Aor ar5700d digital communications receiver, advanced digital communications receiver, 9 kHz-3700 MHz analogue & digital modes, 10 digital modes : tetra, p25(phase 1+2),dmr, mototrbo,dpmr,nxdn,d-cr,d-star, Alinco, Yaesu. Automatic detection of digital modes during scan and search, up to 2 mhz wide digital I/q output, modes: fm, fm-stereo, am, synchronous am, usb, lsb, cw, analog I/q, FM video, d-star / gmsk / ambe dv mode only, yaesu / c4fm / ambe+2 v/d narrow mode only, alinco / gmsk / ambe ej47 (f1e) mode only, d-cr / c4fm / ambe+2, nxdn / c4fm / ambe+2 6.25khz mode only, p25 phase 1 / c4fm / imbe conventional mode only, dpmr / c4fm / ambe+2 tier 1 only, dmr / c4fmx2 / ambe+2 tier 1 and tier 2 only, tetra direct mode (t-dm) / π/4 shift qpsk / acelp, tetra traffic channel (t-tc) / π/4 shift qpsk / acelp, mototrbo, dpmr, nxdn, d-cr, d-star, Alinco, Yaesu, OVERVIEW The AR5700D is a high-performance wide-band communications receiver. As well as resolving the common modes of AM, SAM, FM, WFM(S), SSB and CW it also decodes the TETRA (including Direct Mode, Traffic Channel and GSSI user group filtering), DMR, NXDN, D-STAR, DPMR, APCO 25, YAESU and Alinco EJ-47 digital voice modes. It sports a backlit LCD main display with a frequency span of up to 10MHz.

It has provision for computer control, and free software is provided along with the required USB to PC leads. With a frequency coverage of 9kHz to 3.7GHz and multi-mode reception, the AR5700D has all the makings of an extremely capable receiver. FEATURES The AR5700D comes in a smart-looking case not dissimilar to the AR5000, AR5001, and AR6000. The front panel markings appear prominent with the buttons, controls, and display standing out well. The unit is reasonably weighty at around 5kg and measures approximately 225mm x 110mm x 330mm. It has a carry handle on one side and four feet on the opposite with a retractable tilt bail on the underside. The overall black finish contrasts with the grey trim and white lettering to give a very neat appearance. 

The characters on the dot matrix LCD display, while looking pixelated, stand out well. The analog signal strength meter is on the small side but easily readable and has a pleasant amber backlight. Signal strengths are repeated in dBm or dBu on the LCD display. The front panel controls are of good quality and consist of three rotary encoders – one volume, one squelch and one acting as a sub-dial – and the main tuning control, which is free running. The front panel also has a selection of pushbuttons, all having more than one function, there is a 3.5mm phones socket, an SD card port, and also an 8-pin mini-DIN accessory socket. 

On the rear panel, there are two Type N sockets for aerial inputs. Ant 1 is for frequencies over 25MHz and Ant 2 is used for the full coverage of the radio, although please note that this changes when using the software (see below). There are sockets for IF out (BNC with 15MHz bandwidth), 10MHz external reference clock input (SMA), video out (phono/RCA), USB (type B) for I/Q and Computer Control, 9-pin D for receiver serial control or an optional Ethernet controller, Aux 2 8-pin Mini-DIN (provided for ‘future applications’), and two 3.5mm jacks for speaker and line output. 12V DC power to the set is taken from the supplied external mains unit which plugs into a 2.5mm socket. 

The main DC power-off switch is located on the rear panel. We found little information available on the inner workings of the set but the sales literature states that the radio is fitted with four Renesas SH2 CPUs, three Analogue Devices Blackfin DSPs, one Analogue Devices ADSP-2185 DSP, and four Intel Altera Cyclone FPGAs. These devices provide signal processing, demodulation, and decoding. It is claimed that 63/65MHz sampling frequencies are used for the analog to digital converters. Clearly, the AR5700D benefits from some advanced technology. There are 33 RF bandpass filters and AOR claims IP3 figures of +20dBm at 14.1MHz Preselector off, +6dBm at 50MHz, and +5dBm at 620MHz Preamp off. 

There is a provision for instant recording and playback to the supplied 16Gb SD Card. Two thousand memory channels are provided in 50x40 banks and these can be customized to hold between 5 to 95 channels per bank in the form AOR AR5700D www.wrth.com 11 REVIEWS AOR AR5700D of ‘dynamic memory’, allowing banks with only a few entries to be set aside for specific uses. There are also 40 search banks, and 1230 pass or priority channels can be set. The supplied manual describes the basic operations.