160m Inv L RX was 2 db better then the 6m Dipole from RIP
Monday, April 13, 2020
6m Dipole vs 160m Inv L RX
OK , here it is on RX . RIP's first 3 CQs were RXing the 160m inv v the second 3 was RXing on the 6m dipole.
160m Inv L RX was 2 db better then the 6m Dipole from RIP
160m Inv L RX was 2 db better then the 6m Dipole from RIP
It was polarization
Tested the new 6m Vertical compared to the 160m Inv L that I have been using on 6m and found that the TX to RIP was way lower on the new 1/4 vert then the 160m Inv L.
Conclusion was RIP is Horizontal Polarization and my TX being a 1/4 Vertical was Vertical. I always thought that the 160m Inv L was Vertically polarized ....apparently its more horizontal!
So I through up a quick dipole beside the 160m Inv L . Did 3 transmissions on the Inv L then 3 on the Dipole , results below.
First 3 is RIP RX on the 160m inv L, 9
Second 3 RIP is RX on the new Dipole, 11
So it looks like the dipole is 2 db better then the inv V on TX to RIP
Conclusion was RIP is Horizontal Polarization and my TX being a 1/4 Vertical was Vertical. I always thought that the 160m Inv L was Vertically polarized ....apparently its more horizontal!
So I through up a quick dipole beside the 160m Inv L . Did 3 transmissions on the Inv L then 3 on the Dipole , results below.
First 3 is RIP RX on the 160m inv L, 9
Second 3 RIP is RX on the new Dipole, 11
So it looks like the dipole is 2 db better then the inv V on TX to RIP
Sunday, April 12, 2020
6m antenna test to VE3RIP
Did some FT8 to VE3RIP ( 26 km bearing 308 deg ) ...it LOS to his QTH
3 CQ's and he reported the following levels on each antenna ...
160m Inv L 1/4 Vert Fan Dipole
14 11 4
15 11 4
14 11 4
160ml and 1/4 Vert are Co Located , Fan Dipole is next to the house about 80' lower in elevation then the other two antennas.
RIP was using his Yagi, horizontally polarized. Modeling the 160m Inv L it calls it a horizontally polarized antenna and I am beginning to believe it!
So this is somewhat inconclusive, it could just be the polarization or there could be attenuation in the IFL or it could be the fact that the GP is over 180 deg not 360.
One thing for sure , more work is to be done!
3 CQ's and he reported the following levels on each antenna ...
160m Inv L 1/4 Vert Fan Dipole
14 11 4
15 11 4
14 11 4
160ml and 1/4 Vert are Co Located , Fan Dipole is next to the house about 80' lower in elevation then the other two antennas.
RIP was using his Yagi, horizontally polarized. Modeling the 160m Inv L it calls it a horizontally polarized antenna and I am beginning to believe it!
So this is somewhat inconclusive, it could just be the polarization or there could be attenuation in the IFL or it could be the fact that the GP is over 180 deg not 360.
One thing for sure , more work is to be done!
160m Inv L vs the 6m 1/4
Looks like the 6m 1/4 Vertical may be working well after all. Initial testing had RX down 6-10 db from the new 1/4 Vert as compared to the 160m Inv V. Today I had QSOs with VA3TX in Creemore.
VA3TX QTH is Creemore , bearing 70 deg and 58 km from my QTH.
First QSO was with the 160m Inverted L. I received him at +12 and he reported receiving me at -7.
Second QSO was with the new 1/4 Vertical. I received him at +2 and he reported receiving me at -3.
So its a 10 db drop in RX for a 4 db gain in TX. Need to repeat the test , need some other hams nearby to repeat the test to see if the data is repeatable.
2nd QSO...1/4 Vert
VA3TX QTH is Creemore , bearing 70 deg and 58 km from my QTH.
First QSO was with the 160m Inverted L. I received him at +12 and he reported receiving me at -7.
Second QSO was with the new 1/4 Vertical. I received him at +2 and he reported receiving me at -3.
So its a 10 db drop in RX for a 4 db gain in TX. Need to repeat the test , need some other hams nearby to repeat the test to see if the data is repeatable.
2nd QSO...1/4 Vert
Friday, April 10, 2020
NVIS vs Vertical Round 2
Round 2 of testing , 9am to 10am thsi morning.
