Home Receivers


Reuter RDR-Pocket


At the amateur radio show Hamradio 2016 in Friedrichshafen, Reuter Elektronik showed for the first time a prototype of a portable SDR with full range spectrum  "RDR51-Pocket". From the outside, the small device looked promising. Solid housing, cleanly processed and fast display. This small device attracted many visitors. As a result, Burkhard Reuter decided to build the "Pocket" and offer it in a small series. Burkhard Reuter, the owner of Reuter Elektronik, had set a high goal. A portable receiver with state-of-the-art SDR technology, which should also meet high demands. At the beginning of 2017, the first devices were delivered.
Actually, I should have been one of the first to receive a Reuter Pocket for testing. But procurement problems with the components and unexpectedly many pre-orders pushed the lending of the Pocket very far back. Mr. Reuter contacted me in early November 2017, he could finally provide me with a fully equipped pocket. It was not a week, the device was there.


Unpacking and inspection

After opening the neutral box, the supplied accessories come to the fore. Everything well packed in bubble wrap. Then a black protective bag is fished out of the box. Inside is the Pocket, additionally packed in a plastic bag.
The trained eye immediately recognizes the perfect workmanship! The case of the Pocket is made of an aluminum / magnesium alloy. This has the advantage that the interference of the installed electronics is significantly reduced and the mechanical stability is increased. Reuter Elektronik has already shown with other recipients that high-quality workmanship and the selection of the best materials are part of the company philosophy.
The operating concept is like the big brother RDR55. All settings are made via the 4.3 inch touch screen and the scroll wheel. In the middle of the scroll wheel is the on / off button. If you press this for three seconds, the device turns on. After a short start-up phase, the user interface appears. This is largely like that of the tabletop devices. The Pocket can also be used as an amateur radio if you order it with the appropriate module. But then you have to do without FM and DAB +. For both together there is too little space in the small housing.
The Pocket works on the same principle, the frequency-based way of working, like its big brothers. This operation has the advantage that the audio is derived directly from the visible spectrum. This means that the audio and spectrum are absolutely synchronous, ie real-time! Time-based SDRs, such as Winradio, Perseus, etc., always have some delay between the audio and the spectrum. A good description of the frequency-based working method can be found here <Link>.
Thanks to its compact dimensions and built-in batteries, the Pocket becomes a portable device. He can be easily transported in the jacket pocket. Due to its design principle, the Pocket has no built-in receiving antenna. Except a WLAN and Bluetooth antenna, which is integrated in the appropriate modules. This means that for portable operation you should have at least one telescopic antenna with SMA connection.

The main features of the Pocket

-- Frequency range : 1KHz - 30 MHz, 50 - 71 MHz, 87 MHz - 110 MHz, 130 - 156 MHz, 174 - 240 MHz (DAB + reception only)
-- Bandwidth filter: 10Hz - 20KHz freely adjustable in 40Hz steps. Depending on the audio resolution.
-- Frequency - based modes: Sync - DSB - LSB - USB - EUSB - SBCW - CW
-- Time based modes: AM-E - FMN - FMW - USBQ - LSBQ - DIGI - DSBQ
-- Tuning range: arbitrarily adjustable from 0.5Hz - 999.999.5KHz / direct selection of preprogrammed step sizes
-- Visibility of the spectrum: Smallest viewing width: 6.2KHz, widest viewing width: 52MHz (option)
-- FM mono / stereo with wide function and RDS
-- FM filters: 38KHz-S, 50KHz-S, 80KHz-S, 80KHz-HQ,, 120KHz-S, 120KHz-HQ, 240KHz-HQ, 300KHz-HQ (S = Steep filter edges, HQ = Flatter filter edges for optimum listening pleasure )
-- DAB + reception in mono or stereo
-- 256 memories
-- Passband tuning
-- AutoNotch & manually adjustable notch filter
-- Noiseblanker
-- AGC: increase and hold time adjustable
-- 2x 14bit ADC model B2 (review sample) - optional 2x 16bit on model C2
-- Real-time spectrum and waterfall
-- Fast and very bright TFT- display with 4.3 "(109 mm) diagonal, WVGA 800 x 480 pixel resolution
-- GPS module for frequency calibration and information on altitude, coordinates and time in UTC.
-- WLAN module for wireless firmware updates & screenshot functions
-- Bluetooth module for connecting wireless speakers or headphones
-- Bandpass filter for LMK (1-10MHz, 10-30MHz) or bypass
-- Bandpass filter for the 6m range (50 - 70MHz)
-- FM bandpass filter (87 - 110MHz)
-- 2m bandpass filter (130 - 156MHz)
-- Bandpass filter for the DAB + range (174 - 240MHz)
-- 8 GB flash memory for audio recordings
-- SMA connections for LMK, FM & DAB + reception, as well as WLAN & GPS
-- Lemo socket for the power supply
-- 3.5mm jack sockets for headphones / speakers, microphone & Morse key (with built-in transmitter)
-- 2 built-in speakers for stereo output
-- 2 batteries with 2600mAh
-- Dimensions: 158 mm x 110 mm x 30 mm (WxHxD)
-- Weight: 700g

