That part is fine. I was confused with HC logic which is available with a lower voltage threshold for use with older TTL and that might explain the duty cycle....
hello , im the new guy , good day to all, now for my silly science and electronic stuff Sometimes i go drinking at er..um the strip club till late night. I go...
Sounds more like "impaired science"! : ) Anyway, maybe there are some other explanations. Maybe they just know where they are going and they don't hang out in...
At 04:29 PM 11/25/2005, you wrote: Charles, I have modeled your ion chamber bias power supply in LTSpice. In simulation - it doesn't get above 32 volts. I can...
Well, I don't know. I'll go measure it right now to make sure... I measure 46 volts with a 1000 megohm load and it was creeping up. I have a fresh battery...
I found a mistake. I left out a diode between the last stage and the 4uF filter. The last diode and the 10nF should connect together and then pass through...
I just made the change. Thanks again, Charles ... From: techlibdotcom@yahoogroups.com [mailto:techlibdotcom@yahoogroups.com] On Behalf Of Eric Vogel Sent:...
The mistake was worse than just a missing section. Try removing the top, right 10nF on your simulation and your voltage will go from 32 to over 40! That...
I chose 50 volts for that chamber simply because that is what the original circuit used and I was hoping to maintain some semblance of calibration. That all...
At the risk of disturbing a sleeping forum... I'm fumbling through reinventing the wheel on a radiation counter power supply. The output is clear - that's a...
"Sleeping" is such a nice way to put it. : ) The problem with my circuit is that it can't supply much current, barely enough to run a Geiger tube. But, on the...
I was successful in making a simulation run but I had to do a couple of things. I found a model for the MPSA18 and made my own 120 volt zener by modifying the...
I forgot to mention that was with 100 ohms resistance in the 10 mH choke. When I set it to 60 ohms which is more near my real chokes, the voltage climbs faster...
Hi all, I am working on a home project right now that might be called an "optical multimeter". It uses a 3.7 x 3.7 mm square silicon PIN photodiode as the...
Hi Friends, I have built 3 EDMs using stepper motors and now I am trying to experiment with a CNC -Wire EDM project. I intend to share my views and experiences...
I had a question about the 4-Transistor Amplifier for Small Speaker Applications circuit that you have posted on the web site. You have stated that the gain...
... I would add a small pico cap as a filter, to pull off some of that noise. I think what youre hearing is some oscillation of the transistors. Try some feed...
I don't generally recommend messing with radioactive substances! I have heard of people burning the mantles to concentrate the thorium in the ashes but I've...
Hi Charles, I tried to email you directly, using the email address at your website, but the message was bounced back. Then, I noticed the forum option at the...
Our email was misdirected last weekend but it should be working now. I've been moving all our websites to our own server but somehow managed to break the...
Greetings all ... I am in the process of rebuilding a '72 Alfa Romeo and I want to add a circuit to "chime" if the key is left in the ignition or if the head...
Years ago I added an audio alert to an electronic scale and, much to my surprise, it sounded exactly like the chime on the typical airplane telling you to...
Hi Charles, Thanks for your quick response. If it's not much trouble, I'd appreciate you adding the schematic to your website as you suggest. Thanks, Eric ......
I just added it below the two gate circuit. I used a '4069 for all four gates and it seems to work nicely. ... appreciate ... the web. ... forum ... circuit, ...
I came up with a circuit that sounds pretty good. See the bottom of http://www.techlib.com/electronics/noisemakers.html. I hope I drew it right; it seems like...
Thanks again, Charles. I will definitely put that circuit to good use sometime soon. BTW, for the 5v beeper you show in the original, what kind of beeper is...