DID NOT CHANGE anything , same amtenna , same height and same TX setup.
BLACK DOT - My QTH
RED DOTS - The 80m Vertical
BLUE DOT - The 80m NVIS
GREEN DOTS - Both WSPRs received.
Only the dipole is heard < 200 km
Only the vertical is heard > 350 km with one exception.
Looking at simultaneous transmission reports under
UNDER 300 km
284 km away an the dipole and vertical were about the same.
Between 300 and 400 km
'
Between 300 and 400 km the dipole performed on average performed 3db better the the vertical.
Greater then 400 km
Over 400 km the vertical performed 7 db better then the dipole.
DID NOT CHANGE anything , same amtenna , same height and same TX setup.
BLACK DOT - My QTH
RED DOTS - The 80m Vertical
BLUE DOT - The 80m NVIS
GREEN DOTS - Both WSPRs received.
Only the dipole is heard < 200 km
Only the vertical is heard > 350 km with one exception.
Looking at simultaneous transmission reports under
UNDER 300 km
284 km away an the dipole and vertical were about the same.
Between 300 and 400 km
'
Between 300 and 400 km the dipole performed on average performed 3db better the the vertical.
Greater then 400 km
Over 400 km the vertical performed 7 db better then the dipole.
Tuesday, April 7, 2020
NVIS vs Vertical
Built an 80m Inv V ( apex 30', ends 10' ) aka Near Vertical Incident Skywave Antenna...NVIS.
I also have and love an 80m Vertical aka inverted L ( 30' Vertical , 30 ' Horizontal ) I call this my Vertical antenna.
The idea behind the NVIS is to have better signals in close for " local " use ...say under 500 km.
I have compared both antennas doing simultaneous WSPRs , both day and night. The easiest way at a glance to see the results is the map below...
DAY TEST
Noon to 1pm local - Both stations were transmitting 200 mw or if you prefer +23 dbw +/- 2 db.
BLACK DOT - My QTH
RED DOTS - The 80m Vertical
BLUE DOT - The 80m NVIS
GREEN DOTS - Both WSPRs received.
There are a few variables but its obviously clear that the NVIS is doing what its suppose to do and teh vertical is also performing as expected. Now keep in mind this was done between Noon and 1 pm so the D Layer is full tilt!
Here is the data from stations receiving both the NVIS and Vertical transmissions at the same time.
Click on the image to make it large
NOTE VE3LDP is the NVIS
VA3IMI is the Vertical
DIF is NVIS - Vertical
There is not much difference when you get under 300 km but going out 375 km the signals from the Vertical are 3 to 7 db better ... thats huge!
The closets reception reports was the one and only blue dot 116 km from me and this station only heard the NVIS antenna.
In conclusion the signals in close really were not all that much different then on either antenna. There was a clear advantage for the vertical beyond 300 km.
NIGHT TEST
I was surprised a little but the test was not totally conclusive but close enough.
BLACK DOT - My QTH
RED DOTS - The 80m Vertical
BLUE DOT - The 80m NVIS
GREEN DOTS - Both WSPRs received.
The blue dots through the Midwest are QTHs more or less broadside to the 80 Dipole... makes since as its a 3 db gain in that direction as compared to the vertical.
Here are the simultaneous spots ...
Dipole performed better but make note all the simultaneous spots were from 3 resporters in the US West. The vertical was heard in close < 500 km and then far off > 3000 km. The dipole was more broadside but once you got +/- 45 degrees from SW the vertical was the antenna.
No doubt a little more testing is to be down. There was still pretty good performance off the dipole in spite of it being 30' up at the apex.
NEXT up..lower the APEX and test again.
I also have and love an 80m Vertical aka inverted L ( 30' Vertical , 30 ' Horizontal ) I call this my Vertical antenna.
The idea behind the NVIS is to have better signals in close for " local " use ...say under 500 km.
I have compared both antennas doing simultaneous WSPRs , both day and night. The easiest way at a glance to see the results is the map below...
DAY TEST
Noon to 1pm local - Both stations were transmitting 200 mw or if you prefer +23 dbw +/- 2 db.
BLACK DOT - My QTH
RED DOTS - The 80m Vertical
BLUE DOT - The 80m NVIS
GREEN DOTS - Both WSPRs received.
