The Malahit DSP2 offers very much options for configuration. Today we look at the HARD menu:
Hard menu options:
ENC reverse: Change direction for decoder buttons 1, 2 or both buttons
PWR ANT: Bias Tee voltage for a antenna or pre amp can be activated. Voltage is always the cell voltage from about 3,7v – 2,5v
Vbat control: Configuration for the cell voltage, with “Low”, the receiver don´t have a protection for undervolting. Use better “Standard”. With “Standard” the receiver shutdown under 3,3v.
SW antenna: 50 Ohm for a standard antenna, Hi Z for SW with a antenna like a telescopic one
PREAMP: Enable or Disable PreAmp. ith the PreAmp you can make the signals stronger
ATT: Attenuator, more dB the signal is weaker. It can help for strong signals
RF GAIN: With this option you can change the gain of the receiver, higher number for a stronger signal. To much gain is not good for the signals, because the signal are to strong
LNA/MIX UPGR: Gain reduction, if you enable this, the gain is weaker, responsible for enabling or disabling gain reduction
MIX GR: Gain reduction, if you enable this, the gain is weaker, responsible for enabling or disabling gain reduction
F correct: If you have a frequency shift, you can controll it with this function
Sm correct: You can control the sensitivy of the S Meter
BEEP LVL: Level of the beep sound of the controls
Ind type: Change from SNR to dBm. “Signal to noise ratio” is an indicator of the signal quality. dBm is a indicator how strong is the signal
Activity timer: The Malahit DSP2 shutdown after the time is configured
Pre Gain: You can control the gain of the PreAmp, lower number for a stronger signal (0 is the strongest). To much gain is not good for the signal
The Dynamic Retro Scale of the Malahit SDR is a very nice feature and it can be activated:
Change the frequency to to W-FM range of your region
Change the mode to W-FM
Now you shuld see the Dynamic Retro Scale windows. If you see the waterfall or the RDS data screen, touch on it (for the RDS data screen, the part on the bottom, which is marked on the picture below), until you see the correct screen.
Malahit DSP2 – Dynamic Retro Scale – Region
At first you must set your region, because both regions have diffrent ranges. Click on the “VISUAL” menu and set the option “Retro Scale”:
European (87,5-108 MHz)
Japanese (75,1-94,9 MHz)
Dynamic Retro – Hidden configuration menu
You can access the hidden menu, if you touch on the space which i marked on the picture:
Dynamic Retro Scale – Configuration menu
In the configuration menu you can find manyoptions:
Auto search for all stations in your near (maximum number of stations is 69)
Add / Edit Station (Add new stations and edit stations added or found with auto search, seven characters, numbers, Latin, Cyrillic)
Rename of the scale (change the name of the scale)
Clear scale (delete scale)
Change to another scale (switch to another scale)
Load a preset (presets which created by the autor)
Change the color (green, yellow or white scale)
Dynamic Retro Scale – Auto Search
With the “Auto Search” you can search for all stations which you can receive. The Dynamic Retro Scales can show the stations after the auto search. If the search found a station, it shows the message “PILOT-TONE DETECTED”. There is a limit of 69 stations. The search process is looking like this and takes about 5 minutes:
After the search is finished, you can see all stations the search has found and you can save the result as a new scale:
After the scan is saved, it´s look like this:
Problems with auto search
If you find too much or too less stations and “WMF Stereo” is enabled, try to activate the headphone. Perhaps it can also help to connect a headphone to the audio out socket. WMF Stereo can only work with a headphone, because without the pilot tone can´t be determined.
Thanks to Peter!
Dynamic Retro Scale – Change Color
Here can you change the color of the Dynamic Retro Scale:
Yellow
Green
White
Dynamic Retro Scale – Add / Edit stations
Here you can:
delete stations
add new stations
rename stations
Possible are seven characters, numbers, Latin, Cyrillic:
The arrows on the screen allow you to change the station name. Above the arrows there is a double window, on the left is the frequency of the station, on the right is the name. By default, after auto search or manual search, the name matches the frequency. Pressing the right arrow will not be able to change the frequency, but you can change the station name.