Included supply:
-- Transport bag
-- Adapter from SMA to BNC (Pigtail)
--PDA stylus
-- GPS antenna with 3m cable
-- Charging and power supply cable with Lemo and banana plugs
-- CD with software



Put the Pocket in working position

To get the Pocket into a comfortable working position, there are three options. The first installation aid is from Reuter Elektronik <Link>. This is a bent acrylic glass. Just put the pocket on the short thigh. The second variant comes from the 3D printer of a resourceful radio amateur. The two feet are simply pushed over the shell of the pocket. These stalls are the smallest and are very suitable for portable use. These fit well into the bag pocket. The 3D file can be downloaded here. <Link> The third variant is a universal positioning aid "Modell München" for many portable devices. It is available at Wellenjagd.de. <Link> A little tip at the point: With the device stand of Reuter and Wellenjagd. I recommend to attach the pocket with Velcro to the stand. This prevents the device from slipping off. Of course you can also hold the device in your hand ...



Working with the Pocket

The inexperienced owner of such a high-tech device should keep the instructions ready. Because a few functions must first be understood correctly in order to fully exploit the performance of the Pocket. Of course you can easily operate the Pocket in the default setting.
If you tap on the button Menu, a dialog opens with submenus. If you then tap on the button Setup, you get to the most common settings of the Pocket. Here you can set a variety of function parameters. Special attention should be paid to the function "Impedance 0-71MHz". Here you can set 0Ohm, 50Ohm and ~~. Default value is 50ohm, for eg active antennas and dipoles. 0Ohm is intended for small antennas, eg a telescopic antenna for the road. The infinite setting ~~ is intended for low frequencies in conjunction with a short antenna, because in this setting the signal is amplified by 14dB. The other special setting is the "Resolution Audio (Hz / Bin)". This setting affects the sound and setting options of the spectrum-based demodulators. It determines the audio resolution associated with the adjustable bandwidth. 3 levels are possible. At 10Hz resolution the maximum adjustable bandwidth is 5.1KHz. 20Hz results in 10.2KHz and 40Hz results in 20.4KHz bandwidth. The latter should only be used if you want to listen to strong broadband channels over 11KHz. Default value is 20Hz / Bin. This is sufficient in most cases. For extremely weak stations 10Hz / Bin can bring advantages in the intelligibility. That's the finest resolution.


The main discipline of the Pocket is the reception from 1KHz to 71MHz. For this frequency range and frequency-based operation, the device provides a variety of functions to optimize reception. One can confidently call the variety of functions professional. Because nothing is missing. Various functions are not available in the time-based mode of operation. For example, the NB, DNR, Notch and PBT. The bandwidth selection is limited. But the pocket sounds rounder, fuller. Almost like a tube receiver. The FM band, which includes the 2m amateur band and DAB +, is not generated by the frequency-based method, but also by time-based methods (like traditional SDR's). So here are also certain restrictions that are not significant. With the HQ (High Quality) filters, which are optional for FM broadcasting, there are eight bandwidth filters to choose from, which are absolutely sufficient for demanding broadcasting enjoyment. For the time-based modes AM-E, FM etc. there are 15 bandwidth filters available. These filters are not hardware, but DSP filters!

