since July 17, 2002
35GR-RM Monitoring Receiver Unit


3600 MHz

Professional monitoring receiver unit "35GR-RM"


The 35GR-RM is wide band receiver unit intended for commercial / government applications. The receiver has no front panel, it is controlled by connection to a computer via an RS232C and USB rear panel sokets. Tuning from 10 kHz to 3.6 GHz, fast synthesizer provides realistic scanning rates of 120 channels/sec or faster. Strong signal handling is assured with a typical 3rd order intercept (IP3) of +3 dBm.

  • Wide frequency coverage10kHz - 3.6 GHz
  • All mode reception: AM, FM, USB, LSB & CW
  • Superb receiver performance, (S/N > 50dB, NF <14dB)
  • High intercept & excellent sensitivity
  • Multiple IF bandwidths: 2.4kHz, 4.0kHz, 6.0kHz, 15kHz, 30kHz, 110kHz & 220kHz
  • Multi IF signal output (10.7 MHz or 455 KHz)
  • AF-IQ output (12kHz offset anlog IQ)
  • 1000 memory channels and 20 search banks
  • High speed memory scan & search (approx. 120 steps/sec.)
  • Realtime clock
  • Solid-build & compact & cabinet weighting just 1.4 kg

35GR-RM Specifications

Frequency range 10 kHz - 3600 MHz
Receive modes FM, AM, USB, LSB, CW
Intermediate frequencies

374 MHz or 764MHz (1st) /10.7MHz (2nd)/455kHz (3rd)

IF filter bandwidths (3rd IF) 2.4kHz, 4.0kHz, 6.0kHz, 15kHz, 30kHz, 110kHz, 220kHz
Frequency stability < ±1.0ppm @ -10℃ to +75℃
IF output 2nd IF : 10.7MHz (10MHz BW or passed 2nd IF filter)
3rd IF : 455kHz selectable with BNC-jack  
Tuning NCO 1Hz to 999.999 kHz
Preset :
1Hz / 10Hz / 50Hz / 100Hz / 500Hz / 1kHz / 5kHz / 6.25kHz / 8.3kHz / 9kHz / 10kHz / 12.5kHz / 20kHz / 25kHz / 30kHz / 50kHz / 100kHz / 500kHz
Memory channels 1000
Search banks 20
Max. input level +20 dBm (nondestructive)
Inter modulation (typ.)
Freq.(MHz) dynmic
range (dB)
IP2(dBm) IP3(dBm) pre-amp
2.6 88 +40 +14 off
88 +12 +2 on
14.1 90 +34 +30 off
88 +10 +7 on
122.9 88 +63 +3 on
434.9 88 +81 +5 on
650.9 88 +72 +4 on
950.9 89 +76 +5 on
1280.9 90 +43 +7 on
2400.9 85 +36 0 on
IF rejection > 70dB (80dB typ.)
IF suppression > 70dB (80dB typ.)
Inherent spurious signals less than -107 dBm

10kHz - 40 kHz -85 dBm CW 12dB SINAD
40 kHz - 150 kHz -97 dBm CW 12dB SINAD
150 kHz - 500 kHz -107 dBm CW 12dB SINAD
500 kHz - 2.5 MHz -104 dBm AM 10dB S/N
2.5MHz - 30 MHz -110 dBm AM 10dB S/N
30MHz - 3400MHz -117 dBm FM 12dB SINAD
3400MHz - 3500MHz -115 dBm FM 12dB SINAD
3500MHz - 3600MHz -112 dBm FM 12dB SINAD

NF < 14 dB  (10 dB typ. @ AM : BW=6kHz, AGC=off)
S/N > 50 dB  (55dB typ. @ FM : BW=15kHz, dev. = 3.5kHz, -50dBm)
Phase noise
≦-75dBc/Hz @0.1kHz (-82dBc/Hz typ)
≦-80dBc/Hz @1kHz  (-90dBc/Hz typ)
≦-90dBc/Hz @10kHz (-95dBc/Hz typ)
≦-110dBc/Hz @100kHz  (-115dBc/Hz typ)
≦-130dBc/Hz @1MHz  (-138dBc/Hz typ)
Scan rate approx. 120 steps / sec. typ.
Antenna input 50 ohms unblanced BNC jack
Serial data interface RS-232C / USB (UART chip: FTDI FT232BL)
(115.2kbps, 57.6kbps, 38.4kbps, 19.2kbps, 9.6kbps、selectable)
Realtime clock accuracy +/- 20 sec / month @ 25 degrees Celsius
Timer function On-timer, Off-timer, Sleep-timer
Operating temperature range -10℃~ +75℃
Power requirements DC 12V (11.5-16V) @ 970mA Max.
Audio output 1W into 8 ohms : external speaker jack
Inputs / outputs
DC power socket 1
External speaker lack (3.5mm mini jack) 1
Audio line output jack 2
video output jack (unconnected) 1
Accessories soket (mini DIN 8 pin) 1
IF output jack (BNC jack) 1
Reference frequency input jack (BNC jack) 1
Serial data interface 1  (D-sub 9 pin) 1
Serial data interface 1  (USB) 1
Antenna connector  (BNC jack) 1
Dimensions  131 (W) x 73 (H) x 202 (D) mm approx. excluding projections
Weight  1.4 kg

Specifications subject to change without notice or obligation.

ALSETAC 35GR-RM Block diagram
Wide band coverage 10kHz - 3.6 GHz
Super wide band of 0.01~3600MHz covered in SSB, AM, FM(WFM), CW. The 35GR-RM has a function by the output of the high quality I.F. signal, and, width of the I.F. signal can be choice with demodulate mode separately.

32-bit MCU, Fast scanning , Low noise
Plural DDSs are included in 35GR-RM efficiently.
The lock speed of each synthesizer is less than about 2mS. These DDSs and synthesizers are controlled by 32 bits low noise MCU (Micro Control Unit). The MCU performs various control of the hardware, and calculation of frequency fast.

ANT inout vs RSSI voltage +/- 1.5 ppm high frequency stability
The 35GR series uses a TCXO unit which provides +/1.5ppm frequency stability from -10 to +75 degree Celsius. The 10MHz reference frequency can be input from external equipments.

Superior linearity
The 35GR-RM has superioir linearity in wide frequency range like the left image. The receiver performance of 35GR series are almost equal (or better) to measurement test receivers.
The excellent basic performance of 35GR series enables reliable certain monitoring and listening.

AF-IQ output
A 12kHz IF output is provided for a PC sound card based SDR (software defined radio) for signal demodulation by the PC. Typical application includes the reception of DRM (Digital Radio Mondiale) broadcasts.

Various commands
The 35GR series has commands more than 100. Other than the basic control of receiver, control of memory channels & search banks, high-speed reading of the signal strength can be performed through commands. The 35GR series should be utilized in various systems.

RTC Real-time clock
independent RTC is installed. The function of RTC can do practical use by various systems, such as time-stamps of monitoring records.

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