FDM-DUO-R Shortwave Receiver


After the great success of the FDM-DUO transceiver the manufacturer now offers the "R" as a receiver — as to be expected by Elad in a sleek italian design and equipped with top-notch technology.

The FDM-DUO-R is a shortwave receiver which uses state-of-the-art SDR technology, but which can be used like a traditional radio. Familiar operating controls like a large VFO knob, dials for volume, filters and other functions as well as pushbuttons for often used settings lend the FDM-DUO-R an ease of use like a classical receiver. Inner values like a fast AD converter and powerful digital processing capabilities are the basis for excellent reception capabilities, like they are known from the FDM-S2 and FDM-DUO.

A very interesting of the FDM-DUO-R receiver innovation are 10 slots for pre-selector boards, which can be populated by the user as needed. Elad offers various high-pass and band-pass filters, for example to suppress nearby medium wave raadio stations. Band-pass filters are available for the amateur radio bands and help to achieve excellent large signal handling capabilities, suitable even for contest stations. And users demanding even more flexibility can use two empty boards to design their own filters perfectly matched to their needs. By using a clever combination of the two antenna inputs, attenuators, the standard 54MHz low pass filter and the switchable ten pre-selector positions the receiver design offers a lot of possibilities for individual tuning.

The receive frequency range is from 10 kHz to 54 MHz [1]. The two antenna inputs are selected by programmable band edges, so the the right antenna and filter module is selected depending on the frequency. A TCXO is used for good frequency stability, the side band noise of the oscillator is a very low -130 to -136dBc, resulting in a low noise floor and excellent sensitivity. Alternatively an external 10 MHz precision clock reference can be used as master clock. Depending on how the FDM-DUO-R is used - with our without computer - different operating modes are available: without computer USB, LSB, CW, AM and FM, with computer additionally WFM and DRM can be received. DRM is available with the supplied software, no complicated installation of additional software is needed.

The nice thing about the FDM-DUO-R is, that it can be used with or without a computer. Without computer the receiver is an excellent companion for the demanding SWL, even when going portable during a vacation. And when working together with a computer the FDM-DUO-R offers state-of-the-art SDR capabilities like a waterfall display, decoding, recording and much more. The supplied FDM-SW2 software allows the operation of up to 4 receivers at the same time. The manufacturer also supplies an "ExtIO" DLL program, which is required to use the receiver with other software like SDR#, HDSDR, SDR-Radio and more.

Further hardware features of the FDM-DUO-R are worthy of professional radios. The precision clock iput was already mentioned. A USB CAT interfave allows remote control with the right software, the CAT protocol is fully documented. A "Mute" input stops the receiver when a nearby transmitter is keyed, providing seamless integration into an existing amateur radio station. The 9 pin extension port is compatible with the existing extension boards by Elad. Connections for headphones and line out are provided. The receiver requires a 13.8V DC supply, max. current intake is approx. 500 mA.


Frequency Range Rx 10 kHz - 54 MHz RX direct sampling [1]
Connector 2 x PL
External CLock Input 10MHz, SMA
Modes (Stand-Alone, without computer) CW, USB, LSB, AM, FM
Modes (with computer) CW, USB, LSB, AM, S-AM, FM, WFM, DRM
AD Converter 16 Bit
ADC clock 122.8 MHz
Phase noise -136dBc @100kHz, -130dBc @10kHz
I/Q output USB 2.0
Weight ca. 1200 g
Dimensions 180 × 155 × 70 mm

For further technical specifications please see the FDM-DUO-R Usr Manual, provided by the manufacturer at their download site.

[1] The frequency range covers VHF from 76–108 and 136–160 MHz, just like the FDM-S2. To use the VHF ranges a special filter is required, which is currently not available. The manufacturer has informed us that a filter is in preparation. Unfortunately a precise shipping date has not been specified.

Order No.
FDM-DUO-R Elad SDR Receiver 899.00
FLP-500K Elad low pass 500kHz 22.00
FHP-05 Elad high pass 500kHz 22.00
FHP-17 Elad high pass 1700 kHz 22.00
FBP-160 Elad Band pass 160m 22.00
FBP-80 Elad Band pass 80m 22.00
FBP-40 Elad Band pass 40m 22.00
FBP-30 Elad Band pass 30m 22.00
FBP-20 Elad Band pass 20m 22.00
FBP-17 Elad Band pass 17m 22.00
FBP-15 Elad Band pass 15m 22.00
FBP-12 Elad Band pass 12m 22.00
FPCB-3 Elad Filter board 3 pole for own designs 3.20
FPCB-5 Elad Filter board 5 pole for own designs 3.20


In the ELAD FDM-DUO-R Download Area you can find:
FDM-S1 SDR Receiver (Software Defined Radio) with DRM function

Compact SDR Receiver with DRM, range up to 30 or 170MHz!

