HF-1A: FINAL SHORTED MEASUREMENTS 09 APRIL 2015
R.T. loss = 0.696 dB at 5.13 MHz = 0.348 dB one way
Atten 1 (FWD): 2.348 dB; Rser = 13.681; Rsh = 372.18
Atten 2 (REV): 1.652 dB; Rser = 9.567; Rsh = 527.36
Data from running 'farlin4c.exe':
File 5.1M 5.2M R.T. FDTDR delay
HF1A-100.s1p: -4795.991 deg -4886.269 deg 2.5122070313e-6 sec
HF1A-101.s1p: -4796.004 deg -4886.286 deg 2.5122070313e-6 sec
HF1A-102.s1p: -4795.990 deg -4886.273 deg 2.5122070313e-6 sec
------------ ------------- ------------- -------------------
Averages: -4795.995 deg -4886.276 deg 2.5122070313e-6 sec
Result from runnning 'xyl5r13.exe':
"Remove 80.4406 + 8.4294 +/- n * 89.6332 ft"
With appropriate n this is -9.16 inches, very close to previous
results of around -9.5 inches. Thus this cable is already cut too
short by about 9.4 inches, which is sufficient to warrant some
correction by deliberate mismatch of line lengths to input of the
subtractor. More later...
ODD or EVEN:
FDTDR-based electrical length of heliax only is 6.443811 lambda.
Electrical length of relevant periscope section is 0.04702 lambda.
Total electrical length is 6.49083 lambda, which is 12.98 halfwaves.
Therefore conclude that electrical length is an ODD number of
halfwaves for HF-1A.
LOSS-COMPENSATION ATTENUATOR:
R.T. loss = 0.696 dB at 5.13 MHz = 0.348 dB one way (from above)
Atten 1 (FWD): 2.348 dB; Rser = 13.681; Rsh = 372.18
Atten 2 (REV): 1.652 dB; Rser = 9.567; Rsh = 527.36
Check VNA measurement on HF-1A subtractor as built:
A1 - A2 (meas 14 Apr 2015) = 0.7003 dB; misses target by 0.0043 dB
CUT LENGTH ERROR COMPENSATION (COLD):
CUT LENGTH ERROR COMPENSATION (HOT):
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HF-1B: FINAL SHORTED MEASUREMENTS 09 APRIL 2015
R.T. loss = 0.692 dB at 5.13 MHz = 0.346 dB one way
Data from running 'farlin4c.exe':
File 5.1M 5.2M R.T. FDTDR delay
HF1B-100.s1p: -4799.643 deg -4889.990 deg 2.514038086e-6 sec
HF1B-101.s1p: -4799.637 deg -4889.997 deg 2.514038086e-6 sec
HF1B-102.s1p: -4799.651 deg -4889.989 deg 2.514038086e-6 sec
------------ ------------- ------------- -------------------
Averages: -4799.644 deg -4889.992 deg 2.514038086e-6 sec
Result from runnning 'xyl5r13.exe':
"Remove 81.3543 + 8.4294 +/- n * 89.6332 ft"
With appropriate n this is 1.80 inches. Thus this cable is cut
too long by about 1.8 inches, which is marginally sufficient to
warrant some correction by deliberate mismatch of line lengths
to input of the subtractor.
ODD or EVEN:
FDTDR-based electrical length of heliax only is 6.44851 lambda.
Electrical length of relevant periscope section is 0.04702 lambda.
Total electrical length is 6.49553 lambda, which is 12.991 halfwaves.
Therefore conclude that electrical length is an ODD number of
halfwaves for HF-1B.
LOSS-COMPENSATION ATTENUATOR:
R.T. loss = 0.692 dB at 5.13 MHz = 0.346 dB one way (from above)
Atten 1 (FWD): 2.346 dB; Rser = 13.669; Rsh = 372.49
Atten 2 (REV): 1.654 dB; Rser = 9.788; Rsh = 526.73
Check VNA measurement on HF-1B subtractor as built:
A1 - A2 (meas 14 Apr 2015) = 0.7041 dB; misses target by 0.0121 dB
CUT LENGTH ERROR COMPENSATION (COLD):
CUT LENGTH ERROR COMPENSATION (HOT):
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HF-3A: FINAL SHORTED MEASUREMENTS 10 APRIL 2015
R.T. loss = 0.695 dB at 5.13 MHz = 0.343 dB one way
Data from running 'farlin4c.exe':
File 5.1M 5.2M R.T. FDTDR delay
HF3A-100.s1p: -4798.809 deg -4889.458 deg 2.513732910e-6 sec
HF3A-101.s1p: -4798.816 deg -4889.464 deg 2.513732910e-6 sec
HF3A-102.s1p: -4798.823 deg -4889.471 deg 2.513732910e-6 sec
------------ ------------- ------------- -------------------
Averages: -4798.816 deg -4889.464 deg 2.513732910e-6 sec
Result from runnning 'xyl5r13.exe':
"Remove 81.1704 +8.4294 +/- n * 89.6332 ft"
With appropriate n this is -0.40 inches. Thus this cable is cut
too short by a mere 0.4 inches, which is virtually perfect.