There are a few variables but its obviously clear that the NVIS is doing what its suppose to do and teh vertical is also performing as expected. Now keep in mind this was done between Noon and 1 pm so the D Layer is full tilt!
Here is the data from stations receiving both the NVIS and Vertical transmissions at the same time.
Click on the image to make it large
NOTE VE3LDP is the NVIS
VA3IMI is the Vertical
DIF is NVIS - Vertical
There is not much difference when you get under 300 km but going out 375 km the signals from the Vertical are 3 to 7 db better ... thats huge!
The closets reception reports was the one and only blue dot 116 km from me and this station only heard the NVIS antenna.
In conclusion the signals in close really were not all that much different then on either antenna. There was a clear advantage for the vertical beyond 300 km.
NIGHT TEST
I was surprised a little but the test was not totally conclusive but close enough.
BLACK DOT - My QTH
RED DOTS - The 80m Vertical
BLUE DOT - The 80m NVIS
GREEN DOTS - Both WSPRs received.
The blue dots through the Midwest are QTHs more or less broadside to the 80 Dipole... makes since as its a 3 db gain in that direction as compared to the vertical.
Here are the simultaneous spots ...
Dipole performed better but make note all the simultaneous spots were from 3 resporters in the US West. The vertical was heard in close < 500 km and then far off > 3000 km. The dipole was more broadside but once you got +/- 45 degrees from SW the vertical was the antenna.
No doubt a little more testing is to be down. There was still pretty good performance off the dipole in spite of it being 30' up at the apex.
NEXT up..lower the APEX and test again.
Monday, April 6, 2020
6m Vert vs 160m Inv L
My 160m inverted L works very good on 6m . Built a 1/4 Very with 8 radials, just like the inverted L and placed it next to the big antenna.
Here is my first FT8 contact ...
Initially I was receiving WXK off the new 1/4 Vert , 3 consecutive transmissions @ -8 db. When he wasn't hearing me I switched to the 160m inv L , he came up 10 db and heard me reporting a -10. His transmissions received on the 160m inv L were 2, 4, 2.
Wow , 10 db difference ...HUGE. The 160m inv L acts more like a long wire on 6m. When its modeled there is a distinct lobe in line with the long horizontal element. The 160m inv L aims S SE ....WXK was 169 deg in AZ. The 160m inv L runs 135 deg ish.
I was expecting better 6m receive on the 160m inv but better transmit. There is one thing that I am slightly suspicious of and thats cable loss. Its 500' to the top of the hill , mostly LDF4 with the last 100' being another chunks of smaller diameter hard line. Swept the cable run a few days ago and the loss was less then 3 db!
Further testing is required before writing this one off. There is a 6m net on Tuesday eve that may provide some answers.
Here is my first FT8 contact ...
Initially I was receiving WXK off the new 1/4 Vert , 3 consecutive transmissions @ -8 db. When he wasn't hearing me I switched to the 160m inv L , he came up 10 db and heard me reporting a -10. His transmissions received on the 160m inv L were 2, 4, 2.
Wow , 10 db difference ...HUGE. The 160m inv L acts more like a long wire on 6m. When its modeled there is a distinct lobe in line with the long horizontal element. The 160m inv L aims S SE ....WXK was 169 deg in AZ. The 160m inv L runs 135 deg ish.
I was expecting better 6m receive on the 160m inv but better transmit. There is one thing that I am slightly suspicious of and thats cable loss. Its 500' to the top of the hill , mostly LDF4 with the last 100' being another chunks of smaller diameter hard line. Swept the cable run a few days ago and the loss was less then 3 db!
Further testing is required before writing this one off. There is a 6m net on Tuesday eve that may provide some answers.
Sunday, April 5, 2020
6m 1/4 Vert with 8 radials...constructed.
Working mids from home , its a NOC job so I am not always super busy. Made a 6m 1/4 Vert with 8 radials while I was monitoring things overnight. Used the dimensions in the previous post.
Here is the antenna before I sealed it all up with silicon.
I have made 160m through 17m antennas just like this and they all have been extremely successful and very inexpensive to make. Being that they are all in a forest having the horizontal elements laying on the ground is a very good thing ...for obvious reasons! I have never had a vertical element taken out by a tree!
With time on my hands I modeled the antenna using MMANA
Here is the antenna with the radials spread evenly...a true isotropic radiator with no gain!