Dynamic Retro Scale – Rename Scale
Here you can rename the name of your scales. Possible are seven characters, numbers, Latin, Cyrillic:
Dynamic Retro Scale – Clear Scale
Here you can delete the scale you want:
Dynamic Retro Scale – Load Preset
Here can you load a preset from stations from some locations:
At first: You can´t do any permanent damage to the Malahit DSP2. If the firmware updates fails, the Malahit DSP2 remains in the DFU mode an can be flashed again.
Malahit DSP2 – Firmware Download
I have received permission from Georgiy to upload the firmware to my server. You can download it here:
You can found the chagelog on the bottom of this page.
Malahit DSP2 – Firmware Update – DFU mode
At first you must start the Malahit DSP2 in DFU Mode:
Push the two encoder buttons at the same time and hold until step 4.
Push the power button
Release the two encoder buttons
Release the power button
If the LED of the Malahit DSP is blinking green and red, it is in DFU mode
If it don´t work, do it faster. If it is to slow, it don´t work.
Now the Malahit DSP2 should be in the DFU mode. You can plug in the USB cable to Malahit DSP2 and computer. If you open the device manager in Windows 10, you should see this:
Please note: You need a USB cable with data cables. A USB cable only for charging isn´t working.
Now you have to click on the “Erasing and Programming” button:
Now you can select the firmware file do you want to upgrade (you find all possible versions on the top of the page, extract the downloaded file first) and select the checkboxes “Verfify programming” and “Run after programming“. The firmware file can be a hex or a bin file, both file types are working.
At the end you must press the button “Start Programming“.
If you get this error, try to flash the same firmware file a second time. Perhaps you have to reconect the Malahit DSP2 to the computer to do it. Keep calm, the device remains in the DFU mode.
Malahit DSP2 – Firmware Changelog – Test 2.10 2021.07.24
fixed battery voltage indication
fixed behavior of encoder buttons at low supply voltage
protection against false switching has been made – for switching on by three, set switch 2 to the On position.
added test function – increased display frequency. This reduces noise and increases the number of frames per second; To enable this function, set switch 3 to On. The function may not work correctly, if so, please let me know
the level of interference from the display is slightly reduced
changed the distribution of frequencies to which the input high-pass filters are turned on
when HiZ is turned on, the power supply of the external active antenna is automatically turned off;
added indication of external antenna power on – now the ANT indicator is highlighted in red if this function is enabled
the algorithm for displaying the picture on the display, slightly reduces the level of interference
changed the panorama display mode from “Pan & WTF Disabled / Enabled” to “Pan & WTF Single / Always”, while the panorama image is now always present, but it is updated once (when the settings are changed) or always.
fixed attenuators bugs
Malahit DSP2 – Firmware Changelog – Test 2.10 SAM 2021.07.31
SAM functionality
Malahit DSP2 – Firmware Changelog – Test 2.10 2021.08.13
corrected voltmeter operation
added SAMU, SAML modes
increased interface display frequency
improved switching between menus – now it does not pause
optimized the WFM algorithm, the receiver began to work faster
improvements made to Pan & WTF Single mode
removed graphical artifact near the SQL indicator
Malahit DSP2 – Firmware Changelog – Test 2.10 2021.08.16
improved suppression of interference from the display. Now in SSB, AM, NFM modes, noise reduction is automatically turned on. This slows down the speed of the user interface, but greatly reduces the clutter! This function is not used in WFM mode.
Malahit DSP2 – Firmware Changelog – Test 2.10 2021.08.17
Waterfall bandwith increased from 160khz to 192khz
Malahit DSP2 – Firmware Changelog – Test 2.10 2021.08.25
added Pseudo Stereo function. Added Pseudo Stereo button to Audio menu
added the ability to switch audio output in the HARD menu – added the Audio out button. Ph + Sp – headphones and speaker, Phone – headphones, Speaker – speaker
added PGA BST function to HARD menu. This function can be useful when receiving strong signals and receiving congestion. When overloading, you must select the Disabled position.
changed the arrangement in the frequency bar under the spectrum
changed the behavior of the receiver with a short press on the power button. Now, with a short press in the receiver, the touchscreen is turned off, the spectrum and waterfall work similarly to the Pan & WTF Single option.
the lower operating frequency has been reduced from 50 kHz to 20 kHz.