Elad (Italy) does offer various SDRs for several years. Based on this experience the FDM-S1 was designed as a very compact receiver with many outstanding features. The low power consumption of just 2.2W makes the FDM-S1 an ideal travel companion for your notebook computer. Optionally partially populated boards are available, offering place for many own experiments and improvements.

Like most Hi-End SDRs the receiver uses a direct sampling of the HF radio spectrum, with a sample rate of 61.44 MHz. The signal is analog/digital converted with a 14 bit ADC and processed digitally. The connection to the computer is done with a high speed USB 2.0 cable.

The standard receiving range is from 20 kHz up to 30MHz. When using the 'undersampling' function, the receiving range is extended up to 170MHz, albeit with reduced specifications. A maximum spectrum width of 6.144 MHz can be displayed. As usual with SDRs this spectrum can be recorded and later be used for further analysis.


A special feature of the FDM-S1 is the integrated DRM decoder. Without the need of additional software installation, DRM transmissions can be decoded out of the box. That is much easier than with other SDRs. Of course the FDM-S1 can decode all other standard modes as well: U/LSB, DSB, CW, AM, Synchron-AM, FM, W-FM etc.

The filter width can be set very precisely and individually per mode. And here it is where the experience of the manufacturer Elad shows: even with the smallest filter width setting of 100Hz no ringing can be heard.

Included in shipment is the software FDM-SW1, which offers clean looks, comfortable operation and many inventive features. The patent pending tuning system offers three mouse operated dials fpr 'coarse', 'middle' and 'fine' tuning, resulting in a very precise and fast tuning over the entire range. But tuning can be done very nicely with the keyboard as well. A directly accessible recorder allows storage of received transmissions with a click of the mouse.

Further the FDM-SW1 software allows to define an indefinite number of band segments, where mode, filter and tuning steps are pre defined. Each frequency can be stored in memories, only limited by disk storage space. A transmission schedule for DRM is supplied with the software.

Instead of the supplied software other programs can be used as well. The FDM-S1 works also with the "Studio1" software (non free), as well as with the free (as in free beer) HDSDR software.

The "Ext I/O" connector is used to control extensions of the FDM-S1. This socket offers for example a "Mute" input, used to mute the receiver when transmitting with another radio. Further the ExtIO offers frequency information and various switching signals, to used for example for antenna selection, band filters etc. With these functions the FDM-S1 offers many possibilities for own experiments, unlike other SDRs.

Included in shipment of the FDM-S1 is a USB cable, an adaptor SMA/BNC plus a CD-ROM with the english language manuals (PDF). Size 108 x 27 x 88mm, weight 180g.

As most software the programs for the Elad FDM-S1 are continously developed and extended. For example the manufacturer plans a server component, which will allow remote operations. This server will reduce the required bandwidth, so that slow data lines can be used for remote access. Unfortunately it is not known at the moment, if this software extension will be available for free or as a payable option.

Order No.
FDM-S1 Elad FDM-S1 SDR Receiver incl. Software FDM-SW1 369.00


FDM-S2 SDR Receiver (Software Defined Radio) with DRM function

The SDR receiver FDM-S2 is similar in many areas to the FDM-1: the casing of the FDM-S2 is a bit bigger, the interfaces and connectors are nearly identical, the same SFE experimenter boards (see below) can be used.

The most important difference between FDM-S1 and FDM-S2 is the AD converter and the directly covered frequency range. Because the AD converter of the FDM-S2 is of a newer generation, it is more efficient: it scans faster and with higher resolution. Consequently the direct (without 'undersampling') covered reception range is increased, with the FDM-S2 up to 52 MHz (FDM-S1: 30 MHz). Additionally the new AD converter has a word length of 16 Bit, which allows for a finer resolution and an improved dynamic range. Another consequence of the new AD converter is the improved receiver in the VHF range (with undersampling). This way the FDM-S2 receives WFM without problems and the RDS signal is decoded as well. For better VHF support the FDM-S2 has its own, second antenna input (SMA connector). Please notice: VHF range is not available continuously, but only from 74 to 108 MHz and from 135 to 160 MHz.

