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Jun 2nd, 2023, 6:08am
News: Welcome to the linuxslate.com forums. May 2020: Forum registration has been disabled due to recent advancements in bypassing captcha's and the resulting increase in spam on the forums. Registration may be re-enabled at a later date. In the meantime, if you would like to register, please email "john" at this domain, and I will manually create an account for you. Registration is for legitimate and relevant discussion only. Misused accounts will be deleted without warning.

1  Original Projects and Builds / Other Builds and Projects / Re: 7591 Amp Build (from Rowe/AMI R-4359)
 on: May 29th, 2023, 8:57am 
Started by Administrator | Post by Administrator
In my last post, I stated that this project was "essentially" complete.  Now I will demonstrate why I didn't just say "compete".
After some use, and testing, I decided that I was not happy with the VFD (Vacuum Fluorescent Display) Spectrum analyzer that I had purchase and installed in this amplifier.  Here are some specific complaints I had about the VFD SA:
  • It put significant noise back onto the audio lines.
  • It defaulted to a Clock mode. I was not trying to make an overpriced clock radio.
  • Testing showed that the spectrum analyzer was highly inaccurate, and did not respond at all over significant parts of the audio spectrum.
  • The display was "OK" , but again, for what is supposed be a "high-end" piece of audio equipment, I wanted better.

After some research of available bare VFD SA boards available on AliExpress, I found out the board I had bought was essentially "counterfeit", or a poor quality version of a board known as "AK2515".
On big hint is that the knock-off, or poor quality VFD's do not even specify a frequency range in the AliExpress advertising.
But even "real" AK2515 boards still have the clock mode.
A little more research lead me to this unit from Douk Audio:

This unit does have a full set of advertised specifications.  It does not have a clock mode, and while there is no question that Douk Audio is still a "Chi-Fi" company, I at least trust them to have a little better quality than most of the other Chinese vendors.
The board still needed some connector modifications, and I had to drill a new hole in one of the support brackets, I was able to install the Douk Audio VFD into the amplifier without too much difficulty.
The new display is slightly larger, and noticeably brighter and "bolder" than the previous one.
I will point out that I still consider all of these to be highly inaccurate for actually measuring audio frequency -- especially in stereo display mode.
First, there are 25 bars, and there is no "blank spot" or skipped bar in stereo mode.  This means that the left channel has 12 bands and the right channel has 13 bands.
Furthermore, these displays don't actually have an analog filter for each band.  They use a microprocessor to do DSP and scan the display.  The result of all of the above is that even if the same pure sine wave signal is fed into both channels, the left and right channels will not display the same levels at the same band anyplace in the audio spectrum.
That said they still provide a visually interesting visualization of the music, and they have to the bright, and attractive color that only VFD's can provide.
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2  Linuxslate.com Reviews & Commentary / Review Discussions / Re: Unbranded Chinese Pocket Geiger Counter
 on: May 12th, 2023, 9:44am 
Started by Administrator | Post by Administrator
There already seems to be a newer version of this Geiger Counter/Ionizing Radiation Detector.
Look carefully at the ads for the following Changes:
  • Metal or Shiny plastic oblong buttons.  Nicer feel, and will not rotate in place.
  • Round pattern of openings on the front for the buzzer instead of the slots.
  • Slotted openings in the back to expose the Geiger Tube.  <-- This is important, and will increase the sensitivity of the instrument.

I strongly recommend purchasing this new version over the version I reviewed.
I am not aware of any software/display changes at this time.
If you have additional information on this new version, or would like to send me a complimentary unit for review, please send me an email at "john" at this domain (linuxslate.com).
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3  Linuxslate.com Reviews & Commentary / Review Discussions / Re: Mini Review DOLCOM GP328 PLUS and discussion
 on: May 3rd, 2023, 2:00pm 
Started by Administrator | Post by Administrator
I have a few more comments about my DOLCOM GP328 PLUS.