Alle changes between 2.0 and all test version to 2.10D are included:
fixed battery voltage indication
fixed behavior of encoder buttons at low supply voltage
protection against false switching has been made – for switching on by three, set switch 2 to the On position.
added test function – increased display frequency. This reduces noise and increases the number of frames per second; To enable this function, set switch 3 to On. The function may not work correctly, if so, please let me know
the level of interference from the display is slightly reduced
changed the distribution of frequencies to which the input high-pass filters are turned on
when HiZ is turned on, the power supply of the external active antenna is automatically turned off;
added indication of external antenna power on – now the ANT indicator is highlighted in red if this function is enabled
the algorithm for displaying the picture on the display, slightly reduces the level of interference
changed the panorama display mode from “Pan & WTF Disabled / Enabled” to “Pan & WTF Single / Always”, while the panorama image is now always present, but it is updated once (when the settings are changed) or always.
fixed attenuators bugs
corrected voltmeter operation
added SAMU, SAML modes
increased interface display frequency
improved switching between menus – now it does not pause
optimized the WFM algorithm, the receiver began to work faster
improvements made to Pan & WTF Single mode
removed graphical artifact near the SQL indicator
correction of S meter was introduced depending on the range. Now the S meter is accurate enough
improved suppression of interference from the display. Now in SSB, AM, NFM modes, noise reduction is automatically turned on. This slows down the speed of the user interface, but greatly reduces the clutter! This function is not used in WFM mode.
added Pseudo Stereo function. Added Pseudo Stereo button to Audio menu
added the ability to switch audio output in the HARD menu – added the Audio out button. Ph + Sp – headphones and speaker, Phone – headphones, Speaker – speaker
added PGA BST function to HARD menu. This function can be useful when receiving strong signals and receiving congestion. When overloading, you must select the Disabled position.
changed the arrangement in the frequency bar under the spectrum
the lower operating frequency has been reduced from 50 kHz to 10 kHz.
span increased to 192 kHz.
changed properties of USB audio devices – now IQ 192kHz, simple audio – 48kHz.
Malahit DSP2 – Firmware Changelog – Test 2.10E 2021.10.08
Fixed the scale with the image often – the scale is made in the color of the panorama, added horizontal lines
Improved retro-scale – brought to v1.10C
EMI reductuin function added: decreased noise by changing display frequency
fixed moving from AUDIO menu to other menus – now without delay
Gradual volume increase on power on
Improved dead band 380-403,3MHz
Changes The encoders work differently – now you can use the audio encoder independently. The settings are changed with the frequency encoder
Sleep time option was removed from Visual menu
added color scheme for waterfall – now there are three modes of work – classic, black-white and white-black
changed color of backlighting of indicators ATT, VOL, FLT
changed work of DC Reject
fixed the logic of switching the window type in WFM, now the type does not depend on working with other types of modulation
fixed error when sweeping the frequency down – now it is impossible to sweep below the minimum frequency
the NCO function has been introduced – now it is possible to rebuild the viewfinder within the spectrum. Added NCO function to HARD menu
the CAT interface has been completely redesigned, the reaction speed has been significantly increased. A reaction to new commands has been introduced. Now you can control the volume, range, type of antenna input, enable or disable LNA.
The radio amateur SV2CZF makes some very interesting antennas and sells them on his website for a small fee: https://www.sv2czf.com
For a long time I had been tempted by the MWA30 (https://www.sv2czf.com/mwa30.html), which is a very small portable mini-whip that runs on battery power. Unfortunately, mini-whips must be well grounded, so I decided to use his latest antenna, the SAR32M. This one works even without good grounding and you can connect an antenna via a whip antenna like a telescopic or a loop.
Features
Reception from 50 KHz to 175 MHz
Built-in rechargeable battery which can be charged via Micro USB port (approx. 10 hours battery power)
A normal whip antenna, like a telescopic antenna, can be connected
A loop can be connected
A loop and a telescopic antenna can be connected in parallel
Impedance adjustment for shortwave
Built-in Pre Amp for amplification
Only suitable for receiving, when transmitting the SAR32M will be damaged directly
How to order
The SARM32M is already shown on the homepage, but cannot be ordered through it yet.
By default, the SARM32M is delivered with BNC connectors. But you can also ask SV2CZF to install SMA connectors
Antenna 94,99 € and shipping 6,99 €. The antenna is shipped in a bubble envelope and passed customs without any problems for me
The shipping took for me from Greece to Germany only 5 days.
