The answer from a theoretical purist is probably, "No," because your diagram specifies zero radiation outside of the disk. Practically speaking, there will always be some radiation above and below the disk and the shape of the disk will not be as perfect as you describe.
A well known solution that approaches your requirements comprises multiple ...
Almost nobody programs Baofeng and similar radios by hand: too difficult, as you discovered. The thing to do is to get your hands on a programming cable and programming software. If you go to a meeting of a ham radio club, there's a good chance that someone will have the cable and the software right there, and will be able to program your radio for you in ...
Achieving such a sharp radiation pattern is difficult. There are many effects that can can cause the radiation pattern of an antenna to be less "sharp". Some of them can be fixed through engineering, such as by manufacturing components to tighter tolerances. Others are unavoidable physical limits. In the best case, diffraction will limit the ...
Some ways, roughly in order of increasing difficulty but also automatability:
Most repeaters have a "courtesy beep" they transmit when their squelch detects the end of an incoming transmission, followed by a period of silence. A direct transmission from a different, normal, transmitter will not have the courtesy beep and silence unless it was deliberately ...
1) listen to FM radio, while scanning 2 meters and 70cm bands at background (as in hiking)?
nope (and only 1 band scanning at a time)
2) set scan hi and low limit, via keypad and/or pc software, so that scan within ham band only (instead full transceiver freq range)?
nope, but you can limit the ranges using chirp
3) scan 2m and 70cm 'simultaneously'. ...
One other setting for each channel that may be giving you problems is Duplex/Simplex. Make certain it is set to Simplex or equivalently "no offset". This feature, when turned on, causes that channel to transmit and receive on different frequencies - typically for using the radio with a repeater.
"MYCALL", "URCALL", "RPT1CALL", and "RPT2CALL" are used to program D-STAR channels in D-STAR-capable radios. Those columns should be left blank for analog FM channels.
MYCALL is your own call sign, eight characters maximum; "/" and suffixes are allowed, as long as everything fits in eight characters.
URCALL is ostensibly for the call sign of the station ...
antenna that have disk like lobes
The pattern of an antenna is never going to be disk-shaped (because the directivity is angle-dependent, not limited to a volume).
But: an omnidirectional antenna (in azimuth) with a very high directive gain in elevation approximates what you want.
A simple vertical stack of vertical half-wavelength dipoles, driven in ...
If you insist on manually programming the radio, this 10-minute YouTube video should help. The programming description begins about 4:20 into the video, but I recommend watching the introductory material because it affects the programming steps.
Note an error in the voice over at 7:46. The author says, "Hit memory one more time," but he actually presses the ...
See Appendix B of the User Manual. BaoFeng calls these "CTCSS" tones, more recently referred to as "PL" tones. Page 67 of the manual describes Menu 13, which allows you to set the value of the sub-audible tone according to table C.2 on page 78.
A lot of the USB programming cables are not supported by the new Windows drivers that are installed automatically -specifically those with the Prolific PL-2303 USB chip set. You 'can' sometimes use them by downloading and installing an older driver. Better to get a proper cable though.
CHIRP Cable Guide
It seems on at least the FTM-400 series, there is a use for this. You can set the scan mode to "all mem" or "select mem":
in "all mem" mode, the radio will scan all of the programmed channels, unless they are set to "skip". In other words, this gets "select" channels plus "off/blank" channels.
in "select mem" mode, which seems to be the default, the radio ...
Some repeaters filter the CTCSS tone. If that's the case, then if you detect one, then it isn't going through the repeater. Some repeaters use a different tone on the output than on the input...also a way to tell.
CB or its close relatives fall into the HF frequency range (covering somewhere around 26 to 28 MHz, depending on country), so anything that accurately calls itself a VHF radio will not transmit (and most likely will not receive) CB.
In general, what you do to answer this kind of question is find the radio's specifications — either on the web site or in the ...
Why would I want an authentic FTDI chip for technical reasons?
With the FTDI-supplied silicon containing several bugs already, my wild guess is that cheap knockoffs are really bug-ridden.
The likelihood that you encounter such a bug when really just using the thing to run a relatively low-speed UART is pretty much 0.
So, as said, FTDI's products' ...
It is highly unlikely that the station transmitting on the output of the repeater will have exactly the same signal strength as the repeater transmitter. Simply monitor the signal strength of the transmission and if it is not typical for the repeater output, the station is likely transmitting on the output.
Yes, it's compatible.
According to baofengradio.us, the compatible models are
UV-5R and UV-5R V2+
BF-F8+ and BF-F9 V2+
UV-82 and UV-82 V2+
BF-888S and the ATR-22
With that information, I have connected the UV-5R and I was able to use the Chirp software with it.
An embedded message allows you to leave a user defined artifact in the memory of the radio that can be recalled by the programming software. This can be used for things such as to identify the specific radio, to identify the source file from which the radio was programmed, to identify the company or individual that programmed that radio, the time and date it ...
I found an answer for this online.
Apparently there's a bug in the firmware of the various BaoFeng handie-talkie models (UV-5R family, BF-F8HP, and others) that causes frequency offset to revert to zero when in channel mode, regardless what was saved in any channel memory.
I found this online document that gives the work around for it:
One must program in ...
There are online instructions and YouTube videos on how to program a BaoFeng radio -- it's the same for all or almost all of their HT models, so if you find instructions for a BF-F8HP, for instance, they'll work for the UV-5R.
The radio, however, doesn't really support half-kilohertz precision in frequency entry from the keypad, so you'd be ahead to spend ...
I have not found any of the Alinco models in CHIRP to work with the DR-635T. In an effort to add it none of the methods used by the other models returned any useful data. I tried contacting Alinco for information but was ignored.
Yes, it'll probably work with CHIRP
Of course, the first place you'd look would be the CHIRP project page. That doesn't list the DR-635, but it does list the DR-135, DR-235 and DR-435, and that might be a good sign (but clearly not a guarantee, since the hardware might simply be different). In fact, CHIRP's alinco driver has a common DR-x35 base class, ...
The Baofeng Tech download page says:
At this time our DMR radios are not compatible with CHIRP; you will need to use the OEM software to update and program your BTECH DMR radios.
Here's a CHIRP "issue" (actually a feature request), which is open and not complete, to add support for the DM-5R. It seems clear, unfortunately, that CHIRP doesn't yet support ...
Another common error is related to their quality control. I had a unit (UV-5R+) that wouldn't work, like that.
Contacted the seller and they sent me a new "body" - and it worked.
So in a case where you are really stuck, I suggest you contact the seller.
Go with the official drivers and software. (I'd recommend that for any radio: that will let you know things are running.)
Some radios (Tytera MD-380, MD-390 and the clone Retevis R3, R8 and Zastone D900) have unlockable boot loaders and reverse-engineered firmware, but the Hytera PD785G is not in that group.
I ended up working with someone from chirp who took an image file from my radio and modified it to work. He said that my radio had been setup with an image for the 220 model radio. This was the second radio he'd done this for in 10 days. I'm not sure how someone would go about making the changes themselves.
In short, the official driver for Windows has been rewritten to block illegitimate copies of the chipset from working. (There are workarounds, which generally involve using older versions of the driver.)
Under Linux, since the driver is open source, it has not been rewritten to block unofficial versions. I can't comment about Mac OS X, since I don't use ...