FAQ

We can customize most frequencies. The frequency range for customizations is usually: 136-174/330-400/400-470/470-520MHz and more.

Relay stations can use diplexers, or receive and transmit antennas can be used separately.

The typical frequency range for VHF radios, used primarily for maritime communications and in environments with minimal obstructions, is 136-174MHz. UHF radios, frequently utilized in scenarios such as property management, city communications, and tourism, commonly operate within a 400-470MHz frequency range.

In most contexts, “Duplexer” refers to the capability to separate transmit and receive functions, whereas “Diplexer” denotes the ability to switch among multiple frequency bands.

On Xinlun we have 10 years of experience in specifying models from our wide range of machines for a variety of cleaning tasks. Our dedicated team of technical specialists are always available to give advice on the right equipment for your specific requirement in any environment. Simply go to the Contact Us page and get in touch.

When an amateur station, such as a repeater, is remotely controlled over a radio link, there is another station involved–the station doing the controlling. This “control” station is, under the FCC rules, called an auxiliary station defined by the FCC as “An amateur station, other than a message forwarding system, that is transmitting commu­nications point-to-point within a system of cooperating amateur stations [97.3(a)(7)].” There are a few important rules that apply to auxiliary stations: 1) All amateurs, except Novices, may put auxiliary stations on the air [97.201(a)]. 2) An auxiliary station may transmit only on the 2m and shorter wavelength bands, except the 144.0-144.5 MHz, 145.8-146.0 MHz, 219-220 MHz, 222.00-222.15 MHz, 431-433 MHz, and 435-438 MHz segments. 3) When there is interference, licensees are equally responsible for solving the interference, except where one station is coordinated and the other is not [97.201(c)]. Control links should be coordinated. 4) An auxiliary station may, under certain circumstances, be automatically controlled and may send one-way transmissions [97.201(d), (e)].

A “simplex repeater” is used to extend the range of low power rigs such as handhelds by storing the signal transmitted on a frequency and then retransmitting it through a more powerful or better-situated transmitter on the same frequency. According to the rules, however, such a device is not a repeater since it does not simultaneously retransmit the signals of another station and it does not retransmit the signals on a different channel or channels, as specified in the FCC’s definition of a repeater, so it can’t be operated under automatic control. If a control operator is present and controlling the device, either locally or by remote control, then it can be used. But it cannot be left unattended! On the other hand, it is not limited by the other repeater rules, such as repeater frequencies.

Yes, this is not a problem as long as the Technician is transmitting in his authorized Technician bands. If a Technician transmits through a repeater which also has a part time link to a 10 meter repeater with an output at say, 29.680 MHz, this is not a problem because the repeater station is re-originating the transmission and there must be a control operator with the appropriate 10 meter FM privileges. All that the Technician must be concerned about is his own transmitting frequency, not where his output falls. Of course, a Technician can not transmit directly outside the 28.1-28.5 MHz segment.