Continued from the 1st Post
  • I have not installed the belt clip, but it has an actual metal hinge and spring, and screws into the metal casting that is the chassis (heat sink) of the radio.  (As compared to my  HamGeek FB-8, Reviewed Here, which has a plastic clip with the hinge just being a thin part of the plastic.
  • The "Monitor" button (The button that temporarily opens the squelch) works properly.  It is a momentary button that seems to work very directly.  Other radios have this as a digital toggle, or some sort of software function that incurs delays.
  • Battery life seems very good.  Even with Back Light set to Constant, so that the display never sleeps, a charge will last for many hours of listening.  Of course transmitting at full power will drain the battery faster, but the basic functioning of the radio seems to be very efficient.
  • The instruction manual exceeded (admittedly low) expectations.  While it has only 16 pages, it is an actual booklet style manual with the covers printed on glossy paper.  As delivered with mine, it was English language only, with good grammar. It contains accurate illustrations of the radio and displays.
  • Pressing and holding 0_ displays the battery (power supply) voltage in the lower area of the display.  The normal display returns when the button is released. Like the Monitor function, it's convenient and user friendly, not buried 3 levels down in a menu.

  • As mentioned in a previous post, this radio can scan through both programmed channels and VFO frequencies;  however, there is no scan lock-out or bypass for programmed channels.  This means that if you program in a channel that is always (or usually) transmitting, such as an airport ATIS, or NOAA Weather channel, the scanning will stop on any such channel encountered.  If you want it to scan through a number of channels for any activity, you can't program any "always on" channels.
  • I haven't figured out how to put a space, or even a dash in a channel memory name.  If you intend to leave a dash, and you accidently start entering a character, the only thing you can do is delete the channel name an start over (or use some other available character). There is also no "Caps Lock" or similar function.  Each character must be capitalized individually.
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4  Linuxslate.com Reviews & Commentary / Review Discussions / Re: Mini Review DOLCOM GP328 PLUS and discussion
 on: Apr 22nd, 2023, 9:49am 
Started by Administrator | Post by Administrator
I in the first post of this thread, I posted to following hypothetical question:
Has this (cheap) old Cynic finally found the Chinese Radio that fits his needs?

--- and The Answer is -- Yes.  The DOLCOM GP328 PLUS is now my EDC (Every Day Carry) HT.
My HamGeek FB-8, Reviewed Here, will go into my bin of things to sell at the next Hamfest.  My Wouxun KG-UV9D Plus (See this thread about programming the Wouxun KG-UV9D Plus from a Linux PC) is a more serious, and more professional radio, but without USB charging, and given that the DOLCOM GP328 PLUS has all of the features I actually use, the Wouxun KG-UV9D Plus will probably just remain in a drawer, and eventually join the HamGeek FB-8 in my Hamfest display case.
If you are a serious Ham operator looking for your main HT, you probably aren't (should not be) looking at $40 off-brand radios.
If, however you are looking for a broad receive HT to have in your car, truck, backpack or pocket, and you may, on occasion slip off into the GMRS bands, business bands, or other places*, this radio will fit the bill -- and not a lot of bills.
It would also make a great gift or incentive for a young person to study and get their ham license.
*Operating this or any transmitting device outside of the bands you are licensed to transmit on is illegal.  Setting a radio that is not FCC approved for GMRS, FRS, or specific business bands to those frequencies, and then transmitting is also illegal regardless of license.  This radio did not come with any FCC markings, and thus could be confiscated in the United States regardless of use or non-use.  This radio must only be used by a licensed ham, and must be use responsibly.
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5  Linuxslate.com Reviews & Commentary / Review Discussions / Re: Ailunce HS2/Radioddity QR20/Q900 SDR Transceiv
 on: Apr 19th, 2023, 8:37pm 
Started by Administrator | Post by Administrator
Quick Firmware Test Results.
Note:  Check back on this page for updates as I use the FW.  I just wanted to post something quickly.
I installed the latest Firmware on the Guohe Electronics Download page as of this writing.
Link:  HW3.0&4.0 SW 3.4.0.rar.
Resulting Archive: SW3_4_0.zip
Date (as listed in the log file mentioned in the previous post): 2023.4.16