Due to its compact dimensions, the handling is getting used to. The touch screen can be operated with the fingers or with a PDA stylus. The latter is the better choice because some buttons on the display are very small. The most obvious is of course the fast working and very sharp spectrum. Even if you tune through the tape, no delay is noticeable. I do not know any other SDR with such a fast spectrum. Next comes the Icom IC-R8600.

With the PDA pen tapped on the frequency display, opens the input and memory dialog. Times a frequency in the 49m band set in the "Synch" mode. Immediately the station becomes audible. "Synch" actually means AM-Synchron. This mode is the standard mode, so to speak, if you want to hear AM station. The signal is detected and synchronized immediately. A normal "AM" like analogue radios does not exist here.
The very early models of the RDR devices had a slightly tinny audio. The Pocket with the latest hardware and software, however, sounds analog in the frequency-based mode of operation! No artifacts, no canned sound! What usually only stands out in direct comparison, is the very low noise of the Pocket. A real treat for the ears. For very weak and poorly understood broadcasters, one can fall back on a good tool. The "surround" function. Once activated, it can significantly increase intelligibility and produce a stereo-like sound.

If the reception is undisturbed, you can switch to the time-based modes. AM stations can then be heard in "AM-E". The bandwidth filters have flatter filter edges and sound rounder. The audio gets more fullness and sounds warmer. Also for the sidebands (LSBQ & USBQ) there are own demodulator doors.

Frequency-based (Spec-Based)

With the Pocket on the way

As the name suggests Pocket, the small fits well in the jacket pocket. To be able to listen to the radio on the go, all you need is a telescopic antenna with an SMA connection. The Diamond SRH789 fits very well with the Pocket. The SMA connector of this telescopic antenna is designed in such a way that the SMA cable gland does not release itself when turning the antenna. Because the SMA union nut is free-spinning. Be careful when buying the SRH789! There are fakes in which the SMA union nut is rigidly connected to the antenna. Only the original is worth the money.

If the antenna is screwed on, you should set in the menu the input impedance to "0Ohm", so that the full sensitivity can be used. I took the pocket on some walks and felt it on the tooth. The reception was largely impeccable. The feared disturbances by the device itself, kept within limits. At a distance of about 46KHz, peaks were seen in the spectrum. These disturbances were mainly generated by the display. In the power management dialog there is the function "spread spectrum" which makes it possible to smooth these disturbances. But that is to the detriment of the background noise. This increases a bit. The Pocket is really fun with a powerful antenna. For example, with an active dipole. I put together a portable set in a suitcase for portable hardcore reception. The whole thing is set up in 5 minutes. So far from home disturbances, I can enjoy distant and weak stations. The two built-in rechargeable batteries last about 5 hours in headphone mode.



The audio comparisons from VLF to 30MHz

Although the Pocket is designed for portable use, it can be easily operated on the station antennas. The usual hobby antennas he tolerates easily. Therefore, the audio comparisons were made at home in the Shack, which was also more convenient.

The Pocket can be tuned from 1KHz. Reception is only possible from 9KHz, because the antennas are not received so far down.
To be able to assess a device, you need a comparison device as a reference. For this, the proven Winradio G33DDC Excalibur Pro offered. This is one of the best SDR's, which is under 2000 € to get.

Below are the audio comparisons between the Reuter Pocket and the Winradio G33DDC Excalibur Pro. To hear the differences is the use of a headphone a must. Both devices were operated with the same settings and were supplied with the antenna signal via the antenna distributor of Elad ASA-62. The audio was recorded via an audio switcher with the recording software Audacity. The shots were not edited, just cut to the appropriate length.

Used Antennas : Datong AD370 & Crossloop-RLA4E/2

Second 0 - 10> Reuter Pocket
Second 10 - 20> Winradio G33DDC Excalibur Pro

The reception of the alpha signals at 11.9KHz, 12.65KHz and 14.9KHz compared to the G33DDC Excalibur Pro. Reception antenna Datong AD370.

