I'm informed that the original VPL-1 was a 3 part lead with the 9 pin connector and electrics terminating at a DIN socket and 2 short leads with a corresponding DIN plug and the "end" for the radio (2 different). I believe that the part with the electronics was also known as the original CT-29 (not to be confused with the CT-29A/B/F etc. offered by third parties, the original CT-29 interface was terminated with a DIN plug and a further lead was used for the interface to radio connection).
The sender of the information does not , and neither do I, have the pin assignments or DIN plug type information as yet but if I get the info I will update this page. For the moment we'll show a 5 pin DIN as these are common and you may have several spare in your "junk box", thus keeping costs down.
For the construction you can use strip board, dead bug method or even produce your own PCB if you like. Just follow the schematic. Component layout is not really critical for this circuit, although beginners (and the more experienced) may have to double check polarity / orientation of components.
Once made up check your soldering for bridged connections and wires for stray whiskers. If your construction is small enough it may fit in the shroud of the 9 pin D socket, if not a small box with short leads connecting to the 9 pin socket will work just as well.
The DIN socket (J2) should be mounted on a lead that is not too long (signal losses) but long enough to be easy to use, a metre or so should be fine, the other leads only need to be about 15cm long
Don't forget to slide the plug casings (where required) on the cables before soldering the plugs on.
To use the interface with your radio you will need the software relevant to your radio and the correct interface to radio lead (see Projects Home - Data Transfer- Yaesu for various leads).
The software is usually purchased from the manufacturer but there are sites offering downloads of both the original and third parties, the choice is yours.
Follow the instructions in your manual / software instructions or help file for connecting and data transfer.
I was also asked to modify this circuit to use it on a PC with a USB port and no serial port.
Short of purchasing or building a USB to Serial adaptor or purchasing the FIF-10A USB Interface and the relevant radio connection cable (shown as the USB option for some of the radios that use the VPL-1) from Yaesu I have no other remedy.
A USB to Serial adaptor may work but as I do not have a radio that uses the VPL-1 I cannot try it.