70cmQuadiDesign - Revision history

NebarnixWikiSysop: Added V3

2015-04-18T19:03:19Z

Added V3

NebarnixWikiSysop at 19:48, 17 April 2015

2015-04-17T19:48:42Z

NebarnixWikiSysop at 19:48, 17 April 2015

2015-04-17T19:48:27Z

NebarnixWikiSysop at 19:47, 17 April 2015

2015-04-17T19:47:01Z

NebarnixWikiSysop at 17:51, 17 April 2015

2015-04-17T17:51:46Z

NebarnixWikiSysop at 17:49, 17 April 2015

2015-04-17T17:49:16Z

NebarnixWikiSysop at 17:46, 17 April 2015

2015-04-17T17:46:39Z

NebarnixWikiSysop: New page: =Note: This page is a reconstruction to a now defuct Univeristy of Idaho nearspace balloon wiki article I posted in 2008= ==70cm Quagi=== Project Status V1 Flight Tested on F08L01 V2 ...

2015-04-17T17:45:56Z

New page: =Note: This page is a reconstruction to a now defuct Univeristy of Idaho nearspace balloon wiki article I posted in 2008= ==70cm Quagi=== Project Status V1 Flight Tested on F08L01 V2 ...

New page

=Note: This page is a reconstruction to a now defuct Univeristy of Idaho nearspace balloon wiki article I posted in 2008=

==70cm Quagi===

Project Status

V1 Flight Tested on F08L01
V2 Preconstruction

==Problem Statement==

Ginger is a bidirectional data routing system equipt with 70cm j-pole antennas. These antennas have a gain of around 2.5dBi and using quarter wave whips the link range is around 37 miles at full power (250kbps) at 10 Watts of output power. To extend the range of operations which might be due to a run away balloon, damaged transmitters, or geographical obstructions, we have built two directional quagi antennas.

The quagi antenna consists of a quad driver (a driven element and a reflector) which already has a higher gain than a dipole fed yagi and reflector. This means that by feeding the same number of directors, a quagi will outperform a yagi at the cost of not being a completely flat design (which is merely a transport concern anyway). The 8 element quagis we have built should have a gain between 12 and 13 dBi and should increase the working distance to 80 miles at 250kbps.

==Photos==

===V1===

===V2===

==Dimensions==

===V1===

The dimensions can be found here, in a 1977 article. http://www.geocities.com/garyntricia/quagi.html

===V2===

The deisgn has been optimized for 437MHz using NEC2. The dimensions are as follows:
RWIRE = .00258826 wire for quads diameter
RROD = .003175 yagi director rod diameter
RE = 0.755962 Total Length of Reflector Element
DE = 0.718693 Total Length of Driven Element
D1 = 0.280124 Total length of Director element
D2 = 0.28434 Total length of Director element
D3 = 0.283594 Total length of Director element
D4 = 0.276571 Total length of Director element
D5 = 0.244994 Total length of Director element
D6 = 0.283213 Total length of Director element
RE2DE = 0.177867 Distance from RE to DE
DE2D1 = 0.138696 Distance from DE to Director
DE2D2 = 0.383653 Distance from DE to Director
DE2D3 = 0.547346 Distance from DE to Director
DE2D4 = 0.851997 Distance from DE to Director
DE2D5 = 0.984569 Distance from DE to Director
DE2D6 = 1.092358 Distance from DE to Director

==Performance==

===V1===
*At 437MHz the SWR is measured at 1.0 for Quagi Orange and 1.2 for Quagi Green (due to coax losses from crappier cable)
*Raw data showing rough measurements of directionality Excel XLS file

===V2===
*At 437MHz the gain should be 13.43 DBi best theoretical gain SWR is 1.07

==Insights==
*Wind is a real problem and keeping both aimed at the same location is not a trivial task. Mount both on a single crossbar and have a lockable central pivot.
*It would be pretty neat to read the GPS data from the CNDH board (already scheduled) and have a QT module to decode them and steer the antennas in the right direction.
*I don't trust ARRL - always simulate those "best anntenna ever" designs first before building!