Another improvement of the more efficient hardware is utilised by the included FDM-Sw2 software: It can now decode up to 4 'virtual' receivers in the same passband. Adjust every receiver independently to operating mode, filter, volume, squelch and so on.

Differences FDM-S1 / FDM-S2
Sampling rate ADC 61.44 MHz 122.88 MHz
Word length ADC 14 Bit 16 Bit
Direct Sampling Range 20 kHZ — 30 MHz 9 kHz — 52 MHz
Undersampling Range up to 170 MHz up to 160 MHz
Size 108 × 88 × 27 mm 110 × 90 × 40 mm
Weight 180 g 360 g
Price 369.00   525.00  
Order No.
FDM-S2 Elad FDM-S2 SDR Receiver incl. software FDM-SW2 525.00


SFE Experimenter Boards FDM-S1/FDM-S2

For your own experiments, two partially populated boards are available for the FDM-S1 and FDM-S2. This allows to build own extensions like a pre-selector, antenna switch, transmit/receive switch, pre amplifiers and much more.

The boards are partially assembled, and come either with or without relays. On the board the I2C bus of the SDR is available for frequency control, further 7 individual switching signals can be used. The state of each of these 7 signals is shown with a LED for easier debugging. The breadboard space is available for own electronics. The board offers the required supply voltage as well.

Order No.
FDM-S1-SFE-R SFE Board with relays 46.50
FDM-S1-SFE SFE Board without relays 29.00
FDM-S1-BOX Empty box for board 20.00


Elad SPF-08 Modular Preselector Pre-selector for FDM-S1 and FDM-S2 SDRs and other receivers

The SPF-08 is a switchable pre-selector filter for receivers, constructed as a modular system. The device offers the base electronics to control up to eight filter boards, the filter boards can be freely selected by the user. Included in the shipment of the base system is the "pass-thru" board.

Pre-selector filters play an important role in achieving excellent large signal handling caüabilities in a receiver. Especially when living close to strong medium wave or long wave transmitters, or when using the receiver with your amateur radio station a good filter is indispensable. With the use of such filters the first stage of a receiver is relieved of strong out of band signals whoch could lead to unwanted mixing products in later stages. For SDRs the dynamic range of the ADC is much better used when unwanted strong signals are filtered before conversion.

Elad offer ready to use high and low pass filters as well as band filters for the ham radio bands. Further two empty boards are available to build your own 3- or 5-pole filters. This allows the demanding radio amateur or SWL to design filters perfectly matches to his or her requirements.

The SPF-08 Pre-Selector box offers slots for eight filters. Control is done over the 9-pin SubD socket, which is the same as used on other Elad devices (FDM-S1, FDM-S2, FDM-DUO-R). This interfaces (which is not an RS-232 interface) is provided with the frequency information which in turn can be used to select one of the eight filters. The software of the receiver provides means to adjust band edges for each filter, where switchijg should occur. After an initial setup all filter selection is fully automatic.

The case of the SPF-08 is the same as with the FDM-S2 (110 × 90 × 40 mm). Eight LEDs signal which filter is currently selected. The connection is done with SMA sockets, one SMA adaptor cable is provided so the pre-selector can be used instantly with a receiver with SMA connectors like the Elad receivers. Further an interface cable is included, which also handles the power supply. Use of this filter is in principle also possible for other receiver brands as well. For this purpose the serial interface protocol is documented, which is used by the SPF-08 to select a filter. Using an Arduino board to convert this information from another system would be a nice weekend project.

The SPF-08 pre-selector is not suitable for use with tranceivers, only to be used with receivers.

Order No.
SPF-08 Elad Pre-Selector with pass-thru board 159.00
FLP-500K Elad Low pass 500kHz 22.00
FHP-05 Elad High pass 500kHz 22.00
FHP-17 Elad High pass 1700 kHz 22.00
FBP-160 Elad Band pass 160m 22.00
FBP-80 Elad Band pass 80m 22.00
FBP-40 Elad Band pass 40m 22.00
FBP-30 Elad Band pass 30m 22.00
FBP-20 Elad Band pass 20m 22.00
FBP-17 Elad Band pass 17m 22.00
FBP-15 Elad Band pass 15m 22.00
FBP-12 Elad Band pass 12m 22.00
FPCB-3 Elad DIY filter board 3 pole 3.20
FPCB-5 Elad DIY filter board 5 pole 3.20








Alle prijzen zijn inclusief BTW., maar exclusief verzendkosten.
Tussentijdse prijswijzigingen en typefouten voorbehouden.
Fabrikanten kunnen specificaties en uitvoeringen wijzigen.