Here are instructions for testing IC Tester device and cable.

On picture above is silkscreen layer with position of elements on board.
You can help with it in next testing, with brown color is marked copper lines which are on top side (components side) and with green color copper lines from bottom side.
After soldering, we need to check if everything is properly soldered.
For that purpose, remove all ICs from sockets, then you'll need multimeter or something else to test if wire or copper line on board is whole or it's broke.
We don't need perform full check right now, only basic will do, follow this steps:

1. Check connections from SOC1 and IC1 socket. Check that each pin on SOC1 socket is connected with ONLY ONE pin at IC1 socket and not with any other pin at SOC1. If it's connected with more pins or none you need to resolder that it have only one connection.
2. Now check on same principle connections between IC1 socket and CONN1.
3. Next we must check inputs, test if copper line which connects R1 and CONN1 connects on IC2 to IC5 sockets ONLY pin 3 at each socket. If there are more connections or none on some socket you need to resolder that it have only connection at pin 3.
4. Test if copper line which connects R2 and CONN1 connects on IC2 to IC5 sockets ONLY pin 1 at each socket. If there are more connections or none on some socket you need to resolder that it have only connection at pin 1.
5. Test copper line which connects R3 and CONN1, which connects ONLY pin 2 at IC2 socket. Next test connection between pin 9 at IC2 socket and pin 2 at IC3 socket. In that case pin 9 on IC3 socket with pin 2 on IC4 socket and pin 9 on IC4 socket with pin 2 on IC5 socket. If there is a more or none connection at sockets you need to resolder them.
6. Now check that there are ONLY connections between pin 9 at IC5 socket with R47 and R47 to pin 12 on CONN1.
7. Found copper line which connects CONN1 and pin 15 at IC5 socket. Make sure that it connects ONLY pin 15 at IC2 thru IC5 sockets and LED1, otherwise you need to resolder that.
8. Check that GND copper lines connect on IC1 socket ONLY pins 9 and 12. On IC2 thru IC5 sockets ONLY pins 8, if not resolder sockets.
9. Test cable, in way that each wire isn't connected with any other wire.
10. Connect cable to device, and make power up. Checks that are both LED4 and LED5 lighted. If isn't, check for CONN2 and/or input 3,5 mm stereo connector for correct soldering.
11. Now check that there is power of +5.5 volts or higher at left side of IC6 (CONN2 side). If not, check D2, D3 and CONN2 if properly soldered or correctness of D2 and D3.
12. Check that +5 volts power are ONLY at pin 24 on IC1 socket and at pins 16 on IC2 thru IC5 sockets. If not resolder sockets.

O.K. That's it. Now we finish basic testing at device and cable. Detach cable from device and place ICs at their sockets.
Now start ictester program with option -t, eq: ictester -t and follow instructions.

Here are in details explained all phases of that testing:

1. Port functionality
   • Remove all hardware devices which may disrupt testing port, you can leave hardware devices if they aren't powered and if in that state do not respond to communications from port or obstruct it.
   • If connected, disconnect ictester device from port, you may leave cable in parallel port as disconnected from ictester device. In that way you can test cable again.
   • Close or stop all programs that may use port, if program uses port but don't obstruct data transfer you can leave it, but safe is to terminate.
   Now you can press enter key and test port. If error occurs, it will be one of those:
   • Testing port port_no failed.
     Can't get response from port, it may be blocked from other device or program.
     There's problem in communication with port, possible hardware for that port don't exists or not working properly. There can be also problem in drivers which working with that port.
   • Testing port port_no failed.
     Got answer from port during test phase.
     It's possible that some other hardware device respond or some software disrupt data transfer.
     It's possible that there's some hardware attached at port, of course some program can obstruct testing port too.
     So remove all hardware from port and close all software which may use it and repeat test.

   If there's still error then something is wrong with port, try to use another port.

2. Test device connection
   • DO NOT CONNECT POWER ON ICTESTER DEVICE!!!!, remove external power supply and
   • connect ictester device to port, put cable to parallel port and to IC Tester device, of course WITHOUT EXTERNAL POWER !
   Now you can press enter key and do test. If error occurs, it will be one of those:
   • Test fail, not found device.
     Respond from device not detected, follow next steps:
     • check if ictester device is connected to right port
     • check if all wires on DB 25 connector are properly soldered
     • check if all wires on DB 15 connector are properly connected

   If there's still error then recheck integrity of all copper lines at IC Tester on CONN1.

3. Test device power up
   • now connect power to ictester device

   When you connected power, LED2, LED4 and LED 5 (yellow led diodes) will light up.