Cut it a little short ...depending on how it tests I may add a bit to the vertical element.
So I played around with the 8 radials moving them all +/- 90 degrees from the X Axis...
Well now , quite the surprise suddenly its a directional antenna with 1.5 db gain over the isotropic as well as a front to back of 2.4 db. Where I live there is very little to the N NE , not going for Europe on 6m. My target is NA so I figured I would aim the antenna S SW it should put a wee bit more signal in the direction of 95% of my 6m activity. Looking at the Smith Chart in the direction of E SE and N NW its about the same as having the radials spread evenly.
On another note if interest.....
This antenna is going at the top of the hill, 500ft of LDF4 figure somewhere around 3 db or a little less attenuation. Also at the top of the hill my 160m inverted L. I have been using this antenna on 6m because it works very well and it even loads without an antenna tuner and around 50.260 its an even match. Its great for sporadic E, LOS up to 350 km regularly and I have even logged a few MSK144 meteor scatter contacts. It will be super interesting to compare the new antenna to the 160m inverted L.
And here is the antenna installed at the top of the hill...I am pleased now to see how it works!
Here is the antenna before I sealed it all up with silicon.
I have made 160m through 17m antennas just like this and they all have been extremely successful and very inexpensive to make. Being that they are all in a forest having the horizontal elements laying on the ground is a very good thing ...for obvious reasons! I have never had a vertical element taken out by a tree!
With time on my hands I modeled the antenna using MMANA
Here is the antenna with the radials spread evenly...a true isotropic radiator with no gain!
Cut it a little short ...depending on how it tests I may add a bit to the vertical element.
So I played around with the 8 radials moving them all +/- 90 degrees from the X Axis...
Well now , quite the surprise suddenly its a directional antenna with 1.5 db gain over the isotropic as well as a front to back of 2.4 db. Where I live there is very little to the N NE , not going for Europe on 6m. My target is NA so I figured I would aim the antenna S SW it should put a wee bit more signal in the direction of 95% of my 6m activity. Looking at the Smith Chart in the direction of E SE and N NW its about the same as having the radials spread evenly.
On another note if interest.....
This antenna is going at the top of the hill, 500ft of LDF4 figure somewhere around 3 db or a little less attenuation. Also at the top of the hill my 160m inverted L. I have been using this antenna on 6m because it works very well and it even loads without an antenna tuner and around 50.260 its an even match. Its great for sporadic E, LOS up to 350 km regularly and I have even logged a few MSK144 meteor scatter contacts. It will be super interesting to compare the new antenna to the 160m inverted L.
And here is the antenna installed at the top of the hill...I am pleased now to see how it works!
Friday, April 3, 2020
6m Antenna Dimensions
Six Meter Wire Antennas
Six Meter CW/SSB
Center Frequency: 50.100 Mhz 147.86 Mhz 3rd Harmonic Halfwave in space is: 9.82 feet 6.68 coax| 8.05 twinlead Quarterwave in space is: 4.91 feet 3.34 coax| 4.03 twinlead Quarterwave Vertical is: 4.67 feet 5.50 foot ground radials Five Eights wave Vertical is: 12.04 feet 4.67 foot ground plane Three Quarter wave Vertical: 14.49 feet 2.34 foot eighthwave Halfwave Dipole/Vertical is: 9.34 feet 4.67 one side. Halfwave Reflector is: 9.81 feet 8.92 for Director Low Mount Halfwave is: 9.14 feet 4.57 one side. Halfwave Folded Dipole is: 9.22 feet 4.61 one side. Halfwave Inverted V is: 9.68 feet 4.84 one side. Colinear Array is: 19.16 feet 9.58 one side. Extended Double Zepp is: 24.07 feet 12.04 one side. Fullwave Quad Loop is: 20.36 feet 5.09 one side. Reflector|Director: 21.38|19.44 5.34| 4.86 one side. Fullwave Delta Loop is: 20.36 feet 6.79 one side. Reflector|Director: 21.38|19.44 7.13| 6.48 one side. Waves 1: 19.16 |1.5: 28.98 |2: 38.80 |2.5: 48.62 |3: 58.44 |4 : 78.08 Waves 5: 97.72 |6.0: 117.37 |7: 137.01 |8.0: 156.65 |9: 176.29 |10: 195.93
