I am trying to make my own core rope rom, according to the link. I have 15mm ferrite cores, which I wound about 30 times with 1mm magnet wire. I thread the primary ( also 1mm wire) through one of the cores (once) to test it. That was connected to a diy dc pulse generator based around the 555 timer, which is fed 9v. When I first tested it, I barely got any voltage from the secondary, about 1mv according to my multimeter set to dc (my ac 200v range which is the lowest picks up nothing). I also tried connecting a low power led, which did not light up. I figured the dc was not being pulsed at a high enough frequency (7.5hz ish) so I changed the circuit for the dc pulser so that it puts out at about 45hz. However, I’m still having the exact same problem. Can anyone think of anything i might be doing wrong? At this point, I’m assuming i am not using the correct frequency. If so, is there a way I can calculate this? Any help would be much appreciated.
I do not remember the type of clock I used in this one, I think it was a square pulse generator and it was made using a simple 555 timer. Think of the circuit as transformers. Transformers work only on AC or on rising and falling edge of the square waveform. at the rising edge input, you get voltage at the output. at the falling edge input, you get reverse voltage at the output. The working principle of the ROM is very simple, it is not based on square loop cores, so any transformer can be used. The turns ratio was big, so that I can get big voltage at the output. The current out of the 555 was enough to light up the leds.
The cores used are of the 37 mix, so they work fine up to HF. But ANY core will do because you will drive it at KHz only. Just make sure the generator has enough current to provide, I am not sure if the soundcard output will work at all!