Mini review: 3 speaker microphones

One would expect that making a simple but quality speaker-microphone is one of the easiest things to do. Yet complaints about this accessory are common: bad PTT keys, TX audio sub par, unreliable wiring — and the list goes on.

I acquired three commonly sold models: a generic, brand-less one, an original Wouxun and the latest offering from Baofeng. Below a picture of the three microhpones in the same order.


Generic, brandless
Pro: cheap, reasonably good loudspeaker, but with a tendency to resonate.
Cons: Nasal TX audio (both highs and lows mostly absent).

Pro: nice form factor (larger, more comfortable to hold), reasonably good loudspeaker, quality PTT key.
Cons: muffled TX audio, making the conversation hard to understand.

Pro: cheap, very good loudspeker, excellent TX audio, quality PTT key, shielding at the back.
Cons: wiring a bit stiffer than the competition.

Winner on almost all counts: Baofeng. Warning: this microphone has already been copied. The copy is recognizable by the lack of the metal shielding / mounting plate at the back. A picture of the original below:

OLYMPUS DIGITAL CAMERAPrice: $ 7.79 (€ 5.63) on eBay. Link to seller I got this one from:

Puxing PX-780 DMR Radio

Puxing jumped the bandwagon too and introduces the Puxing PX-780/PX-820 DMR Tier II radio. Prices unknown at this time; you have to mail them through for more information.

PuxingThe radio is available in both VHF and UHF versions. GPS appears to be a standard feature.


General Specifications
Frequency Range 136-174MHz /400-470MHz /customized
Channel Capacity 1000/customized
antenna impedance 50Ω
Operating Voltage 7.4V  DC
Operating Temperature -30°C +60°C
store temperature -40°C +85°C
Battery Life in 5/5/90 operating mode
1700mAh standard Li-ion battery analog:10hours,digital:14hours
dust-protection and water resistant IP67
Size not including antenna 113.5mm×54mm×33.5mm
Weight with battery, antenna 270G
channel spacing 12.5khz
frequency stability +/-1ppm
Output Power low power:1W high power:4w
hum and noise -40dB@12.5khz
conducted,radiated spurious emission -36dBm@ <1Ghz,-30dBm@>1Ghz
adjacent channel power -60dB @12.5khz
ajacent transient channel power -50dB@ 12.5KHZ
FM modulation mode 12.5khz:11K0F3E
4FSK digital mode 12.5khz(data only):7K60FXD 12.5khz(data+voice):7K60FXE
modulation maximum deviation 2.5khz@12.5khz
nonactive slot power -57dBm
audio response +1dB–3dB
audio distortion 3%(type)
digital protocol ETSI TS 102 361-1,-2,-3
vocoder type AMBE+2TM
channel spacing 12.5khz
frequency stability +/-1ppm
analog sensitivity 0.35μV/-116dBm(20dB SINAD)0.22μV/-120dBm(type)
digital sensitivity 0.3μV/-117.4dBm(BER 5%)0.7μV/-110dBm(BER1%)
intermodulation TIA603C:70dB ETSI:65dB
Adjacent Channel Selectivity TIA603C:65dB@12.5khz ETSI:60dB@12.5khz
co-channel rejection 12dB@12.5KHZ
spurious response rejection TIA603C:75dB ETSI:70dB
conducted spurious emission -57dBm@<1GHz,-47dBm@>1GHz
blocking 84dB
rated audio power 1w
audio response +1dB–3dB
rated audio distortion 3%(type)

Muddying the waters: Pofung


BF-9500Pofung? A new name, but don’t expect anything interesting to happen. From what I could find all Pofung radios are identical to the ones we already know. The name was spotted by Craig N7LB on the Baofeng website.

What Baofeng can do now – and already does – is re-branding products from other manufacturers. One of these products is a mono-band mobile transceiver we all know to be manufactured by Anytone, the AT-588.

In my opinion all of this is only muddying the waters even further, which is the last thing we want.

Dutch hams: “Goodbye XP, Hello Linux”

I never wanted to be a Linux evangelist, and never pretended to be one either. Times change. Microsoft’s end-of life announcement left many hams using Windows XP worried. What to do? Do what more and more ham operators are doing here: switch to Linux. It’s fast, beautiful, safe and (here comes the magic word) FREE.

Best of both worlds
Dumping XP completely in favor of Linux might not be a good option for everyone. Some ham related software can’t do without Windows. What you can do then is install Linux next to Windows, a so-called dual-boot system. Boot Linux for safety, speed and the wealth of more than 62.000 applications, and boot XP when you really have to.

What Linux version?
Linux addicts like to live on the bleeding edge and switch from version to version. Most popular versions (called distributions, for a list see have a life cycle of 6 months or so, after which you’re supposed to update to the new version. I agree that this is fun, but for the average user this is not very practical. A smarter option is to pick an LTS (Long Time Support) version, which is supported for a period of 5 years. Ubuntu and Mint (which is based on Ubuntu) both offer such LTS versions.

Not too long ago Ubuntu had everything going for it, but that changed from the moment the developers tried to force-feed Unity, a new graphical user interface, to their users. I’ve worked wit Unity – at least I tried to – but found it to be mediocre at best. Linux Mint on the other hand lets you pick the desktop environment of choice. As a result the popularity of Ubuntu dropped like a stone, while Mint’s user base exploded.

The most popular desktops are MATE and Cinnamon. Both are slick, fast and ideal for Windows users who love a start button of sorts and navigate through applications the way they used to. Below screenshots of MATE and Cinnamon.

The current LTS version of Linux Mint is version 13 (Maya) (download here) which will be supported until mid 2017. Make sure you pick a version suitable for your system — you need to know if your processor is 32-bits or 64-bits. A new LTS version of Mint will be available around June 2014.

If you give Linux Mint a try, please report back to me. I’d love to hear your comments and will do my best to answer any questions you might have.