I was so happy with my pair of Baofeng UV-B6 that I decided to buy four more to entirely replace my fleet of even cheaper Lidl Silvercrest TwinTalker PMR transceivers whose horrendous attrition hints about excessive cheapness.

Alas, as I was using the beloved CHIRP to load them with the family’s standard configuration, I encountered the dreaded ‘Radio did not Ack Programming Mode‘ error.

I was using the USB serial adapter with ID 067b:2303 “Prolific Technology, Inc. PL2303 Serial Port” with of course the Baofeng/Kenwood/etc. specific twin 2.5mm/3.5mm plug.

Some of those Baofeng UV-B6 worked fine with this cable – those are UV-B6 with 29 menu entries (with serial numbers 10B6014828 and 10B6014839)

But others were entirely recalcitrant, with a consistent error pattern – those are UV-B6 with 27 menu entries (with serial numbers 10B6025976, 10B6025999, 10B6026018 and 10B6026047).

As suggested by Miklor I slightly trimmed the plug with a cutter – no change.

I also used a couple of male/female extension cords (2.5mm and 3.5mm) in case the lack of twin plastic molding would provide unimpeded contact – no change either.

I bought two different other cables – they both turned out to also be PL2303 serial adapters with same USB ID (but with different plastic moldings – and of course different commercial names). Still no change – same frustrating results.

My last hope was to get this cable, which turned out having USB ID 0403:6001 “Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC”. The ‘Genuine‘ qualifier in its name and the photocopied sheet that attempted to pass for documentation by merely pointing to Miklor were par for the course and did not inspire me to expect anything different… But actually – it worked ! This is the legendary ‘FTDI’ cable I was reading about, the real thing, the one that works with all Baofeng UV-B6 sub-models. Was I not a militant atheist, I would certainly consider this as a proof of God’s greatness – الله أكبر and all those sorts of things !

TL;DR :
– Cables with a FTDI chip work with both 27 and 29 menu entries UV-B6 submodels
– Cables with a PL2303 chip only work with 29 menu entries UV-B6

There is still a non-zero probability that all the PL2303 chips I went through were counterfeit and that only the FTDI model was genuine – thus voiding my analysis. But with a sample of three PL2303-based cables from three different vendors, that probability is low enough for me to publish this article. A driver issue is not entirely impossible either – I have only tested with Linux, where both PL2303 and FTDI drivers are part of the standard kernel.

By the way, how does one manage a mixed fleet of 27 and 29 menu entries UV-B6 submodels with CHIRP ? Well – easy:

– If you upload an image originaly downloaded from a 29 menu entries submodel to a 27 menu entries submodel, CHIRP will give you the following error message: “An error has occurred – Radio NAK’d block at address 0x0f10” but you can disregard this message as it only concerns the non-existent menu items – the rest of the configuration has been perfectly transmitted.

– If you you upload an image originaly downloaded from a 27 menu entries submodel to a 29 menu entries submodel, no error occurs – but companding will be disabled. No problem.

Now I would be grateful if someone could explain the interoperability of the companding feature – is it still useful if it is active in only one of the two transceivers involved in a given transmission ?

Uhhh… Anyone wants three PL2303-based cables ? I’ll sell them real cheap !

Edit: also used the FTDI cable successfully with the Pofung UV-B5.