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authorkwilson <kwilsonpdx@gmail.com>2011-09-03 21:02:43 (GMT)
committer kwilson <kwilsonpdx@gmail.com>2011-09-03 21:02:43 (GMT)
commit998fd500d784e1c227f90ff8046b7e2c7503858a (patch) (side-by-side diff)
treec8d7753e8097f0b382ecc0f9efec286b5eaec830
parenta60bebb44910297ea52c8ff1a67be23efe64589e (diff)
downloadwiki-998fd500d784e1c227f90ff8046b7e2c7503858a.zip
wiki-998fd500d784e1c227f90ff8046b7e2c7503858a.tar.gz
more markdown foo
Diffstat (more/less context) (ignore whitespace changes)
-rw-r--r--communications.mdwn1
-rw-r--r--cpatuningv4/cpa_tuning.mdwn42
2 files changed, 21 insertions, 22 deletions
diff --git a/communications.mdwn b/communications.mdwn
index 3d5a2e9..3e59ef7 100644
--- a/communications.mdwn
+++ b/communications.mdwn
@@ -17,6 +17,7 @@ Above, ground control to tower [[WiFi]] antennas, circularly polarized patch ant
*Current Antenna Design*
+- [[CPA v4 tuning|cpa_tuning]]
- [[CPA v4 design|CpaDesignv4]]
- [[TrackMaster 3000 - TBC|TrackMaster3000]]
diff --git a/cpatuningv4/cpa_tuning.mdwn b/cpatuningv4/cpa_tuning.mdwn
index fce183d..c7ae5ea 100644
--- a/cpatuningv4/cpa_tuning.mdwn
+++ b/cpatuningv4/cpa_tuning.mdwn
@@ -3,11 +3,11 @@
# CPA v4 Tuning.
-Date: September 2, 2011
-Time: 1300-1700 PDT
-Lab: Portland State University Electromagnetics Lab.
+ - Date: September 2, 2011
+ - Time: 1300-1700 PDT
+ - Lab: Portland State University Electromagnetics Lab.
1900 Sw 4th Avenue, Portland Oregon.
-Investigators: Glenn LeBrasseur, K Wilson, Nathan Bergey
+ - Investigators: Glenn LeBrasseur, K Wilson, Nathan Bergey
## Abstract:
@@ -24,7 +24,7 @@ radiator by (-2.2 mm). The ATV antenna frequency was changed from 2.35 GHz to
## Introduction:
After testing at NW EMC (see [[news/2011-08-12]]) and some experimental work at
-the PSU Electromagnetics Lab (see [[news/2011-08-19.mdwn]) it was decided to
+the PSU Electromagnetics Lab (see [[news/2011-08-19]]) it was decided to
tune the GPS and ATV antennas by modifying the geometry of the antenna radiator
sections. No modifications were performed on the feed network.
@@ -37,30 +37,30 @@ expected results and decide on the magnitude of each incremental modification.
The differential change in antenna frequency is proportional to the differential
change in the vertical dimension (X) of the antenna radiator.
-[[!img cpa4_tune_diagram.png size="500x231" caption="CPA Tuning Diagram"]]
+[[!img cpatunediagram.png size="500x231" caption="CPA Tuning Diagram"]]
By measuring the current dimension of the radiator, and the current frequency
of the antenna an estimate of the necessary adjustment can be made.
- X_d = (f_c/f_g) * X_c
+ Xd = (fc/fg) * Xc
Where:
- - X_d = delta X, the amount to change X (mm)
- - f_c = current frequency (Hz)
- - f_g = goal frequency (Hz)
- - X_c = current value of X (mm)
+ - Xd = delta X, the amount to change X (mm)
+ - fc = current frequency (Hz)
+ - fg = goal frequency (Hz)
+ - Xc = current value of X (mm)
Dimensional measurement was performed with digital calipers.
N.B. Digitial calipers must be calibrated ('zeroed') prior to each measurement.
-Each incremental modification to X_d was on the order of (-1 mm). A 'snap knife'
+Each incremental modification to Xd was on the order of (-1 mm). A 'snap knife'
or thin sharp blade was used against a metal guide held in place around
the cyclinder of the CPA. The metal band and guide are removed during testing
of the antenna. The following photo shows the CPA antennas with the metal band.
In the background is the Network Analyzer with the calibration setup.
From top to bottom the antennas are GPS, ATV and Wifi.
-[[!img CPAwithCal.jpg size="100x100" caption="CPA With Metal Guide Band and Network Analyzer Calibration Setup in Background."]]
+[[!img CPAwithCal.jpg size="100x100" caption="CPA With Metal Guide Band"]]
This photo shows a closeup of the metal band in preparation for a cut.
@@ -80,15 +80,13 @@ copper layer. The two cuts will have a different 'feel' to the operator.
The F4 layer is fibrous and slower to cut while the copper is smooth
and cuts more quickly.
+<div class="image_gallery">
[[!img MakingACut.jpg size="100x100" caption="MakingACut."]]
-
[[!img MakingACut2.jpg size="100x100" caption="MakingACut2."]]
-
[[!img RemovingMaterial.jpg size="100x100" caption="Removing Material."]]
-
[[!img Skive1.jpg size="100x100" caption="Skive."]]
-
[[!img Skive2.jpg size="100x100" caption="Another Skive."]]
+</div>
## GPS CPA Tuning Results
@@ -98,7 +96,7 @@ img1
img2
[[!table data="""
-X_c | X_d | f_c | f_g | Measured Frequency
+Xc | Xd | fc | fg | Measured Frequency
62mm | 1mm | 1.521708GHz | 1.575420GHz | 1.54422GHz
61mm | 1mm | 1.54422GHz | 1.575420GHz | 1.570520GHz
"""]]
@@ -120,17 +118,17 @@ this point.
## ATV CPA Tuning Results
-Calculating the X_d for this antenna resulted in a requirement
-for X_d = (-0.5mm). This is expected to be the minimum manageable
+Calculating the Xd for this antenna resulted in a requirement
+for Xd = (-0.5mm). This is expected to be the minimum manageable
amount of material to skive off the antenna. The actual measured
-amount removed was closer to X_d = (-0.8mm). This is also close
+amount removed was closer to Xd = (-0.8mm). This is also close
to the minimum distance measurement capability of the digital
calipers. The actual amount removed is expected to be between
0.5mm and 0.8mm. It is listed in the table as 0.5mm, which was
the target amount.
[[!table data="""
-X_c | X_d | f_c | f_g | Measured Frequency
+Xc | Xd | fc | fg | Measured Frequency
39.6mm | 0.5mm | 2.35GHz | 2.39GHz | 2.39GHz
"""]]