  • The Startup Screen Logo has changed.  Note that this could possibly mean that it will re-brand a radio if it is installed on a different radio, although they could still have separate startup screen files, and Guohe only changed their own (hopefully).  The new logo is professional, and not as intimidating as the old one.
  • The Factory Settings menu password is still unknown.  (Did not revert to the known one.)
  • USB KEYBOARDS WORK !! Grin.  This makes entering your Call Sign and Channel Memory names MUCH nicer.  It's worth buying a small USB keyboard just for this radio.
  • USB Mice seem to be at least partially supported. But in a quick test, I could not get the scroll wheel to tune the radio.  Perhaps I was just not in the right mode.
  • There does not seem to be any improvement in AM squelch. (Still non-functional)
  • As the 3.3.2 release notes say, Saving channels now seems to work.  Again, more use is required.
  • My listed HW Version is still 3.0.  This, along with some advertising I have seen, would seem to imply that there are now different actual Hardware versions of this radio.  It is unclear if future FW updates will continue to support older radios, and if so, for how long.

More Observation after Trying FW 3.4.0:
  • There are still problems saving and recalling Memory (Stored Channels)
    The Log for FW-V3.1.8 States: "4. Resolve channel storage data errors."
    The Log for FW-V3.3.2 States: "3. Fix the problem that the channel cannot be saved."
    Obviously they are aware issues here and they did not actually fix it in 3.1.8.
    Also, technically, they may both be true, but Channels can still not be saved and recalled properly.
    I attempt to store the local Tower Frequency (AM aircraft) in Memory (Channel) 10.
    I go to Channel 11, and then press Down to return to Channel 10.  The incorrect frequency is displayed.
    I press Down again, and go to channel 09.  I press Up to return to Channel 10.  The correct frequency is displayed.
    So obviously the frequency is stored, because by approaching Channel 10 from a lower Channel results in the proper frequency.  It is just not recalled properly when I approach Channel 10 from higher Channels
  • Even given the above, There seem to be numerous issues saving and correctly recalling Channels.
    In my numerous attempts to discover the previous note, the contents of other Saved Channels was corrupted.
    It also seems that the state of "OUT-BAND-EN" may have an effect on Channel storage.  It will not allow storage of Out of Band Channels?
    UPDATE:  After struggling with this for an hour, It does seem that I cannot store an aircraft frequency (for example) at all if OUT-BAND-EN is OFF.  In fact, Setting it to off after out of band frequencies are stored in a Channel(s), seems to result in all out-of-band stored channels being lost/overwritten.  
    Channel Storage may be better, but it is still far from fixed.
     Guohe needs to systematically examine their code, and carefully check operation.
  • When I installed the FW-V3.4.0, it erased my Call Sign, and all Stored Channels.  Especially without a way to save channels via a PC or Android App, this is unacceptable.  The full potential of this radio is only realized with the storage of many channels.  Having to program them back in again one at a time is not a reasonable request of the user.
  • I mentioned previously that USB Keyboards work.  Here are a few more notes on this:
    USB Keyboards that also contain a USB hub do not work.  In fact, I currently believe that a hub cannot be used at all.  The device plugged into the radio must directly identify itself as an USB Keyboard (or Mouse).  If follows from this that a USB Keyboard and Mouse cannot be used at the same time.
  • Most Wireless Keyboards with a dedicated receiver ("Dongle") do work.  As with a wired Keyboard, the dongle cannot be left in the radio, as the radio will not power on with it inserted.  Bluetooth wireless keyboards do not seem to work.  Even though the radio does have Bluetooth, there is no provision for pairing a device like a keyboard.
  • (UPDATE From Previous Post) If a keyboard is attached, the Power Button may have to be held for a longer time to get the radio to Power On.  
  • I am not sure if this is an update to the Radio, or to Linux, but the radio now seems to be properly detected as a USB sound source and sound sink to Linux.