Six Meter FM
Center Frequency: 52.525 Mhz 155.01 Mhz 3rd Harmonic Halfwave in space is: 9.37 feet 6.37 coax| 7.68 twinlead Quarterwave in space is: 4.68 feet 3.18 coax| 3.84 twinlead Quarterwave Vertical is: 4.46 feet 5.25 foot ground radials Five Eights wave Vertical is: 11.48 feet 4.46 foot ground plane Three Quarter wave Vertical: 13.82 feet 2.23 foot eighthwave Halfwave Dipole/Vertical is: 8.91 feet 4.46 one side. Halfwave Reflector is: 9.36 feet 8.51 for Director Low Mount Halfwave is: 8.72 feet 4.36 one side. Halfwave Folded Dipole is: 8.80 feet 4.40 one side. Halfwave Inverted V is: 9.23 feet 4.62 one side. Colinear Array is: 18.28 feet 9.14 one side. Extended Double Zepp is: 22.96 feet 11.48 one side. Fullwave Quad Loop is: 19.42 feet 4.85 one side. Reflector|Director: 20.39|18.55 5.10| 4.64 one side. Fullwave Delta Loop is: 19.42 feet 6.47 one side. Reflector|Director: 20.39|18.55 6.80| 6.18 one side. Waves 1: 18.28 |1.5: 27.64 |2: 37.01 |2.5: 46.38 |3: 55.74 |4 : 74.48 Waves 5: 93.21 |6.0: 111.95 |7: 130.68 |8.0: 149.41 |9: 168.15 |10: 186.88Note: At Six meters the diameter of elements in terms of wavelength starts to become large, even with heavy wire like 10 gauge. With tubing elements, an additional shortening factor starts to become important. As elements get fat, the resonant frequency goes down for a given length. This is not a problem on the lower frequencies where even one inch tubing is still small diameter relative to wavelength, but at six meters and above it starts to become more and more significant.
Wednesday, April 1, 2020
80m NVIS Antenna
Built an 80m inverted V and based on VE3RIPs modelling stuck the apex up at 30'. Found some old wire that I pulled down a few tears ago. It was my 80 dipole , down low too! The dimensions were more or less what I was looking for. Put the antenna up just behind the house. To my pleasant surprise it was optimized at 3.750 MHz good for a 1:1 match. I could go +/- 500 kHZ and the VSWR remained below 2:1.
The IFL from the Antenna to the SW was about 60'. I couldn't resist testing the cable for loss before I hung an antenna off it .....
So the loss at 3.2 MHz was 1.7 / 2 = 0.85 db.
The IFL going from the 4X1 SW to the Rack ...
From the rack where the antennas terminate in the house to the 4X1 coaxial sw just up behind the house the loss is 5.1 / 2 = 2.55 db @ 4.8 MHz. So using the NanoVNA the cumulative loss to the 80m Inverted V is somewhere a little over 3 db.
Swept the Antenna from the rack after it was up....
Added a 20' chunks of rg59 and swept again...
The added cable changed the sweet spot slightly.
And the overall return loss @ 1 MHz ( worst VSWR spot )
The return loss came in a 2.28 db so its 2.28 / 2 = 1.15 db of loss. This is quite a bit different then the two cables swept individually which yielded a 3 db loss.
Its probable safe to say the cable loss is somewhere between 1 and 3 db at 3.750 MHz.
The IFL from the Antenna to the SW was about 60'. I couldn't resist testing the cable for loss before I hung an antenna off it .....
So the loss at 3.2 MHz was 1.7 / 2 = 0.85 db.
The IFL going from the 4X1 SW to the Rack ...
From the rack where the antennas terminate in the house to the 4X1 coaxial sw just up behind the house the loss is 5.1 / 2 = 2.55 db @ 4.8 MHz. So using the NanoVNA the cumulative loss to the 80m Inverted V is somewhere a little over 3 db.
Swept the Antenna from the rack after it was up....
Added a 20' chunks of rg59 and swept again...
The added cable changed the sweet spot slightly.
And the overall return loss @ 1 MHz ( worst VSWR spot )
The return loss came in a 2.28 db so its 2.28 / 2 = 1.15 db of loss. This is quite a bit different then the two cables swept individually which yielded a 3 db loss.
Its probable safe to say the cable loss is somewhere between 1 and 3 db at 3.750 MHz.
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