So, to supplement what has already been said by Admin and Colt, and others...
DSF1960 wrote:- What kind of range is offered?
This is a UHF transceiver. UHF (really anything VHF and up, including UHF) is line-of-sight. This means one thing: If the Earth gets between you and your other transceiver, whether by there being a hill, mountain, or distance so far the horizon gets between you, then you won't "see" each other and you will not be able to converse. **Generally speaking, that is.**
By nature of the frequencies in use, buildings even can pose a problem for signal, but not as much as dirt.
HOWEVER, on the clear, open plains, or on the ocean, if your antenna is six feet off the ground or the water, your horizon is three miles away. Another radio with an antenna the same height would be another three miles from that point on the horizon. Six miles is the total range in that case. As long as there's not a hill or a massive wave between you, you'd be able to talk six miles. Barely.
I have used this phone with a homemade directional antenna as an amateur radio to speak on a repeater whose antenna was nearly 500 feet in the air on a tower. I was over thirty miles away that day. However, it REQUIRED the antenna of the repeater be that high for it to be "line of sight" and at that it would only have just barely been visible over the horizon. Had I been thirty-five miles away, I don't think it would have worked.
DSF1960 wrote:- Is it restricted to communicating with only other BV9500 Pro's?
- Can the user change the walkie talkie frequencies?
It is not restricted (physically) to communicating only with other BV9500 Pros, nor even only with other cellphones, nor even only with Internet connected devices. IT IS A LEGITIMATE TWO-WAY RADIO.
You CAN change the frequencies. It's a thread all in itself, but I delete everything except USA FRS/GMRS then I create a group of my own for local amateur radio stuff, then another group for non-local amateur radio stuff (for when I travel), then maybe a third group for playing around (like listening to other services). I create several channels, each with their own specific frequencies (most with transmit/receive offset so I can use ham repeaters), and if I'm lucky, when I'm done the thing still works.
TAKE NOTE THE LEGALITIES, THOUGH: To transmit on any frequency without a license to do so is illegal (at least here in the United States), though I won't get into the laws because they vary from country to country. Just be mindful if what you're doing is legal or not. Even the FRS stuff here in the United States requires an FCC-type-accepted device, and this device's type acceptance from the FCC is for the cellphone bits, not the two-way radio bits, so even its use on FRS is questionable. (FCC Part 90 or 95, I forget which).
As a licensed amateur radio operator, devices I use for my license privileges fall under FCC Part 97, which is slightly different but still requires certain tolerances be kept (which I'm not sure yet that it does). Fortunately, it's such a low-powered device that I don't expect it to even be a blip on anyone's radar.
DSF1960 wrote:- Can the device be used without the antenna?
Thanks!
As a cellphone, absolutely. As stated by Admin, the antenna is ONLY for the two-way 400-470MHz transceiver.
As a transceiver, in practice it's not advised to use without the antenna. In reality yes, but not very well nor for very long. The reason is that eventually, even at this low power, using it without the antenna will damage the final amplifier which will effectively kill any use as a radio. So, really, no.
Also, just a few things I've noted about this device.
My antenna "broke". Actually, just the rubber outer shell came off. That happens if you sit on it accidentally. Don't sit on it.
Depending on how accurate my measurements were with the outer shell removed (I did it twice and got two results, but they're close), this antenna that it comes with APPEARS to be a half-wave antenna, resonant at somewhere between 400 and 430 MHz (this is a calculation based on dimensions, not a measurement made with electronic equipment). It uses an SMA connector. The phone/radio is MALE, the antenna FEMALE. I purchased an after-market antenna from Amazon, a Nagoya NA-771, intended for Baofeng radios. I had to shave down this "lip" it has, but it works. Arguably. I'm not sure it's any real improvement over the stock antenna. I've also made a four-element yagi and used that, with a piece of RG-58 coax and a BNC-to-SMA adapter, to receive signals from orbiting amateur radio satellites. That's another subject all in itself, too. Of course, the manufacturer might argue that aftermarket antennas are unapproved, but as a licensed ham, I know what I'm doing. If you don't know what you're doing, stick with stock. Actually, it's a decent little antenna for this device. My yagi I made actually has enough gain that it desensitizes the receiver of the phone, such that I had to point the antenna AWAY from the source to get a good signal.
In Amateur Radio, you learn about things like SWR. The stock antenna has a VERY good SWR of about 1.08:1 when I measured it at 434.000 MHz. The Nagoya was considerably worse. These are direct measurements with an SWR meter.
I also have measured the power output, and it appears that low power is somewhere around 0.25 or 0.33 watts (analog meter, 15 W logarithmic scale, hard to read), and high power is about 1.45 watts. These are measurements, not calculations!
Sorry for the book of a post. Imagine if I had to type it on the virtual keyboard of the smartphone!