NOTE:  This is a website devoted to Open Source Software.  If Guohe Electronics would release the source code for this radio under and appropriate Open Source License, the developer community could probably fix most of these issues in a day.
We would also likely have dozens of additional apps for this radio -- for example aircraft ADS-B Tracking.  Note that open source code for decoding is already available for decoding ADS-B signals.
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6  Linuxslate.com Reviews & Commentary / Review Discussions / Re: Ailunce HS2/Radioddity QR20/Q900 SDR Transceiv
 on: Apr 19th, 2023, 7:45pm 
Started by Administrator | Post by Administrator
NEW Firmwares
Again, there seem to be new firmwares on the Guohe Electronics Download page.
Version 3.1.4 dated 22 August 2022 seems to have been removed.  I have reported the fact that some (but not all) of the previous FW versions seem to disappear.
Although the link you click to get the FW files Says e.g. "HW3.0 SW 3.3.2.rar", the resulting file is actually a .zip file.  Again, the zip contains only the raw binary FW-NEW.bin file -- No release notes, instructions, etc.
There is also a Q900-FW-V3 log.rar, which in this case does result in a .rar file being downloaded.  This archive contains only a .txt file.  The contents of this log file is listed here:
Date: 2023.4.16
1. Fix the issue of insufficient frequency offset in NFM mode.
Date: 2023.3.20
1. Fix incorrect DMR call boot mode.
2. Add MPU6050 drive.
3. Fix the problem that the channel cannot be saved.
4. Add write channel function.
5. Add DMR setup menu shortcut keys
6. Support direct frequency operation and relay operation in DMR mode.
6. Increase compatibility with Hytera and Motorola interphones.
Date: February 22, 2022
1. Solve the problem of insufficient NFM mode downward adjustment system.
2. Add mouse drive, mouse can be used as encoder.
3. Increase GPS data output through serial port.
4. Resolve channel storage data errors.
Date: February 22, 2022
1. Solve the problem of insufficient NFM mode downward adjustment system.
2. Add an AFO interface to output different audio in different modes for easy access to external speakers.
Date: 2022.6.7
1. Switch Bluetooth input to headset audio, and when Bluetooth FT8 is enabled, the speaker can be turned off to play FT8 without affecting each other.
Date: 2022.5.4
1. Solve the transmission frequency offset problem.
2. Open the user calibration interface to provide frequency, voltage, and S-meter calibration.
3. Solve the problem of no sub tone in NFM mode transmission.
4. Add new local oscillator driver support. 

Note that the links refer to a HW3.0&4.0 SW 3.4.0.rar.  [Emphasis added].  As of this writing, I do not understand the reference to a HW 4.0.
Note that a previous Firmware incremented my HW version from 2.0 to 3.0, so I am assuming that one or both of the latest FW's will change the HW version to 4.0.
However, some advertising does mention different actual hardware versions.  At this time, I have no indication that HW 4.0 refers to an actual hardware change.  UPDATE: See next post.
I will try the available Firmwares, and report any significant findings.
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7  Linuxslate.com Reviews & Commentary / Review Discussions / Re: Mini Review DOLCOM GP328 PLUS and discussion
 on: Apr 16th, 2023, 12:36pm 
Started by Administrator | Post by Administrator
DOLCOM GP328 PLUS  RF Power Output Testing
Test Set-up:
DOLCOM GP328  ---->  Female SMA to Female SMA adapter ---->  Male SMA to Male SMA jumper cable ---->  60 DB SMA attenuator  ----> RF Explorer High-Z Input
RF Explorer set to appropriate band, Offset DB set to +60.
An on-line calculator is used to convert the dbm value observed on the RF Explorer to Watts.
NOTE:  Unit operating from a source of 5VDC applied to the USB-C port on the battery.  Results will be lower if the unit is just running from the battery.
NOTE:  The Advertising references "TX Power:10W/8W/5W adjustable".  The results I got did not support this advertising claim.  The User's Manual supplied with the radio states "Transmitting part -- Output Power 5-10W".
I should note that rated output power from HT's is often not attained unless the unit is operated from an external source of power.  I am not aware of a "battery eliminator" or +12VDC connection for this radio.  Also, the User's Manual states "The whole part -- Rated Voltage -- DC7.4V(battery).  If the unit is capable of running at e.g. 12VDC, higher output power may be observed.
VHF (2M Band 144MHz):
Low:	31.0 dbm  = 1.26 W
Med:	34.0 dbm  = 2.50 W
High:	36.5 dbm  = 5.00 W