   Now you can press enter key and do test. If error occur, it will be one of those:
   • Test fail, not found respond from device.
     There isn't confirmation from device that there's power present, to solve problem follow next steps:
     • check if you are properly connected power to ictester device
     • check if any power coming to ictester device
     • check if input power is 6V or up to 9V, possible low input power
     • check that IC6 - 5 volt regulator working properly

   If there's still error then, if you fix the problem, send me email and wrote what was the problem and how you fix it.
   You can not fix the problem? No, that's not the option, FIX IT!!!

4. Test read on device
   

   You will need piece of wire for this test.

   • remove from test socket any IC or other part that may be in it
   • use wire for connecting GND (one of sides of CONN3) and pins at test socket
   Follow instructions provided by the program. If error occurs, it will be one of those:
   • Error on pin pin_no, it's possible that pin pin_no and pin pin_no are connected together.
   • Error on pin pin_no, pin not connected to GND?
     You must connect with wire requested pin on test socket and GND, you connect wrong pin, aren't you?
     To solve problems follow next steps:
     • check leads on ictester board which connects IC1 socket and SOC1 if they correctly soldered
     • check if IC1 socket is correctly soldered and IC1 correctly connected
     • check if all copper leads to CONN1 are properly soldered

   If there's still error then problem could be in cable or in IC1, recheck again if they working properly.

5. Test write on device
   After we tested IC1 and reading from test socket SOC1, now we'll test setting GND on test socket.
   • remove from test socket any IC, wire or other part
   Now you can press enter key and do test. If error occur, it will be one of those:
   • Test fail, setting data on device fail during set pin_no pin.
     To solve problems follow next steps:
     • check ICs from IC2 to IC5, if they connected and working properly
     • check leads on ictester board if they correctly soldered and connected from IC2 to IC5 sockets.
     • check if all copper leads to CONN1 are properly soldered
   • Test fail, there are some errors at tested pin pin_no.
     Program will tell you which leads and parts you must check on ictester board.
   • Test fail, there are some errors at pin pin_no.
     There's error at some other pin at SOC1, program will tell you which leads and parts you must check on ictester board.
     When you got which parts may be involved in error, do following steps:
     • check transistors, if they connected and working properly
     • check resistors, if they connected and working properly to transistors
     • check IC, if it's connected and working properly to resistors
     • check leads on ictester board if they correctly soldered and connected

   If there's still error recheck if IC2, IC3, IC4 and IC5 working properly.

6. Test active write on device
   You will need resistor of 560 to 1000 ohms for this test.
   • remove from test socket any IC or other part that may be in it
   • use resistor for connecting two pins at test socket
   Follow instructions provided by the program. If error occur, it will be one of those:
   • Test fail, setting data on device fail during set pin_no pin.
     To solve problems follow next steps:
     • check ICs from IC2 to IC5, if they connected and working properly
     • check leads on ictester board if they correctly soldered and connected from IC2 to IC5 sockets.
     • check if all copper leads to CONN1 are properly soldered
   • Test fail, resistor which connects pin pin_no and pin_no is too strong.
     This resistor which you use is too resistant for this testing, use resistor with fewer ohms.
   • Test fail, resistor which connects pin pin_no and pin_no is too weak.
     Resistor which you use, is not enough resistant for this testing, use resistor with more ohms.
   • Test fail, there are some errors at pin pin_no.
     Program will tell you which leads and parts you must check on ictester board.
     When you got which parts may be involved in error, do following steps:
     • check transistors, if they connected and working properly
     • check resistors, if they connected and working properly to transistors
     • check IC, if it's connected and working properly to resistors
     • check leads on ictester board if they correctly soldered and connected

   If there's still error recheck if IC2, IC3, IC4 and IC5 working properly.

7. Test read/write on device
   On last test we tested how ictester sets +5 volts, now we will perform setting GND and +5 volts simultaneously.
   • remove from test socket any IC or other part that may be in it
   Now you can press enter key and do test. If error occur, it will be one of those:
   • Test fail, setting data on device fail during set pin_no pin.
     To solve problems follow next steps:
     • check ICs from IC2 to IC5, if they connected and working properly
     • check leads on ictester board if they correctly soldered and connected from IC2 to IC5 sockets.
     • check if all copper leads to CONN1 are properly soldered
   • Test fail, there are some errors at pin pin_no.
     Check which transistors and resistors are connected with pin_no and:
     • check transistors, if they connected and working properly
     • check resistors, if they connected and working properly to transistors
     • check leads on ictester board if they correctly soldered and connected

   If there's still error, it's possible that input data are corrupted, recheck cable and try to close all programs that may use this port.

If all tests went O.K., testing is complete, you can safely use IC Tester device for testing ICs.
You can now read Program - ictester section to find other options, which are available from program and how to use it.