Hidden Radio Antenna

Sirus XM, doesn’t get any better. Small disc antenna on roll bar above drivers seat works even with hardtop on.
That is exactly how I used to have my XM antenna mounted. I never had an issue with reception. However my current HU allows the use of Carplay, so I cancelled XM and use Pandora/Spotify. Saves me $$$.
 
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If they worked worth a shit you wouldn't see tall buildings, antenna towers, police cruisers, naval warships, etc. bristling with big-ass antennas.
Once upon a time I worked at an ambulance company. The owner's command vehicle was a Ford F-250 Superduty. He did not want it to look like a mobile porcupine. He had the radio company mount 5 1/4 wave antennas to the frame pointed down. It worked.
 
XM antennas receive their signals from overhead satellites so a rooftop antenna is appropriate. Their signals are also at an EXTREMELY high frequency (2300 MHz) so their tiny antennas are exactly what is required. The higher the frequency the smaller the antenna and visa-versa.
 
Once upon a time I worked at an ambulance company. The owner's command vehicle was a Ford F-250 Superduty. He did not want it to look like a mobile porcupine. He had the radio company mount 5 1/4 wave antennas to the frame pointed down. It worked.
Exactly, quarter-wave at VHF range would be around 30" tall and shorter if they were UHF.
 
There are plenty of modern antenna designs that are very compact and work great. Dielectric resonators and special materials to change the propagation speed and wavelength of the incoming signal are common. Things that were once were very difficult to build to high tolerances and at low cost are now dime a dozen. That's exactly why almost all modern vehicles have great FM radio reception and no whip. You don't need to use a dipole if top of the line costs a few pennies from a modern factory. Considering the raw cost of some metals the smaller antennas can be cheaper even if the technology to produce them is highly specialized. Those modern shark fin antennas don't just have a little whip and loading coil, take one apart and see for yourself.
 
There are plenty of modern antenna designs that are very compact and work great. Dielectric resonators and special materials to change the propagation speed and wavelength of the incoming signal are common.
Dielectric resonator antennas are strictly in the GHz range, they're not usable in the HF, VHF, or UHF bands. Shark fin antennas are physically tiny because they are used for the extremely high frequencies of cellular data, GPS and satellite radio. None of which has anything to do with the HF/VHF (AM/FM) frequencies this thread started over. What is next, radar or submarine ELF antennas?

Why I even got involved in this thread is because some were making inappropriate or at least uneducated buys of antennas. Few people know shit about antennas or even why some antennas can be small but others have to be big or at least bigger. It was meant to be helpful to them.
 
Dielectric resonator antennas are strictly in the GHz range, they're not usable in the HF, VHF, or UHF bands. Shark fin antennas are physically tiny because they are used for the extremely high frequencies of cellular data, GPS and satellite radio. None of which has anything to do with the HF/VHF (AM/FM) frequencies this thread started over. What is next, radar or submarine ELF antennas?

Why I even got involved in this thread is because some were making inappropriate or at least uneducated buys of antennas. Few people know shit about antennas or even why some antennas can be small but others have to be big or at least bigger. It was meant to be helpful to them.

antenna.webp


Whatever you say.
 
If they worked worth a shit you wouldn't see tall buildings, antenna towers, police cruisers, naval warships, etc. bristling with big-ass antennas.
These items all have one thing in common which you forgot about, they transmit. If you read up a bit, you can't use the same tricks to transmit as you can to receive. When they teach you how to service equipment they don't tell you these things, when you build them they are things you have to consider.
 
Just because it has connectors for an AM/FM radio too doesn't mean it works worth a shit at those frequencies, no more than a stubby antenna works well just because it has a plug that fits an AM/FM radio. It's clear you're good at Googling shit but you really don't know enough about the subject to really understand why or why not antennas work well or don't work well at various frequencies. You're now just posting shit that doesn't work well at all the frequencies it has plugs for.
 
Dang, can't find my picture. For all you ham guys out here, somewhere I have a picture of a 21ft tall Commercial Commscope DB224 4 lobe 2m antenna clamped on the back of my EZ-GO golf cart for final testing before we had it installed. It is now our receive antenna sticking 15 ft above the top of a 300ft tower replacing an older one that lighting finally got into our wiring harness on our Pryor, OK 147.06 repeater. That shot might have fit in well with this thread with the caption "Is this too much antenna". Ha Ha
 
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Genuine question: is there a flexible antenna you could run up through the cowl & attach alongside the windshield gasket? Or do you need signal availability all the way around the antenna?
 
Genuine question: is there a flexible antenna you could run up through the cowl & attach alongside the windshield gasket? Or do you need signal availability all the way around the antenna?
The latter. Antennas in direct or very close contact (along the line of the antenna) with metal = poor or no performance.
 
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