Alpha Signale
ERTU Shamal Said Misr
Pocket mit Surround
Radio Tajikistan
VoA Botswana
Radio Cultural Amauta
Pocket mit Surround
RAF Volmet
Voice of Iran
Shannon Volmet
Reach Beyond Australia
Gander Radio
Radio Kuwait
CHU Ottawa
Voice of Turkey
Radio Habana Cuba

The audio comparisons of long, medium and shortwave were made with the Kreuzloop RLA4E / 2.

The reception on FM

With the Reuter Pocket you can also comfortably listen to FM radio. It receives from 87 - 110MHz. There are eight bandwidth filters available. With the "HQ" filters, it is also very good to enjoy strong incoming stations almost noise-free. With the function "Stereo Wide", the stereo base can be doubled. This gives the already good-sounding audio even more sense of space. The RDS decoder works quite fast and sensitive. It indicates the PI code of the transmitter, as well as information on faulty blocks corrected by the decoder. For FM Dxers and specialists an interesting thing!

On a Superdiskone the pocket receives acceptable to good. At times he overrides something. This is noticeable by the red glowing frequency display. Also in the spectrum, unwanted peaks appear. With the attenuator can get this under control. Active antennas can not stand the VHF receiver. It is best to treat it to a small passive outdoor antenna or a telescopic antenna on the device itself. Then the VHF receiver receives perfectly. If you have the antenna history under control, even FM-DX is possible with the Pocket. With its narrow bandwidth filters it is possible to make weak transmitters audible between the thick brads. There are two ways to represent the spectrum. Either normal, where you can see the stations in 100KHz grid, or you can set it so that you can represent the MPX (multiplex) signals. The latter only works with stations that transmit in stereo or when switched to stereo.


DAB + reception

Besides so many features, the Pocket still offers DAB +! The Pocket receives the DAB Band III (170 - 240MHz). This does not work the same way as with the traditional DAB + receivers. In the tested software version V2B8, the Pocket does not permanently store the stations. When accessing DAB +, a search is always triggered and lists all receivable stations in a list. This list can be moved with the scroll wheel. To call the transmitter is simply typed on the appropriate field. The search takes between 30 seconds and one minute. Depending on how many stations are found. The reception works very well. The playback is absolutely noise-free. In the tested software version not all data packets are processed yet. Pictures can not be displayed yet. Text, however, already. When searching on the Superdiskone 141 channels were found. Outside with the telescopic aerial, there were still 105 transmitters. In addition to the station name, data of the ensemble and station identification are also displayed.


Recorder function

The present device has an 8GB flash memory that can be used for audio recordings. This takes up in 24bit resolution. A useful thing, if you want to log very weak signals and the station has not noticed. These can then be played.




I had the Reuter Pocket over two months in the test. He was present at the DX-Camp in the Holzerbachtal near Solingen and was tried there on all antennas. At home, too, I used it intensively and compared it. Mainly with the Winradio G33DDC Excalibur Pro. The Pocket could easily handle the hobby-usual antennas. Except the NTi Megactiv 305 and the MiniWhip caused him some problems. These antennas caused short-term overloading the ADC. The frequency display occasionally turned red, but there was no audible intermodulations or increased noise. The reception differences to PC-based Winradio were minimal. The Winradio has a slightly lighter rendering that made very weak signals a little bit more understandable. The performance of the little pocket has surprised me completely and convinced! Excellent sensitivity, very low noise, extreme selectivity and an almost incredible flexibility in signal processing leave nothing to be desired. Add to that the FM, DAB + reception and the excellent workmanship. What did not work in the test phase was the Bluetooth function. The driver was not available yet.

The first pocket-sized portable direct sampling SDR with the performance of a semi-professional receiver. The Reuter Pocket is an exceptional device! This device concept is currently unique in the market.

As you can only say: absolute top class!

Posted: 27.12.2017

↑↑ Home Receivers