Further testing on the cassette port, recording and playing back from a PC.
The cortex connected to the MIC IN on the PC and the LINE OUT
I found i needed the record and playback volume at max.
Also, mute all mixer channels on the recorder and playback mixers except for the Wave out and the Mic in.
I found i was getting noise from the CD channel even with it's volume slider at zero, went away when muted.
The cassette interface test program in the build manual is very useful for checking the PC output level is ok and that there isn't spurious noise on the signal.
Look at pin 3 on IC67 with a scope while playing back the wav.
I've uploaded 3 wavs to my web site, are these the first Cortex programs on the net ?
http://www.quantums.info/cortex/cortex tape test.zip
This is 30 seconds of output from the cassette interface test program, alternate 0.5 second bursts of 1's and 0's
http://www.quantums.info/cortex/cortex CAS_TEST.zip
This is the program above, as per the build manual.
http://www.quantums.info/cortex/cortex C_BARS.zip
This is the program for generating the colour bars for setting up the video, again, from the build manual.
Jim