VHF (1.25M Band 220Mhz ):
Low:	19.0 dbm  = 0.08 W
Med:	19.0 dbm  = 0.08 W
High:	19.0 dbm  = 0.08 W 

This isn't a typo or a cut and paste error.  I got the same low readings regardless of TX Power setting.  This essentially means that the DOLCOM GP328 does not transmit on the 220 MHz band.  I did not test all frequencies/bands, but the DOLCOM GP328 should not be expected to function as a transmitter outside of the 2M / 144MHz or 0.70M / 440Mhz ham bands.
UHF (0.70M Band 440Mhz):
Low:	29.5 dbm  = 0.89 W
Med:	32.0 dbm  = 1.58 W
High:	34.5 dbm  = 2.82 W

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8  Linuxslate.com Reviews & Commentary / Review Discussions / Mini Review DOLCOM GP328 PLUS and discussion
 on: Apr 15th, 2023, 4:40pm 
Started by Administrator | Post by Administrator
Mini Review and Discussion thread for the Dolcom GP328 PLUS - Another low-priced Ham Radio HT (Handheld Transceiver - Walkie-Talkie)

Has this (cheap) old Cynic finally found the Chinese Radio that fits his needs?  I'll update this later, but for now, here's a quick list of Pros and Cons:
  • Inexpensive.  Mine was just over US$40 including sales tax
  • AM aircraft receive actually works, and it seems to have a real AM mode (not just tuning the frequency and letting the FM detector try to sort out AM.)
  • Color LCD display -- It reminds me of a vtech toy, but it is readable in every condition unless you are in direct sunlight, and really try to get it to wash out.
  • The colors also actually mean something -- to a limited extent.
  • It has the typical Channel, Channel name, and Frequency modes, but the frequency is always displayed at the bottom so that you know what frequency you are actually on.
  • I was able to quickly enter the local repeater, and hit it easily with the included wip, and on "Med" power.
  • True full coverage Receive from 65 to 620MHz, and broad transmit outside of the Ham Bands (albeit at much reduced power)
  • USB-C charging.
  • It has basic scanning capabilities for both a simple frequency scan, or a scan through the programmed channels.
  • Your friends that just learned about a certain other more common Chinese radio are going to be quite jealous of your DOLCOM.

  • Feels very cheap and light (including the battery), but that's not to say that I don't think it won't survive general HT use.
  • S-meter is essentially "fake".  It simply shows presence of a signal.  It does light up half way when power is set to Medium, and you key, but it's just a hard coded half indication, it is not measuring actual power.
  • Menus are pretty basic.  The essential functions are there, but not much more.
  • More research is needed, but as of right now, it does not seem that you can use a PC (with either proprietary SW, or CHIRP) to program frequencies.
  • The Headphones and Mic connectors are much closer together than other common radios.  Headsets, Speaker/Mics, etc. for other radios won't work unless they have separate (not molded together) plugs.  Of course this would include programming cables if the radio supports programming via these connectors.
  • There's a white LED flashlight on the bottom. If the flashlight button is pressed again, small red and blue LEDs illuminate, but the white LED remains on, totally overpowering the red and blue LED's.  Another press makes all 3 flash, but again it just appears white at any distance.  I'm not sure what the intent here was, but it is just another aspect that makes this radio appear like a toy.

