Hi,
This is a project I am currently into. I am passing the
information so it gets recorded somewhere for others, and also
because I have a few information requests.
I have a FT-757GX from the 80s. I just cannot afford what a newer
HF costs. Also I got to like this one :)
It has a very primitive CAT interface, which can be used only to
command the radio. (Change VFOs, Frequency, enable/disable functions)
Unfortunately:
1- It cannot change the mode (a rotary switch)
2- It cannot report information back (the CAT is
unidirectional)
3- As a consequence of 2 if you make a change in the front
panel, it goes completely unnoticed
So, I am building a USB CAT control, quite enhanced, and
bidirectional.
I intercepted the relevant display unit signals, and I am already
decoding all the information on the display.
I intercepted the DC levels of Shift and Width, so a DAC can
provide them, and an ADC can read the potentiometer
I am reading the Forward Power, Reverse Power, AGC, and ALC
I can write serially to the original CAT, to setup anything (but
most importantly the frequency)
I can PPT from the CAT
That is a LOT more than the original.
Identifying the signals, and getting shielded wires out of the box
took about 3 hours. That isn't much it was easy because all of them
were tapped at connectors instead of the PCB.
It took me about 2 hours more to decode the display unit signals.
It took me more time to work out all the details for the firmware,
particullarly the USB part, and the UART part. Curiously the part
were I intercepted and decoded the signals from the display unit,
which was made using interrupts, worked flawlessly from the first
try, I could not believe that!!
I already have a working hardware design arround the PIC18F4550,
with working firmware arround the Microchip CDC USB driver which
emulates a COM port.
More information if wished:
http://www.albinarrate.com/index.php?
option=com_content&task=view&id=12&Itemid=30
So right now, I have to decide what to do with the commands...
This is the part were I need help...
I intend to emulate a more modern transceiver, with standard text
commands (I want to be able to control it from Hiperterminal to
access non standard features), not like the old Yaesu CATs.
So I have to decide WHICH model to emulate....
It should be one available at least in Ham Radio Deluxe, and MixW.
Something like FT2000, TS850 or TS870
All ICOMs have binary commands right? That leaves them out...
Any opinions on this? What would be the best choice?
73 for everybody!
Javier LU8AJA