ODD or EVEN:
FDTDR-based electrical length of heliax only is 6.44772 lambda.
Electrical length of relevant periscope section is 0.04702 lambda.
Total electrical length is 6.49474 lambda, which is 12.989 halfwaves.
Therefore conclude that electrical length is an ODD number of
halfwaves for HF-3A.
LOSS-COMPENSATION ATTENUATOR:
R.T. loss = 0.695 dB at 5.13 MHz = 0.343 dB one way (from above)
Atten 1 (FWD): 2.343 dB; Rser = 13.652; Rsh = 372.96
Atten 2 (REV): 1.657 dB; Rser = 9.5964; Rsh = 525.78
Check VNA measurement on HF-3A subtractor as built:
A1 - A2 (meas 14 Apr 2015) = 0.6967 dB; misses target by 0.0107 dB
CUT LENGTH ERROR COMPENSATION (COLD):
CUT LENGTH ERROR COMPENSATION (HOT):
---------------------------------------------------------------------------
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HF-3B: FINAL SHORTED MEASUREMENTS 10 APRIL 2015
R.T. loss = 0.757 dB at 5.13 MHz = 0.379 dB one way
Data from running 'farlin4c.exe':
File 5.1M 5.2M R.T. FDTDR delay
HF3B-100.s1p: -5155.803 deg -5253.125 deg 2.708129883e-6 sec
HF3B-101.s1p: -5155.826 deg -5253.144 deg 2.708129883e-6 sec
HF3B-102.s1p: -5155.836 deg -5253.159 deg 2.708129883e-6 sec
------------ ------------- ------------- -------------------
Averages: -5155.822 deg -5253.143 deg 2.708129883e-6 sec
Result from runnning 'xyl5r13.exe':
"Remove 80.9234 +8.4294 +/- n * 89.6332 ft"
With appropriate n this is -3.36 inches. Thus this cable is cut
too short by about 3.4 inches, which is marginally desirous of
correction.
ODD or EVEN:
FDTDR-based electrical length of heliax only is 6.94635 lambda.
Electrical length of relevant periscope section is 0.04702 lambda.
Total electrical length is 6.9934 lambda, which is 13.987 halfwaves.
Therefore conclude that electrical length is an EVEN number of
halfwaves for HF-3B.
LOSS-COMPENSATION ATTENUATOR:
R.T. loss = 0.757 dB at 5.13 MHz = 0.379 dB one way (from above)
Atten 1 (FWD): 2.379 dB; Rser = 13.866; Rsh = 367.39
Atten 2 (REV): 1.621 dB; Rser = 9.3855; Rsh = 537.39
Check VNA measurement on HF-3B subtractor as built:
A1 - A2 (meas 14 Apr 2015) = 0.7434 dB; misses target by 0.0146 dB
CUT LENGTH ERROR COMPENSATION (COLD):
CUT LENGTH ERROR COMPENSATION (HOT):
---------------------------------------------------------------------------
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HF-5A: FINAL SHORTED MEASUREMENTS 10 APRIL 2015
R.T. ret loss = 0.871 dB at 5.13 MHz = 0.436 dB one way
Data from running 'farlin4c.exe':
File 5.1M 5.2M R.T. FDTDR delay
HF5A-100.s1p: -5871.771 deg -5983.396 deg 3.09768677e-6 sec
HF5A-101.s1p: -5871.768 deg -5983.393 deg 3.09768677e-6 sec
HF5A-102.s1p: -5871.776 deg -5983.402 deg 3.09768677e-6 sec
------------ ------------- ------------- -------------------
Averages: -5871.772 deg -5983.397 deg 3.09768677e-6 sec
Result from runnning 'xyl5r13.exe':
"Remove 80.9835 + 8.4294 +/- n * 89.6332 ft"
With appropriate n this is -2.64 inches. Thus this cable is cut
too short by about 2.6 inches, which is probably not worth any
correction.
ODD or EVEN:
FDTDR-based electrical length of heliax only is 7.945566 lambda.
Electrical length of relevant periscope section is 0.04702 lambda.