Please check back soon. I will update this post with actual power output measurements, and other info about this radio.
If you would like to ask a question or if you have this radio, please register email "john" at this domain.  This domain is "linuxslate.com".  I will manually create an account for you.
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9  Original Projects and Builds / Other Builds and Projects / Re: Poor Man's version of the Monster GO DJ
 on: Apr 10th, 2023, 3:01pm 
Started by Administrator | Post by Administrator
So I keep learning about other similar products.
In addition to the 2 Technical Pro Products described here, I have discovered a number of others.
What I will describe here are all similar in at least the basic form factor.  They are rack mountable Dual MP3 players/mixers.  As far as I know of this writing, they all fit in a 3U rack space, but are also designed to be operated just laying flat on a table.  They are likely intended as a "drop-in replacement" for the control head of older Dual CD Players, but of course not needing the separate (also rack mount) Dual CD Player (Drives).
It's not my intention to single out a particular product, but I am going to use the PYLE-PRO PDJ480UM as most typical of these products.  It is pictured here:

                                                              PYLE-PRO PDJ480UM  Photo from Pyle Website
The same product (although unbranded) seems to be available from Chinese manufactures/vendors listed simply as "DJ Controller, Supports USB and SD Card Player".  I have also seen what appears to be the same product branded as the "UC3".
Numark DDS
This one appears slightly more elegant than the other products mentioned here.  It has a single Color display in the center.
Pyle-Pro PDJ450U Pro DJ Media Player Controller
Another Pyle branded product, and like the Numark DDS, it has a single screen in the center.
The same product seems to be sold as the T&W International Audio Co.,Ltd SDJ-1000US  as well as possibly other identities via  various Chinese Vendors.
The next several products seem to be the same device with different cosmetics and branding:
American Audio SDJ2  
JB USB 900  (JBSystems)
Citronic MPSD-2
UD999 (Unbranded)
The UD966 (Also Unbranded) seems similar.
Another one is the American Audio SDJ1 / SKP Pro Audio USD-2010 /  DJ Tech S1.  The same device may also appear with additional names/branding.
Note that these devices are just dual players with separate outputs.  They do not have mixers, faders, tone controls or Mic inputs.  I am leaving them on this list because they are similar devices.
Note that this list only contains self-contained units that do not include or attach to CD players.  Many Dual CD players/controllers will play MP3 files burned on to a CD.  This list would be much longer if I added those.  (Note reference to my Numark Mix Deck Express referenced earlier in this thread.  I also have a Gemini Dual CD player with remote head.)  
It is very possible that all of the devices listed on this page are obsolete, although some seem to be available.
Note that none of these devices seem to have nearly the sophistication of the Go DJ / Go DJ Plus, such as the spinning record animation or waveform displays.
None of these devices are portable/battery powered.
Note also that newer, high end devices, such as the Denon DJ Prime Go are not on this list.  I consider them to be in "Their own class" (and I'm sure Denon would not want the DJ Prime Go on a list with $150 obsolete products). The Denon DJ Prime Go was mentioned early in the thread.
If you have any additional information about the devices mentioned here, or other similar Dual USB/SD players, please email "John" at this domain, and request registration.
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10  Original Projects and Builds / Other Builds and Projects / Re: Malachite DSP - SDR  Radio Receiver
 on: Apr 6th, 2023, 10:00am 
Started by Administrator | Post by Administrator
New Firmware and other updates to my Malachite DSP - SDR  Radio Receiver
1.  Firmware FW_1_10d.d
2.  Battery Issues
As mentioned previously, It seems Firmware Development for this radio has slowed or stopped.  If one follows the links provided in previous posts, and clicks on the "Прошивки(FIRMWARE)", one will end up getting only a text file.  This text file contains a link to a Google Drive location, and in that location, one will find a file "Malahit_FW_1_10d.rar" (Not FW_1_10c) and an update Change Log.  Inside the RAR file is only the file Malahit_FW_1_10d.hex.
Being the brave soul that I am -- and willing to risk my radio for all users everywhere, I downloaded and installed this Malahit_FW_1_10d.
What did I do specifically?  (Detailed instructions) -- Assumes Linux, but should be similar on other platforms:
  • Follow the maze of links and Yandex and Google Drive directories until you have a local copy of Malahit_FW_1_10d.rar
    Here is a link to the relevant Google Drive as of the date of this post: https://drive.google.com/drive/u/1/folders/1OSoUMOVRloHKc-OYGKLIlNRtheimGgPV . Note that I am not responsible for the link or it's contents.
  • Right click on Malahit_FW_1_10d.rar, and select Extract Here.  This will result in a single file Malahit_FW_1_10d.hex
  • Since I have been successful in the past flashing DFU formatted firmwares, I converted Malahit_FW_1_10d.hex to DFU format.  This is optional if you have a reliable way to flash .hex files.
  • To convert the file to DFU format, I used the Windows version of the official STM DfuFileManager (part of DfuSe v3.0.6).
  • Put the radio in DFU mode by 1.) Turning the Radio off.  2.) Press and hold the Volume (top) encoder wheel.  3.)Press the On (Standy/Wake) button.
  • The Radio screen will be off (No display).
  • Connect the Radio to the PC with an USB A-to-C cable.
  • Verify the radio is in DFU mode with the command
         dfu-util -l
    You should see one or 2 lines with something like:
    Found DFU: [0483:df11] ver=0200, devnum=8, cfg=1, intf=0, path="1-1.6", alt=1, name="@Option Bytes   /0x5200201C/01*128 e", serial="xxxxxxxxxxxx"
    Note that the path, and serial number will be specific to what USB port you use, and your specific radio.
  • Flash the firmware with  
    dfu-util -a 0 -i 0 -D Downloads/Malahit_FW_1_10d.dfu'
    Note that the path must be correct for the location of your firmware file.
  • dfu-util will show the progress of the load.  There should be 3 separate sections sent, with only the middle one taking any significant time.
  • Don't worry about a 4th segment, and a message about "Not Writable".  This message is normal.
  • Disconnect power from the Radio (This is much easier if you have a battery disconnect switch -- See previous posts about getting the radio out of DFU mode.)
  • Power up the radio. You should see the newer, more colorful start up screen, and it should display 1.10d in the lower right.