@@ Line 7: / Line 7: @@
 V1 <span style="color:green">'''Flight Tested on F08L01'''</span><br />
-V2 <span style="color:red">'''Preconstruction'''</span> </span><br />
+V2 <span style="color:red">'''Preconstruction'''</span><br />
 ==Problem Statement==

← Older revision		Revision as of 17:51, 17 April 2015
Line 1:		Line 1:
−	~~'''Bold text'''~~=Note: This page is a reconstruction to a now defuct Univeristy of Idaho nearspace balloon wiki article I posted in 2008=	+	=Note: This page is a reconstruction to a now defuct Univeristy of Idaho nearspace balloon wiki article I posted in 2008=

	==70cm Quagi==		==70cm Quagi==

@@ Line 6: / Line 6: @@
 Project Status
-V1 <span style="color:green">'''Flight Tested on F08L01'''</span><br />
+V1 <span style="color:green">'''Flight Tested on F08L01, two built : status unknown'''</span><br />
-V2 <span style="color:red">'''Preconstruction'''</span><br />
+V2 <span style="color:green">'''One built, no longer in service'''</span><br />
 ==Problem Statement==
@@ Line 13: / Line 15: @@
 The quagi antenna consists of a quad driver (a driven element and a reflector) which already has a higher gain than a dipole fed yagi and reflector. This means that by feeding the same number of directors, a quagi will outperform a yagi at the cost of not being a completely flat design (which is merely a transport concern anyway). The 8 element quagis we have built should have a gain between 12 and 13 dBi and should increase the working distance to 80 miles at 250kbps.
 ==Photos==
@@ Line 20: / Line 24: @@
 ===V2===
 ==Dimensions==
@@ Line 129: / Line 135: @@
   DE2D6 = 1.092358 Distance from DE to Director
 ==Performance==

@@ Line 136: / Line 136: @@
 ===V2===
-*At 437MHz the gain should be 13.43 DBi best theoretical gain SWR is 1.07
+*At 437MHz the gain should be 13.43 DBi best theoretical. SWR S/B 1.07
 ==Insights==

@@ Line 24: / Line 24: @@
 ===V1===
-−
-The dimensions can be found here, in a 1977 article. http://www.geocities.com/garyntricia/quagi.html
+The dimensions, in a 1977 article by K6YNB in QST April 1977
+{|
 ===V2===
-−
 The deisgn has been optimized for 437MHz using NEC2. The dimensions are as follows:
   RWIRE = .00258826 wire for quads diameter

@@ Line 1: / Line 1: @@
-=Note: This page is a reconstruction to a now defuct Univeristy of Idaho nearspace balloon wiki article I posted in 2008=
+'''Bold text'''=Note: This page is a reconstruction to a now defuct Univeristy of Idaho nearspace balloon wiki article I posted in 2008=
 ==70cm Quagi==
@@ Line 6: / Line 6: @@
 Project Status
-V1 Flight Tested on F08L01
+V1 <span style="color:green">'''Flight Tested on F08L01'''</span><br />
-V2 Preconstruction
+V2 <span style="color:red">'''Preconstruction'''</span> </span><br />
 ==Problem Statement==

@@ Line 1: / Line 1: @@
 =Note: This page is a reconstruction to a now defuct Univeristy of Idaho nearspace balloon wiki article I posted in 2008=
-==70cm Quagi===
+==70cm Quagi==
@@ Line 19: / Line 19: @@
 ===V1===
 ===V2===
 ==Dimensions==
@@ Line 77: / Line 52: @@
 ===V1===
- *At 437MHz the SWR is measured at 1.0 for Quagi Orange and 1.2 for Quagi Green (due to coax losses from crappier cable)
+*At 437MHz the SWR is measured at 1.0 for Quagi Orange and 1.2 for Quagi Green (due to coax losses from crappier cable)
- *Raw data showing rough measurements of directionality Excel XLS file
+*Raw data showing rough measurements of directionality Excel XLS file
 ===V2===
- *At 437MHz the gain should be 13.43 DBi best theoretical gain SWR is 1.07
+*At 437MHz the gain should be 13.43 DBi best theoretical gain SWR is 1.07
 ==Insights==
- *Wind is a real problem and keeping both aimed at the same location is not a trivial task. Mount both on a single crossbar and have a lockable central pivot.
+*Wind is a real problem and keeping both aimed at the same location is not a trivial task. Mount both on a single crossbar and have a lockable central pivot.
- *It would be pretty neat to read the GPS data from the CNDH board (already scheduled) and have a QT module to decode them and steer the antennas in the right direction.
+*It would be pretty neat to read the GPS data from the CNDH board (already scheduled) and have a QT module to decode them and steer the antennas in the right direction.
- *I don't trust ARRL - always simulate those "best anntenna ever" designs first before building!
+*I don't trust ARRL - always simulate those "best anntenna ever" designs first before building!