Experience in practice
I use the SAR32M mainly with my Malahit DSP2. Here, the SMA32M with the same 70 cm telescopic antenna, depending on the frequency range, can get out again about the 3 S-stages (for example, in the 40 m band). Unfortunately, the reception breaks in from about 50 MHz, so that e.g. 2 m works better without the SAR32M in between.
On the other hand, if you connect a loop, the SAR32M shows its potential. You can compare it well with the MLA 30 +, which also provides very good reception results. The loop made of wire, which is supplied with the MLA 30 +, also fits optimally to the SAR32M. However, any piece of wire or cable can also be used.
The battery life is about 3 times longer than the Malahits DSP2 with a 3400 mah cell. The great thing is that this makes the SAR32M perfect for portable use.
Here are two examples on the 40m band, received with the SARM32M and a 70 cm telescopic antenna. First CW:
Again with SSB with only a 70 cm telescopic antenna:
The performance is very very good.
From inside
On Facebook I found the following picture of the inside view. The legs are firmly glued and usually break off when you try to open the lid (yes, I tried 😉 )
Of course I tested the Malahit with the SAR32M antenna / 70cm telescopic antenna directly on the balcony and was positively surprised what I can receive everything, with a simple 70 cm telescopic antenna.
Here I show you the reception with a 70 cm telescopic antenna, which is adjusted with Hi Z and amplified with the Pre Amp of the Malahit. The reception is really amazingly good!
Here you can see the SSB reception with the SAR32M and a 70 cm telescopic antenna. In the 40 m band, the SAR32M, provides about 2-3 S-stages better reception. Amazing is also the extremely good noise blocker.
2 x 18650 mod
First I tested if the Malahit DSP2 can also be converted to two 18650 cells and it is possible. But on some boards standing capacitors were installed. Here you have to make sure that you push the speaker to the edge to create space to the left.
In addition, a small and deep 2 x 18650 holder should be used, as can also be seen in the picture. Here you have to be careful to shorten the soldering lugs to the housing.
BMS proctection for the 18650 cell and the Malahit DSP2
The Malahit DSP2 has no protection functions, like a BMS but it´s using the TP5056 charging controller. The charging controller has some protections functions while and after charging.
I added a cheap BMS to be safe, that my 18650 cell have a long life and is protected against a short circuit or things like this.
Bias Tee function, e.g. to supply an external Pre Amp
Then I tested the Bias Tee option and found that always the battery voltage is output. So from 4V – 3,3V (if the VBAT Standard options is activated). This could be problematic, because the cell voltage is to low for most devices.
SMA connector
Please note: The SMA socket problems are solved, because the developers are using a new SMA socket.
The only problems I had were related to the SMA connector: The included SMA telescope antenna had a too thick inner conductor and then apparently broke the SMA connector.
I then installed a U.FL to SMA adapter, which I still had at home, in the Malahit DSP2 and since then everything is fine again. Strangely, I had to try several of these adapters, until then one worked. With the others I only had reception when I connected the respective antenna to the SMA connector.
The U.FL to SMA cable used by the developers is extremely short and was installed in a sharp bend. So all the time there was a lot of voltage on the U.FL connector. As you can see on the picture, I used an adapter with longer RG316 cable. I also secured the cable to the relay with a small blob of hot glue to prevent the port from being live.
Better buttons
Nikolay makes very good and high quality knobs, e.g. for the Malahit DSP1 / DSP2. With shipping both knobs cost 13 € and can be ordered from him by e-mail: nickstrannik@gmail.com
Currently I am working on a Bluetooth mod: I will install a Bluetooth board in the housing of the Malahit DSP2, that I will solder to the 3.5 jack output. So I can then use a Bluetooth headphones or speakers, without an adapter to the 3.5 jack socket, to plug from the outside. I soldered together a small housing for the bluetooth board to avoid possible interference.
The board on the picture can work with the 18650 voltage from 3,0V to 5,5V. I can receive and sent sound, but for the Malahit, only the sending part in needed.
Problems with the Malahit DSP2
The software problems like a wrong voltage are already fixed in the new 2,10 test firmwares. The biggest hardware problem for me was the bad SMA socket, but this problem is also already fixed at newer Malahits DSP2.
