The USB cable is a direct cable with a USB connection on one end, and the 3.5 mm 4 conductor plug that is normally speaker mic, but used to clone. Nothing in between. It was purchased specifically for the VX-3.
There *should* be something in between. The radio does not speak USB, which means you need a USB-to-serial chip in between. This is normally hidden inside the USB hood, since it's so small. If you didn't have anything, then you wouldn't see a new serial port show up when you plug it in.
Given the discussion below, I really think it's a combination of potentially one bad cable and maybe a not-fully-seated second cable. If you don't get the clone header in HyperTerminal, then something's just plain not connected.
The "real serial cable" comes from the 9 pin D connector to a 3.5 mm regular stereo connector (3 conductors including ground), that then goes thru an adapter to the 3.5 mm 4 conductor plug used for cloning. Years ago, this worked fine this way with a VX-5, so I doubt it has changed, unless the VX-3 and VX-5 have the TxD and RxD switched.
Yep, agreed, although I'd suspect any and all of that as being the problem, either preventing physical insertion, or not connecting the proper pins.
At this point, I am thinking that possibly the plastic around the jack on the VX-3s do not permit the cable to go all of the way in. It looks like it goes in all of the way, but it is really up against the plastic case, so it is hard to tell for sure. And no way to really test that. Of course if it was not in all of the way, the TxD and RxD connections would not be the right place, and it would not work.
Yep, this is why I asked about fully seating the connector. Sounds like there may still be some work to be done here.
Of course one would hope that a cable bought specifically for the VX-3 would fit the VX-3!
Where did you get it? There are tons of devices that use 3 and 4 conductor TRS connectors for cloning and I wouldn't put it past many of the ebayers to have sent you the wrong cable.
If you have the ability to check that the pins are properly connected, that might be a good next step. The pinout is:
http://www.kc8unj.com/pinout.jpg