As can be seen at the first schematic posted
http://www.8052.com/forum/read/166434
the circuit has typical configuration:
a. oscilator by the crystal Y1
b. Reset by RC circuit
c. EA is strapped to Vcc for internal program execution
d. Vcc is filtered by a 0.1uF cap
OK

Comments:
1. There is no service level options like a button and a led.
2. Try to add a button and a Led for testing purposes.

Suggestions:
I suggest this should be the first step to make the circuit alive.
When the service level options are working
then try the serial communitations over RS232C.

Serial Comms:
Depending on the crystal you choose should be the options about
the desired transfer rate between the PC and the target board.
The serial protocol devices are classified as DTEs or DCEs.
Data Terminal Equipment (like PCs ...)
Data Communication Equipment (like Modems ...)
The connection between devices may have many options on the
cable wiring as straight cables (DTE to DCE),
or crossover cables (DTE to DTE) like "Null Modem Cable".
Take a look at this
http://www.bb-elec.com/bb-elec/literature/tech/faq_rs232_connections_work.pdf
You should decide how to classify this board and use the correct connections.

Try a step by step approach and you will overcome the issue.

K.L.Angelis