not pass on his contact information.
Engineer #3 who was hired well after the design of the Astroplane is very responsive and builds ham radio antennas. I'll ask him, but he is not one of the designers.