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  1. after much hassle and headache, i've finally turned for help to get this thing working. I have a simple minijack microphone (unamplified) that i want to use with my PC, but my PC requires the microphone to be amplified, so I had the bright idea of making a simple amplifier. I thought it would be simple, just hook the output (minijack out) on the collector side of a NPN transistor and hook the input (mic) at the base end. I managed to get it working, but it didn't look like that was the right way. I've attached the diagram of what I did. I wanted to get it working like a common emitter amplifier shown here: But it would not work that way. Could anyone explain why it the common emitter setup does not work for me, and show me the optimal way i can set up a minijack microphone amplifier. I would very mcuh appreciate it, thanks! -rian
  2. Oh, no, no, it says "the CPU sends out 16 data clock pulses on pin 2". The controller doesnt' generate it's own clock, the SNES CPU (or my setup) generates the clock. So it doesn't have to be a 60Hz clock. At first I thought the controller generated it's own clock too, but i tested it and it doesn't. Audioguru, i suspected that the rectified voltage would be that high, so probably that is causing the heat. I was thinking of purchasing a new AC transformer, I just wasn't sure if i had to yet, i will look into it now. Berzerk means that the clock is no longer steady. It will be high low high low low low high low low high. That only happens when the 7805 gets too hot, and i have to cool it down before it's steady again. Any theories as to why? I'm going to try out a new setup with the 4.7K resistor you suggested and a lower tranformer. I'll post how it turns out. THANKS!!
  3. I have a Mac Performa 6500/250 PowerPC Processor. It's pretty old and arguably useless for modern day GUI usage (netscape will freeze, lots of the long dead lock waits accompanied with the preX MacOS). It came with 32MB of Ram, and I upgraded to about 96MB along with an 8GB from 4GB hard drive. It's in wide and busy usage as my SMTP+IMAP server running NetBSD 1.6.1 and I'm very happy with it. Once it has gotten an 101 day uptime (the run finished with a thunderstorm and a power outage), so it is VERY stable. The uptime has been on and off since it's ths summertime and power outages are weekly the rainy miami weather. It was made circa 1995, maybe april. -rian
  4. I'm positive the 7805 overheats because it heats the whole breadboard up, and with less ICs (just the counters) the clock signal is perfectly stable (otherwise it's stable for a few seconds, then goes bezerk). The transformer I'm using is 13.5 volts, and the 7805 shoudl handle up to 20 volts, so it's probably a Amperage problem, and I'm not quite sure how to handle that (maybe a resistor before the rectifier). Audioguru thanks for the tip with the clock signal. The truth is, I really don't know any other way to set up a clock signal then with the way I use (I'm don't have a degree and I'm just a beginner). I'll look up the Schmitt-Trigger you talked about. The whole setup is to decode the serial output from a SNES controller, and represent it parallel-ly using the 74F673A IC. I use info from http://www.gamesx.com/controldata/snesdat.htm and http://www.gamesx.com/controldata/nessnes.htm. And it's been reliable because i've checked the incoming serial data with an LED manually and it works as it should. Thanks for the tips!
  5. I'm trying to decode serial data using a 74F673A 16-bit serial-in/parallel out IC. I use two 7490 decade counters along with a AND gate to give me a HIGH signal on the 16th count (counter is set to count from 0 to 16). The high signal should activate the 74F673A to parallel load the storage register from the shift register and should also activate the incoming serial data to retransmit. After having these many ICs connected to the power supply, i think the 7805 overheats because the clock signal becomes [very] unstable which is terrible for the serial transmission. Does anyone have any tips for me to get this circuit to run better. Thanks!
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