Hi. I am a technician amateur operator. I was wondering what frequencies better penetrate through buildings? I had heard that vhf-low penetrates through buildings best. Is this true? I live in northern delaware and we have both lots of hills and big buildings. What frequency band would be best for reliable base-to-mobile simplex operations?
What Frequencies penetrate better???
- Thread starter BillQuinn
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rcvmo
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Vhf-low penetrates through buildings best.
There it is!!
But the equipment and infrastructure is size-wise enormous. Duplexers in the lower end around 33 MHz were at least 8ft. tall. Now try sticking that someplace where space is at a minimum.
The best noteable apsect of Low-band is when you get a band opening, all the signals come in and it's hard to decipher who's who talking.
I've found UHF (400-500 MHz) penetetrates probably the best out of all the bands with minimal equipment and infrastructure.
Have fun with the low-bands. I do.
rcvmo
There it is!!
But the equipment and infrastructure is size-wise enormous. Duplexers in the lower end around 33 MHz were at least 8ft. tall. Now try sticking that someplace where space is at a minimum.
The best noteable apsect of Low-band is when you get a band opening, all the signals come in and it's hard to decipher who's who talking.
I've found UHF (400-500 MHz) penetetrates probably the best out of all the bands with minimal equipment and infrastructure.
Have fun with the low-bands. I do.
rcvmo
There's a tradeoff to be had - while lowband will carry farther if all other factors were the same (antenna gain and height, power output, etc) it is much easier to (for example) get a very high-gain mobile antenna for 2M than for 6M - because the antennas are so much bigger at the lower frequencies.
So, as long as you don't have very tall hills and deep valleys, 2M could outperform 6M distance-wise with some good high-gain antennas on each end. (Certainly my experience here.)
On the other hand, 6M will get into the valleys better, so you'd have better fill. You just need to have a decently-large antenna (1/4 wave on 6M is over 4 1/2 feet tall!) to really work well.
There is also a lot more noise on the lower bands, 6M tends to drive me crazy when driving through town as some areas are so noisy there I have to crank the squelch all the way up. Of course, then I can't hear anyone transmitting there either. The higher the band, the quieter they get - in general. PL can help there, if you are using a repeater or only listening for others who will know to use the tone. I'm generally listening to the call channel or SSB.
I like UHF better for shorter-range stuff that needs to penetrate buildings and such. The antennas are also smaller, or just much higher gain for the same size. But it doesn't do well if you need to get long-distance, unless your base station can have a VERY high antenna. (A couple of UHF repeaters here are up around 1100 feet on a TV tower, and they get some wonderful range - still not as good as the VHF ones along side them.) Get behind a hill at any distance away, and the signal will be gone!
So, as long as you don't have very tall hills and deep valleys, 2M could outperform 6M distance-wise with some good high-gain antennas on each end. (Certainly my experience here.)
On the other hand, 6M will get into the valleys better, so you'd have better fill. You just need to have a decently-large antenna (1/4 wave on 6M is over 4 1/2 feet tall!) to really work well.
There is also a lot more noise on the lower bands, 6M tends to drive me crazy when driving through town as some areas are so noisy there I have to crank the squelch all the way up. Of course, then I can't hear anyone transmitting there either. The higher the band, the quieter they get - in general. PL can help there, if you are using a repeater or only listening for others who will know to use the tone. I'm generally listening to the call channel or SSB.
I like UHF better for shorter-range stuff that needs to penetrate buildings and such. The antennas are also smaller, or just much higher gain for the same size. But it doesn't do well if you need to get long-distance, unless your base station can have a VERY high antenna. (A couple of UHF repeaters here are up around 1100 feet on a TV tower, and they get some wonderful range - still not as good as the VHF ones along side them.) Get behind a hill at any distance away, and the signal will be gone!
chrismol1
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by the way, Are there still any frequencies in the lower band that are for recreational use?
I know that there are old walkie talkie and remote control cars on the VHF low band. Is there a maximum power on those freq for remote control or sumtin?
I know that there are old walkie talkie and remote control cars on the VHF low band. Is there a maximum power on those freq for remote control or sumtin?
wa6ube
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Penetrate Better ... that depends ...
My experience with urban areas is that 460 and 800 MHz signals "bounce around" better, and also propagate through narrower openings in structures much better than
VHF-low band or VHF-high band signals ..
Also keep in mind that within a building that has a lot of electronic stuff, there will be a lot higher RF noise floor on VHF low-band and VHF high-band than compared with 460 or 800 MHz..
So .. in general terms .. VHF low-band is great in rural, while VHF-high band is great in
suburban areas. UHF and 800 MHz would propagate better in densely built-up urban areas like major cities ...
Mind you, this comparison is not taking into account wide-area receiver voting networks which will help with talk-in coverage on any band ...
YMMV
BillQuinn said:
My experience with urban areas is that 460 and 800 MHz signals "bounce around" better, and also propagate through narrower openings in structures much better than
VHF-low band or VHF-high band signals ..
Also keep in mind that within a building that has a lot of electronic stuff, there will be a lot higher RF noise floor on VHF low-band and VHF high-band than compared with 460 or 800 MHz..
So .. in general terms .. VHF low-band is great in rural, while VHF-high band is great in
suburban areas. UHF and 800 MHz would propagate better in densely built-up urban areas like major cities ...
Mind you, this comparison is not taking into account wide-area receiver voting networks which will help with talk-in coverage on any band ...
YMMV
wa6ube
Member
Keep in mind:
Antenna performance on VHF-low band hand-held radios "suck" in most instances , so when comparing performance, keep in mind whether the comparison includes hand-held radios or only mobile radios ....
Antenna performance on VHF-low band hand-held radios "suck" in most instances , so when comparing performance, keep in mind whether the comparison includes hand-held radios or only mobile radios ....
rcvmo said:
Bayonne-Bob
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UHF works better at penetrating
VHF works better at distance in rural areas
VHF works better at distance in rural areas
"What frequency band would be best for reliable base-to-mobile simplex operations?"
10M SSB
10M SSB
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It depends on the terrain of the area.
If you were communicating mainly across a city, UHF might work better. VHF is usually the best compromise between penetration, distance and antenna performance.
Lowband is ok in rural areas but as someone has allready mentioned, there's allot of noise around now from electrical devices that makes you turn up the squelch.
If you were communicating mainly across a city, UHF might work better. VHF is usually the best compromise between penetration, distance and antenna performance.
Lowband is ok in rural areas but as someone has allready mentioned, there's allot of noise around now from electrical devices that makes you turn up the squelch.
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