CHIRP

please try the opensource pl2303 driver:

http://1drv.ms/Nl68Ru
At this web page you may need to right-click or control-click to link to get it to download. After downloading, you may need to control-right click, then open in order to bypass Mac Gatekeeper.

Tried to use that driver but it wont load in Yosemite as the kext is incorrectly signed.

Tim Kerby wrote:

Tried to use that driver but it wont load in Yosemite as the kext is incorrectly signed.

I had similar freeze issues with a "genuine" Prolific cable as well, when using Chirp on my Mac OS X (and also on Windows 8) with my Wouxun KG-UV8D, although there was no problem with the same cable with Kenwood TM-V71A or Baofeng UV82. I tried different drivers, prayed to different deities and demigods :-), and finally just broke down and bought an FTDI cable at amazon.com http://amzn.com/B0097E2I2S

Everything has been perfect with the FTDI cable. I wish I had spent this $20 earlier, rather than trying to save a couple of bucks on a cheap prolific cable.

unfortunately with yosemite, drivers (i.e., kexts) have to be signed.
This is a problem affecting much more than just Chirp and serial chipset drivers.
If you want to sign your drivers, you have to pay apple 100 bucks to get a developer cert - and this is not going to happen for most open-source, hobby-grade projects.

The other option is to disable kext signature checking system wide (which is a very big hammer for such a small nail).
which is using boot-args kext-dev-mode=1 as seen http://www.cindori.org/trim-enabler-and-yosemite/

This is obviously not a desired solution from a security standpoint, but appears to be the only workaround.

Hoping that Apple will get lots of flak for this and implement an easier way, such as allowing user to selectively whitelist specific modules.

Unfortunately, with recent stunts that FTDI has pulled, it has become obvious that there are probably alot of fake FTDI chips out there (similar situation to prolific).
So your cable might work for now on Mac (at least until FTDI convinces Apple to use their "we-disabled-your-counterfeit-ftdi-chip-for-you" code in future apple ftdi drivers). But you will still be out-of-luck on windows.
One would be hopeful that this forces cable manufacturers to use genuine chipsets, however if anyone is in tune with the reality of global supply chain and fabrication situations (i.e., follow eevblog, etc) you will probably not be so hopeful. Especially so for cable market absolutely dominated by chinese clones.