Briefly about the Caltta PM790 DMR mobile transceiver
For work radios, there are certain requirements that can be considered basic for both a car-mounted mobile and a desktop base station.
Such requirements are, for example, a rugged exterior design and a strong and clear sound. In addition to voice and data services, the Caltta PM790 also offers a variety of customized features to handle different types of tasks. The Caltta PM790 DMR is a highly versatile device.
- Caltta PM790 mobile radio with 2.0" display, GPS, Bluetooth compatibility, choice of UHF 400-470 MHz or VHF 136-174 MHz frequency bands
- Mounting console
- Handheld microphone (keypad)
- Microphone hook
- GPS antenna
- Power cable
Programming of the device can be done by the technicians of Anico upon request after purchase, but a data cable can also be purchased for the device if you want to do it yourself.
Assembling the unit should be a straightforward process, the connections are clear. What is worth paying attention to is the microphone connector on the front of the radio. It's worth looking closely at the connector pins and the mounting tabs; pay attention when inserting the connector.
Exterior and controls
The housing of the device is made of a robust, solid aluminium, which also has a plastic cover, giving it IP54 protection. This makes it resistant to dust and moisture, helps keep it cool and makes it extremely durable. It weighs approximately 1.4 kg. The IP protection can be seen right at the handheld microphone jack. The sturdy half-turn plug, which connects with a clamp, is waterproof thanks to a rubber seal.
The radio buttons are large enough to be easy to press even when wearing gloves. We've also got three programmable buttons that can be configured to our own needs via the CPS program.
The large 4 row 2.0" TFT LCD, 220*176 colour display gives a high-contrast image. It is also clearly visible in daylight, but you can also switch on extra backlighting if you feel the need.
Menu and functions
The radio can be customised to the maximum using the CPS program, allowing you to adapt the menu to the tasks/work in hand. If necessary, the menu can be "fully dimmed" so that only the most important functions are available.
A unique menu is displayed on the screen in both DMR and analogue mode. Pre-programmed functions can be switched on and off in the menu. The menu functions are very similar to those of the PH690 handheld DMR radio, except that there is no vibrating call alert. Encryption options are also available in the menu, and these are compatible with several other manufacturers' encryption options. This feature can be purchased as an optional license.
The front panel of the radio has a speaker with a power of 3W. If this is not enough, a 6W external speaker can be connected to the device via the rear panel connectors. Speaking of audio features, it's worth mentioning that Bluetooth 4.2.es connectivity is also available, so you can easily connect a wireless speaker or a headset with a microphone. The radio is also equipped with a VOX function, so you can automatically start transmission by speaking into the microphone.
The transmitter can be used with almost any Bluetooth headset, so you can even pair it with a car speakerphone. Luckily, Caltta makes several types of headsets and handsets for the device. Most of these are also compatible with eChat internet-based transceivers. Most of them also have a PTT button, which can be used to start a call immediately. The non-factory headsets do not have a PTT button, but Caltta has found a solution for this. Drivers can benefit from a Bluetooth PTT button that can be attached to the driver's finger, so they don't have to let go of the steering wheel to use the radio while driving. Bluetooth also has other functions: in the future it will also be able to communicate data. A Bluetooth GPS connection is under development, which will hopefully allow you to connect a wireless external GPS receiver to the device.
The device also excels in positioning, as it can use not only GPS but also Beidu.
The radio comes with an external GPS antenna with a magnetic base and a long cable. Despite the antenna's small size, it does its job indoors.
But why is GPS useful in a mobile radio?
Thanks to positioning, we can track the exact location of the devices using the repeater through Caltta's Dispatcher program. In addition to GPS coordinates, the radio also transmits the speed of travel.
In addition to the dispatcher map, the radio has another useful feature, the GPS DMO function.
In DMO, or simplex mode, the radio communicates without a repeater. In this case it is also possible to share the GPS position of the users, but without the Dispatcher program. Both the PM790 and PH690 have an optional feature to send their position to each other during DMR transmission.
In this case, the GPS coordinates of the transmitting radio are displayed on the display of the receiving radio, or a bearing and distance data is displayed, depending on the programmed configuration. Within a range of 3500 meters, the radios will display fairly accurate data.
This feature can be particularly useful in areas without infrastructure, especially for search and rescue units or users engaged in similar activities.
SFR /Simplex Frequency Repeater/
This feature is a repeater mode that is compatible with some DMR systems other than Caltta. In DMR mode, this function can be optionally enabled in 2nd generation Caltta devices. In essence, it functions as a repeater in SFR mode using a single frequency.
In Tier 1, it receives DMR audio and data traffic, and in Tier 2, it can transmit this to the radios in SFR mode at 90ms intervals. Currently, the 2nd generation PH690 and DMR devices can use this function. With this feature, we can extend the range of radios without installing a repeater that occupies 2 frequencies. Not only is this cost effective, but it also saves on frequency spectrum by using only one frequency. Whether you are on a site or in a hilly area, the range of your handheld radios can be extended at the touch of a button without any problems with the range of the SFR repeater radio.
Caltta Technologies has added a number of available licenses to expand its DMR transceivers’ feature set. Call record is normally available on similar DMRs, but on the Caltta PM790 transceivers, it is available in analogue mode as well as in digital mode. There is also a live recording function.
For the record, we need to use a special 4GB Caltta memory card, which can store up to 200 hours of audio for later use. If the SD card fills up, the oldest recording will be erased. It will always be replaced by the latest recorded content.
Data Port SP26 Telemetry
Don't forget the data port GPIO on the back of the radio. While on Motorola mobile radios a special connector performs this role, Caltta has built a more common connector into the radio. The main advantage of this is that a mating pair for the data connector can be easily obtained. This connector can also be used to retrieve various telemetric data from the radio. You can control the GPS via the connected switches or even send SMS messages via an external command.
Attractive appearance, easy to use, with the advantages of analogue and DMR modes. Many extra features are available right now, and more are on the way. It's important to highlight that with the development of the eChat system, Caltta DMR repeaters will also be able to be linked to network radios. This will allow the Caltta PM790 to connect to even a remote eChat user, and the eChat Dispatcher will also be able to see the position of the DMR radios.
With the arrival of the PM790 mobile transceiver, a very useful addition has been added to the Caltta DMR range.