I'll post comments on this latest (last?) firmware after I have had more time with it.
Battery Issues
I had another problem with my Malachite DSP - SDR  Radio Receiver.
These radios drain the battery over time unless the radio has a hardware battery disconnect switch.  The drain is much worse on the "Test" or Unregistered firmwares, but it is present on all FW versions.  Over time, this will drain the battery, and there is no low voltage cut-off.  Draining a Lithium Ion/Lithium Polymer battery below ~3.3VDC is very bad for the battery, and possibly dangerous.
I noticed that my Malachite DSP - SDR  Radio was not holding a charge very well at all.  I opened the case, and was amazed to find a VERY puffed battery.
There is also the possibility that these radios (at least the Chinese clones) are over charging the batteries or charging them at too high a rate.
I replaced the battery (4000mah) with a 8000mah battery.  Note that at a given charge rate specification (e.g. "1C"), an 8000mah battery can be charged at twice the current of a 4000mah.  So in general, a lager capacity battery is going to be more tolerant of "hard" charging than a smaller battery.
  • As with everything - Never charge a LiPo battery unattended.
  • Encased, Round cells (e.g. 18650) are safer than bare rectangular cells, but check all LiPo batteries for leakage/dimensional changes or heating periodically.
  • Install a battery cut-off switch if your Malachite DSP does not have one.
  • Remember to use the cut-off switch (turn it OFF) if the radio is not used for any period of time (even a few days).
  • If building your own (or modifying) one of these radios, use high capacity, good quality cells.

I would also like to note that a very similar battery arrangement in My "Poor Man's Go DJ" has not puffed at all despite being subject to a much higher load, and much more frequent use.  This is what leads me to believe that the Malachite DSP - SDR  Radio is charging the battery in a way that is not good for it.  
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