Welcome to troubleshooting. Here we provide answers to the typical questions that may arise when using the UV-1G wireless intercom system. The questions are in no particular order and this section is being constantly updated with information that is helpful to professionals new to the UV-1G system. Click on the “+” sign next to the question for the answer.
If you have a specific question, please don’t hesitate to contact technical support directly (info to the right). Thanks again for supporting Radio Active Designs.
One of your base station transmitters is disabled and the belt pack receiver is looking for a signal. Also, your belt pack receiver or base transmitter may be mistuned.
Radio Active Designs systems are deployed in a variety of Life Safety and Mission Critical applications. For this reason we chose to implement a closed loop system from the belt pack out to the belt pack in. In this manner, if you hear yourself in your own headset, then you can be assured that everyone else on the intercom system heard you as well. This is not the case with digital wireless intercom systems.
Due to the latency of these digital systems, a local side tone is used. This means that you will hear yourself perfectly in your own head set but there is no guarantee that anyone else on the comm system heard you at all. Radio Active Designs uses a “Costas Loop” to ensure that your side tone is a true representation of what everyone else is hearing. The sweeping tone in the belt pack is the receiver looking for the transmitter signal to lock to.
Check the base transmitter “separate” and “combine” switch to ensure that the two transmitters are feeding the ports that you intend to use. If you are going into a TX-8 combiner, then you must place the switch in “separate” and connect both transmitter antennas. If you are using one transmitter antenna, then you must place the switch in “combine”.
When using any transmitter combiner, it is necessary to limit the RF signals going in to each input to one frequency. This is because inserting more than one frequency into a single RF amplifier pallet will create RF intermodulation distortion. The Radio Active Designs UV-1G may be used stand alone or in a multiple system configuration with a transmitter combiner such as the TX-8.
In the stand alone mode of operation, one may place a whip antenna directly on to the rear panel BNC of the unit. In this case, one would place the UV-1G in to “Combined” mode. If you are deploying any transmitter combiner you must place the switch in to the “Separate” mode. This will place the two internal transmitters on to both of the BNC RF output connections on the rear panel.
Make sure that all base stations are in “Master” mode and make all settings. Connect the cable and cycle power on the base stations. If using one to five “slave” base stations, make all setting in the “Master” Mode then change to “Slave”. Again, cycle power on all base stations with the link/sync cables connected.
Using the Sync cable on the rear panel of the Radio Active Designs UV-1G base station opens a world of possibilities. When all of your base stations are synchronized with each other, any belt pack may be tuned across any two transmitter channels regardless of which set of base stations the transmitters are tuned to. In this manner, one may set multiple belt packs on to any set of two RF PL channels.
This is achieved by synchronizing the clock pulse of the Costas Loop mentioned above. When implementing Sync, the top unit in the rack provides the clock signal for all of the base stations below it, or fed to it. This means that all of the other base stations are seeking their internal clock sync from that first unit in the sync chain.
Once all of the sync cables are connected, it is necessary to cycle power on all of the base stations starting with the primary unit. This will establish the clock synchronizer pulse for the rest of the units. The units must be powered up in sequence from top to bottom so that each unit being powered up will sense the clock sync from the unit that is feeding it.
You may be getting AM radiating RF on your wired comm through poorly shielded chassis or cable. Keep all systems powered up and disable the base transmitters. Get some distance between the base transmitter antenna and the wired comm cables and chassis. Also, use only the amount of RF power out of the base as is required for the task at hand. You rarely need to use 250 milliWatts.
Radio Active Designs implements Amplitude Modulation rather than traditional Frequency Modulation. This is because our goal from the start was Spectral Efficiency. Due to the fact that we are using AM, we can pack 200 belt packs and 30 base stations in the same UHF footprint as One 4 drop FM system. That makes us 30 times more spectrally efficient.
Amplitude Modulation has the ability to be demodulated inside of poorly shielded electronics equipment. In fact, all that is required to demodulate an AM signal is an active electronics circuit; even one that is not related to RF in the least. In addition, our RAD UV-1G uses direct conversion meaning that there is no Intermediate Frequency. The RF signal IS the audio signal. This is why you hear some form of the audio being transmitted on the base station.
The headset cable is the counterpoise for the VHF transmitter antenna. It must be connected for proper transmission from the belt pack.
Radio Active Designs belt packs transmit in the VHF band from 174-216 MHz which is TV channel 7 through 13. If we used an external antenna for the belt pack, it would be 16 inches long! Probably wouldn’t go over too well nowadays.
That is why we designed an internal meander antenna for transmission from the belt pack. We use the head set cable as the counterpoise for the transmit antenna thus the head set must be connected for maximum transmission.
The belt pack locks to Channel 1 to ensure a closed loop system. Channel 1 must be turned on in the belt pack receiver. If you do not want to hear it, turn the volume control down.
Radio Active Designs wireless intercom systems are used in mission critical operations from Nuclear power plants to Space vehicle launch communications. We deploy a Costas Loop closed locked loop system for the side tone. The Costas Loop signal is transmitted on channel 1 of the base station. It is necessary to tune your belt pack to channel 1 to assure proper lock.
- Check for proper placement of RX antenna in comparison to TX antenna.
- Check your operating frequencies.
- Check your RF 50ohm Low Loss cables.
Details: There are three things you need to check.
- Check your placement of your base station RX antenna and make sure it is not in front of a TX antenna or pointed directly and positioned too close to a video wall or another piece of equipment that puts out high RF noise. RX antennas should be placed high, behind and to the side of a TX antenna and away from items such as Power Distribution, lighting dimmers and video walls. TX antennas should be placed high as well.
- Check your TX and RX frequencies of your base station to make sure they are not being stepped on by other frequencies or tuned in a high noise floor environment. If the frequency is clean, but there is a higher than normal noise floor, you can attenuate the RX sensitivity at the base station to help lower the noise floor. The pack will TX out more effectively to the base station. You can do this individually or globally.
- Check your 50ohm Low Loss RF cables for a short in the connector (shield touching the core) or possibly a broken pin in the connector. Cables get damaged if not taken care of.
It is not recommended unless you power up in TX Off mode.
Details: It is not a good idea to power up the base station without antennas connected because the TX amplifier is looking for a load when it is powered up. An amplifier with no load will cause strain on the amp and shorten it’s life or cause it to fail.
An alternative is to power up the Base Station in TX off mode. Hold the TALK button on the right while turning on the Base Station. Let go of the TALK button until you see ”TX OFF” in the LCD screen. Another benefit of doing this is that your base station won’t interfere with any other frequencies at your location if your base station is not already programmed. You can turn the TX in the base station back on manually or by using the software to program it.
No, your batteries will not drain if left in a unpowered battery charger. Always top off a battery before an event if left unused in or out of the battery charger for longer than a day.
Make sure all of your base station RX inputs are connected to an antenna via a VF-8 or DB-VIC RX multi-coupler.
RAD recommends the user to wear a two-way radio on the OPPOSITE side of the RAD pack to avoid interference between each other. The 2-way Radio transmission can potentially damage the receiver board in the RAD pack if it is a few inches in proximity.