With Regards To Portable Devices, Do You Always Use A Single Band Antenna For A Single Band Device Or Do You Ever Use a Dual Band Antenna?

[JASII]

As posted above, say you have a single band portable radio, do you always use a single band antenna or do you ever use a dual band antenna because a dual band antenna might be more useful for other devices in the future?

I have been considering a smartphone that has a built in UHF transceiver. The OEM antenna doesn't look to impressive, so I am wondering, if I do buy it, if I should try and find a single band 70 cm antenna or just buy a dual-band 2 meter/440 Mhz antenna. I am also thinking that for use on a smartphone, I might want to get one of the antennas that is super flexible. Some of the more rigid ones seem like they could, potentially, damage the antenna connector is the antenna itself was bumped into something.

 

[Hit_Factor]

A dual band antenna probably wont perform better and will be longer than needed.

Your other criteria is what you should focus on. Smiley antenna has a wide selection of application specific antennas.

 

[jonwienke]

Multiband antennas don't perform as well as single band antennas, so generally don't go multiband unless you have to.

 

[W5lz]

If multi-band antennas don't perform as well as single band antennas, just how much difference is there? Not -potential- difference, but common everyday, "am I ever going to see/hear that difference?" kind'a stuff. I'm sure there certainly can be a difference, but how much? How significant? Is it specific to a particular situation, or is it a repeatable every time sort of thingy? I honestly feel that most of it is going to be personal preference type stuff. Not always! Just most of the time. I've noticed that if a particular style/model of antenna isn't really doing well, either it, or the manufacturer aren't going to be around in a little while...

 

[nanZor]

Sometimes it depends on the quality of the radio itself over what antenna choice might be better suited.

Example: Say you have a budget transceiver that has somewhat questionable 2nd-harmonic attenuation. While not a total solution, by using a single-band antenna, the 2nd-harmonic won't be radiated as efficiently as if you were using a multi-band antenna that actually worked well on the 2nd-harmonic.

In other words, the last antenna I would use would be a wideband discone mated to a budget transceiver. Yes, the gear should be within specs to begin with, but if not - or just on the hairy edge, try not to radiate as much harmonic junk with a wideband (or multiband) antenna which would do so efficiently.

So nobody is attaching a discone to their portable - in this case, if you run in the 220 band for example, an antenna designed specifically for 220 is what I use, rather than a multiband antenna that is also efficient at 440 mhz.

So it's not a total solution, nor does it replace FCC specs, but at least one is trying to do *something* about it in regards to their neighbors.

 

[WB9YBM]

As posted above, say you have a single band portable radio, do you always use a single band antenna or do you ever use a dual band antenna because a dual band antenna might be more useful for other devices in the future?

I have been considering a smartphone that has a built in UHF transceiver. The OEM antenna doesn't look to impressive, so I am wondering, if I do buy it, if I should try and find a single band 70 cm antenna or just buy a dual-band 2 meter/440 Mhz antenna. I am also thinking that for use on a smartphone, I might want to get one of the antennas that is super flexible. Some of the more rigid ones seem like they could, potentially, damage the antenna connector is the antenna itself was bumped into something.

an antenna engineer I used to work with at Motorola preferred single-band over multi-band antennas because of efficiency issues. What's more important in your application: convenience or efficiency? Also: you didn't mention what kind of connector you've got on your radio; if it were a BNC, that kind of connector is probably the most convenient if you want to swap out easily between different single-band antennas.

 

[AK9R]

Folks, this thread is about single-band antennas vs. dual-band antennas. Let's try to stay on topic.

 

[W5lz]

From another 'direction'... If I have a multiband radio then I'd prefer that the antenna would be usable on those multiple bands. If I'm using a single band radio and don't anticipate ever using a multiband, then I'd use a single band antenna. Lots of variations in that, mainest one as far as I'm concerned is co$t (and where the #^]] do I put it?). If I do happen to change to a multiband radio why can't I just change the antenna too? Sometimes that isn't very practical though. In that case, install another/different antenna? Are you limited to just one antenna?

 

[prcguy]

Assuming the OP is asking about VHF/UHF antennas for portable radios, I don't think any answer can be black or white, there are too many variables. Two single band antennas of the same size from two different mfrs can provide different levels of performance. A single band from one company can be worse than a dual band from another company and so on.

You would have to be very specific and ask if antenna make and model A is better or worse than antenna make and model B to get a meaningful answer.

 

[WB9YBM]

From another 'direction'... If I have a multiband radio then I'd prefer that the antenna would be usable on those multiple bands. If I'm using a single band radio and don't anticipate ever using a multiband, then I'd use a single band antenna. Lots of variations in that, mainest one as far as I'm concerned is co$t (and where the #^]] do I put it?). If I do happen to change to a multiband radio why can't I just change the antenna too? Sometimes that isn't very practical though. In that case, install another/different antenna? Are you limited to just one antenna?

Since I haven't physically checked out the equipment first-hand (so I don't know how practical this is for your application) but I suppose an option might be some kind of antenna splitter device with a single-band antenna at each output--that way you'd get optimum performance without sacrificing performance...

 

[prcguy]

But a particular single band antenna might work worse than a particular dual band antenna. Why go through the hassle of a diplexer until you know the performance of each type of antenna?

Since I haven't physically checked out the equipment first-hand (so I don't know how practical this is for your application) but I suppose an option might be some kind of antenna splitter device with a single-band antenna at each output--that way you'd get optimum performance without sacrificing performance...

 

[W5lz]

... what's wrong with a simple switch? I don't mind something like switching antennas being non-automatic. If that switch is placed half-way reasonably, no big deal. If it's placed outside and around the corner... I'd probably use a remote switching arrangement (done that too). A diplexer? Nope, $orry.

 

[prcguy]

The original question was about single or dual band antenna for a portable radio or smart phone with UHF transceiver. How or why would you use an antenna switch or diplexer on a hand held radio?

... what's wrong with a simple switch? I don't mind something like switching antennas being non-automatic. If that switch is placed half-way reasonably, no big deal. If it's placed outside and around the corner... I'd probably use a remote switching arrangement (done that too). A diplexer? Nope, $orry.

 

[W5lz]

Why? Because you want to or need to for some reason.
How? Put it in-line with antennas. Doesn't matter if it's portable or not.

As for a smartphone... why not a Dick Tracy wrist phone? ... 'nuff said.

 

[WB9YBM]

But a particular single band antenna might work worse than a particular dual band antenna. Why go through the hassle of a diplexer until you know the performance of each type of antenna?

If you want to go that route, why not fund an electronics lab, hire a team of scientists, and do some intense research? Point here is: we can either sit here and analyse this to death, or we can just plug in something to see if a few reasonable assumptions will work. Personally, I've always liked the second approach better--not only because I don't have the finances to hire a research lab, but also because I enjoy the aspect of finding out on my own (I guess you can tell I've worked in research labs myself). The second approach is a lot more fulfilling.

 

[vagrant]

- The OP noted they were considering a smartphone with a UHF transceiver and considering improved antenna options.
- They reaffirmed the premise of using it on a smartphone with the note about the flexibility of the antenna, due to stress concerns on the connector.

Adding a switch or diplexer and using two antennas would be extremely unpractical for the OP and their request. I and others do understand the need for testing but, why would one not consider the practicality that the OP requested?

The best approach would have been for the OP to simply try the OEM antenna. If it fulfilled their needs why bother with a thread? Bother because discussion can be educational and fun until it becomes unreasonable or absurd.

Again, I am reminded how much I enjoy using the ignore feature this forum offers. Thank you RR.