About three years ago I acquired a pair of Amstrad CPC464s. One I sold on to help pay for the initial outlay on the bundle (which also included my Plus/4) but I kept the other as it wasn't in the greatest condition and I had, to be honest, never owned a CPC before.
|Clear the decks! It's huge!|
As part of my escapades with the CPC, I added an audio in mod. This allows me to load games via the sound output of my phone - or anything else with a 3.5mm audio jack. Unfortunately, I'd found that it was quite unreliable and would not load a lot of the games I'd managed to find on the internet. I put this down to the software I was using to convert the .cdt format files to .wav format being a bit flaky and my phone not outputting the volume loudly enough. And so I put the CPC away for a long while; I even pinched its Z80 processor to assist in the diagnosing of a poorly ZX Spectrum +.
|Oi! That Z80 is MINE!|
|Z80 restored and ready.|
Fast forward a couple of years and there is a rather excellent YouTube channel called "Noel's Retro Lab". As the name suggests, a very nice guy called Noel repairs and explores retro computers and games systems. And as luck would have it, he dedicated a whole video to the exploration of modding the CPC with an audio in jack. See that HERE.
To cut a long story short, my original mod was incorrectly fitted. I had attached the inputs to the actual cassette read head. While this did work it did have a couple of disadvantages. First, it seemed to need the 'Play' button pressed to pick up the input. Second, as mentioned above, it wasn't very reliable.
The NRL video is very detailed and well worth a look but, very simply, by moving the '+' side of the input to the correct side of capacitor C317 (the red wire), this meant that the input signal would pass through the op-amp circuitry of the CPC, giving a strong and stable signal at just the right location. And no need for the tape 'Play' button to be pressed.
|New wiring - thick black|
and red wires re-soldered
I also moved the black negative wire from the play head to a more generic 'ground' connection. It probably wouldn't have made any difference but not really worth taking the chance.
|I like all racing games. Even this one.|
And, again, it just worked. After about five minutes the game started straight up with no complaints. The game itself seemed OK for the time i.e. it's no Gran Turismo. With only one apparent track and quite hard time limits it's quite difficult but the graphics are cute, especially when you crash and the controls are OK, if a bit slow. I'd give the game a solid 6.5/10.