Total electrical length is 7.9925866 lambda, which is 15.985 halfwaves.
Therefore conclude that electrical length is an EVEN number of
halfwaves for HF-5A.
LOSS-COMPENSATION ATTENUATOR:
R.T. loss = 0.871 dB at 5.13 MHz = 0.436 dB one way (from above)
Atten 1 (FWD): 2.436 dB; Rser = 14.207; Rsh = 358.90
Atten 2 (REV): 1.564 dB; Rser = 9.05; Rsh = 556.86
Check VNA measurement on HF-5A subtractor as built:
A1 - A2 (meas 14 Apr 2015) = 0.7954 dB; misses target by 0.0766 dB
CUT LENGTH ERROR COMPENSATION (COLD):
CUT LENGTH ERROR COMPENSATION (HOT):
---------------------------------------------------------------------------
---------------------------------------------------------------------------
HF-5B: FINAL SHORTED MEASUREMENTS 10 APRIL 2015
R.T. ret loss = 0.859 dB at 5.13 MHz = 0.430 dB one way
Data from running 'farlin4c.exe':
File 5.1M 5.2M R.T. FDTDR delay
HF5B-100.s1p: -5873.028 deg -5984.088 deg 3.09829712e-6 sec
HF5B-101.s1p: -5873.041 deg -5984.094 deg 3.09829712e-6 sec
HF5B-102.s1p: -5873.045 deg -5984.102 deg 3.09829712e-6 sec
------------ ------------- ------------- -------------------
Averages: -5873.038 deg -5984.095 deg 3.09829712e-6 sec
Result from runnning 'xyl5r13.exe':
"Remove 81.2563 + 8.4294 +/- n * 89.6332 ft"
With appropriate n this is +0.63 inches. Thus this cable is cut
too long by about 0.6 inches, which is virtually perfect.
ODD or EVEN:
FDTDR-based electrical length of heliax only is 7.947132 lambda.
Electrical length of relevant periscope section is 0.04702 lambda.
Total electrical length is 7.994152 lambda, which is 15.988 halfwaves.
Therefore conclude that electrical length is an EVEN number of
halfwaves for HF-5B.
LOSS-COMPENSATION ATTENUATOR:
R.T. loss = 0.859 dB at 5.13 MHz = 0.430 dB one way (from above)
Atten 1 (FWD): 2.430 dB; Rser = 14.171; Rsh = 359.77
Atten 2 (REV): 1.570 dB; Rser = 9.08; Rsh = 559.75
Check VNA measurement on HF-5B subtractor as built:
A1 - A2 (meas 14 Apr 2015) = 0.8446 dB; misses target by 0.0154 dB
CUT LENGTH ERROR COMPENSATION (COLD):
CUT LENGTH ERROR COMPENSATION (HOT):
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APPENDIX:
A. LIST OF RELEVANT PC PROGRAMS WRITTEN BY DANA:
> FARLIN4C.EXE:
Used for measuring R.T. (round trip) delay by FD/TDR method.
Also used for absolute R.T. reflection coefficient phase measurements.
Both measurements require either a short or an open at the far end of
the line, and require that the user specify which termination is in
place at measurement time.
Measurement requires the following basic setup parameters in the VNA
used for data collection:
> Start Freq = 0.1 MHz; Stop Freq = 200.1 MHz
> Number of points = 2001
> Sweep: slow enough that > 4 usec R.T. delay does not cause trouble
from the returned swept signal missing the VNA's IF passband.
> Power: not critical, -5 dBm works nicely.
Typical outputs used are R.T. delay to far end, and absolute (unwrapped)
phase values at the bins immediately bracketing the desired operating
frequency. Thus, use values for 5.1 & 5.2 MHz (for 5.13 MHz lines), or
8.1 & 8.2 MHz (for 8.175 MHz lines).
> XYL5R13.EXE (for 5.13 MHz lines) OR XYL8R175.exe (for 8.175 MHz lines)
Used to calculate lengths to be removed to achieve goal of an integer
number of halfwavelengths in the total line between the TX coupler's
midplane and the dipole feedpoint.
Requires manual entry of bracketing phase values from running FARLIN4C
(see above), preferably the average of several runs on separate VNA
measurement data.
Output is a statement of length to cut off the heliax line, +/- n *
a halfwavelength. In effect, a comb of possible cut values, and the
user must then choose the one that best fits the circumstances. This
takes into account the fixed line length in the transmitter between
the TX coupler's mid-plane and the external connection point, as well
as the VF in Heliax.
If one of the comb values is within a few inches of zero, you have
arrived (unless you want to remove another whole halfwavelength of
line for one reason or another).