This is a new way to have a techlib.com discussion forum that will avoid all the spamming my old one was experiencing. Let me know if you like the change and...
Wow, nice site, in this age of computer simulation it's great to find someone who still remembers which end of the soldering iron to hold :- ) My interest is...
I have a 2-axis stepper motor controller that takes TTL level inputs as an option for driving the motors. By default, each of the 4 direction inputs is high....
As often happens I found the "transistor as gigaohm resistor" references again after I had posted this. This http://home.flash.net/~evogel/ev-schu.html...
I have plenty; just email me your shipping address (and a reminder of what you want). I'm on vacation so it might take a couple of weeks. Those old radiation...
I would use a comparator or even a line receiver (which is just a comparator). Connect the joystick in series with a resistor, say 10k, from 5 volts to ground,...
I think you'll need two comparators for each pot because you'll want a dead zone in the middle where no motor is running. For example one comparator would...
Thanks, I'll email you. Steve charleswenzel <charles@...> wrote: I have plenty; just email me your shipping address (and a reminder of what you want)....
Thank you for your timely help! A quad comparator is what I went with. There is some "bounce" or lag when a couple of inputs are driven low by the joystick...
Many quad comparators need pull-up resistors on the outputs but your load probably provides that function. A high value resistor, say 1 to 10 megohm, from the...
Yes, I agree the feedback resistor would be a better solution than my schmitt suggestion (which was actually a pretty bad idea now I think about it some more),...
In your classic article on AM antennas you give a schematic for an untunned ferrite AM antenna that is directional. It interestes me since I must place my...
Forgive my ignorance, can you explain what the feedback resistor from the output to the positive input will do to reduce bounce? My guess is that once the...
Good guess, that's it. The comparator is very sensitive so it doesn't take much noise at the input for it to switch back again when the input is still close to...
Yes, that amp is probably pretty hard to find but there is probably something equivalent out there. I intend on redesigning that project when I get home from...
I was thinking either using an NE529 or philips if amplifier exact model skips my mind belive it starts with sa???? I havea jar of these phillips chips ...
I think you mean NE592 which should work great. I was thinking along the same lines, maybe an LM733, if they are still made. I do like the AGC feature but it...
... since ... thick. ... purpose. ... informed ... I was able to receive a MC1590 from Charles sometime ago.I built the (fig 5 ferrite antenna with built in...
Ha! I just looked at the schematic and I didn't even use the AGC function. Oh well. Anyway, it looks like an LM733 (MC1733) should give about the same...
Boltek makes lightning detectors http://www.boltek.com/stracker.htm which work pretty well. My question is how do they manage to get an LF/MF direction finding...
I don't really know what is inside but to get direction info from such a small space makes me suspect that higher frequencies are used. Maybe there are three...
Now that I think about it, it doesn't seem likely that they are resolving phase in that small of a space; the delay is just too short. I still like the VHF...
There are prof VHF lightning systems, used with the LF systems, but while I can see getting some directivity in that sized space in the GHz range, but I'd have...
I agree. It is hard to imagine reflectors and directivity at VHF in that small space but it is equally hard to imagine resolving the direction ambiguity at LF,...
http://www.lightningsafety.com/nlsi_lhm/detectors.html From the above site. Boltek Stormtracker in the Low Frequency Range 100-700 KHZ?; ... sense ... an...
Hi Charles! I want to design 20W VHF power amp. for my FM TX because I found an already designed one at a website, but I couldn't found the required values of...
A good source for ham project parts is Dan's Small Parts http://www.danssmallpartsandkits.net/ ahmed73500273 <ahmed73500273@...> wrote: Hi Charles! I...
I bet I couldn't find those trimmers in my "big" town, either! Those are pretty big values and a small trimmer is likely to not be very stable or able to...
