jeepoch
Well-Known Member
- First Name
- Jay
- Joined
- Nov 13, 2019
- Threads
- 1
- Messages
- 952
- Reaction score
- 2,689
- Location
- Longmont, CO
- Vehicle(s)
- 2019 JL Wrangler Sport S 3.6L Auto 2 door, 2.5" lift, 35s
Added all my preliminary communications gear to my JL. I have (thus far):
1. Amateur Radio: Yeasu FT3Dr HT - External Dual-Band VHF / UHF Antenna (call: KF0EUD). Range is potentially worldwide depending on the Repeater and operating mode.
2. CB Radio: Cobra 75 WXST (call: Snowshoe) rarely ever used anymore except on trail. Range is about a mile and a half.
3. Jeep Club Commercial: Radio: Implemented on locked Baofeng UV-5R with UHF Antenna, good several mile range depending on terrain.
4. GMRS Radios: Cobra Micro Talk PR3175 HT (not shown), 10 mile range depending on battery strength.
5. FRS Radios: Cobra Micro Talk FRS-300 HT (not shown), 1 mile range at 500 milliwatts.
6. TBD - Emergency Satellite Guard HT. Still researching...
This plus my cell-phone should keep me connected on trail (or nearly anywhere for that matter).
Spent a small amount of $$ and invested in a MFJ-310 Handheld Antenna Mount Clip for my ham HT. However after purchase, I really despised it's obnoxious placement required for the 2 door. So I came up with this alternative.
While not expecting optimal performance (based purely on antenna theory physics), due to a perceived poor ground-plane, I inverted the window mount and placed it upside-down on the back window hatch (refer to supplied pics). Remarkably though, I can easily hit repeaters 15 to 20 miles away.
Researching into this, it appears that the dual-band antenna is about 1/4 wavelength above the JL chassis. The hardtop being made of fibreglass provides no appreciable attenuation. So it looks like I have a classic vertical dipole mounted 1/4 wavelength (1.5 feet) above a good ground-plane at 144 MHz (2m). 1.7 feet would be ideal.
For UHF at 440 MHz (70 cm) again it's about 1.5 ft above ground plane for 1/2 wavelength where 1.1 ft would be ideal.
So a little less distance than ideal for the VHF 2m Amateur band and a little above ideal distance for the UHF 70cm band vertical dipole antenna mount. Life is always a trade-off set of compromises.
I'm certain I can manipulate the base plate mount and create a more deliberate ground plane by adding a conductive semi-circle plate with about a foot radius. While this will more closely match the 50 ohm feed point impedance of the coaxial feedline, why bother? How good is good enough? I'm not OCD, so the gain of this external antenna is much better than the stock rubber duck.
However, when I get the chance to connect it to an antenna analyzer or SWR meter, I'll have more information. If playing with the base mount provides even more gain, then maybe I'll dink around with it. Still, both VHF and UHF are line-of-sight propagation, hitting repeaters from my Jeep to the Earth's horizon (already) at 5 watts is pretty darn good. This antenna mount required absolutely zero drilling, and provided a very easy cable routing up to the center console. Besides, it looks clean and almost professional. A semi-hemispheric plate while providing better performance (???) would certainly look ugly as sin. I am way more of a geek, so there is that.
Now the cockpit space to mount it required a little finesse. So here I have my ham, CB, Jeep Club and cell-phone mounts. I lost the factory cup wells but found a little portable cup holder contraption I could mount on top of the console instead. A little cheesy but functional. The only real downside is that you can't now open the console with non-sealed beverage containers. Oh well... I'll clean that spill when it happens. In the bigger picture I now have access to about all the frequency spectrum (within a non governmental vehicle) that I could ever require. Certainly much more ready for the Zombie apocalypse.
How cool is that?
Jay
1. Amateur Radio: Yeasu FT3Dr HT - External Dual-Band VHF / UHF Antenna (call: KF0EUD). Range is potentially worldwide depending on the Repeater and operating mode.
2. CB Radio: Cobra 75 WXST (call: Snowshoe) rarely ever used anymore except on trail. Range is about a mile and a half.
3. Jeep Club Commercial: Radio: Implemented on locked Baofeng UV-5R with UHF Antenna, good several mile range depending on terrain.
4. GMRS Radios: Cobra Micro Talk PR3175 HT (not shown), 10 mile range depending on battery strength.
5. FRS Radios: Cobra Micro Talk FRS-300 HT (not shown), 1 mile range at 500 milliwatts.
6. TBD - Emergency Satellite Guard HT. Still researching...
This plus my cell-phone should keep me connected on trail (or nearly anywhere for that matter).
Spent a small amount of $$ and invested in a MFJ-310 Handheld Antenna Mount Clip for my ham HT. However after purchase, I really despised it's obnoxious placement required for the 2 door. So I came up with this alternative.
While not expecting optimal performance (based purely on antenna theory physics), due to a perceived poor ground-plane, I inverted the window mount and placed it upside-down on the back window hatch (refer to supplied pics). Remarkably though, I can easily hit repeaters 15 to 20 miles away.
Researching into this, it appears that the dual-band antenna is about 1/4 wavelength above the JL chassis. The hardtop being made of fibreglass provides no appreciable attenuation. So it looks like I have a classic vertical dipole mounted 1/4 wavelength (1.5 feet) above a good ground-plane at 144 MHz (2m). 1.7 feet would be ideal.
For UHF at 440 MHz (70 cm) again it's about 1.5 ft above ground plane for 1/2 wavelength where 1.1 ft would be ideal.
So a little less distance than ideal for the VHF 2m Amateur band and a little above ideal distance for the UHF 70cm band vertical dipole antenna mount. Life is always a trade-off set of compromises.
I'm certain I can manipulate the base plate mount and create a more deliberate ground plane by adding a conductive semi-circle plate with about a foot radius. While this will more closely match the 50 ohm feed point impedance of the coaxial feedline, why bother? How good is good enough? I'm not OCD, so the gain of this external antenna is much better than the stock rubber duck.
However, when I get the chance to connect it to an antenna analyzer or SWR meter, I'll have more information. If playing with the base mount provides even more gain, then maybe I'll dink around with it. Still, both VHF and UHF are line-of-sight propagation, hitting repeaters from my Jeep to the Earth's horizon (already) at 5 watts is pretty darn good. This antenna mount required absolutely zero drilling, and provided a very easy cable routing up to the center console. Besides, it looks clean and almost professional. A semi-hemispheric plate while providing better performance (???) would certainly look ugly as sin. I am way more of a geek, so there is that.
Now the cockpit space to mount it required a little finesse. So here I have my ham, CB, Jeep Club and cell-phone mounts. I lost the factory cup wells but found a little portable cup holder contraption I could mount on top of the console instead. A little cheesy but functional. The only real downside is that you can't now open the console with non-sealed beverage containers. Oh well... I'll clean that spill when it happens. In the bigger picture I now have access to about all the frequency spectrum (within a non governmental vehicle) that I could ever require. Certainly much more ready for the Zombie apocalypse.
How cool is that?
Jay