T&L Publications

no free lunch huh.... I was kinda hungry for a perpetual motion device myself. lol

if you're saying that the line level sound that your VCR puts out is too high i dont think that any inline device will correct the distortion. the distortion is probably coming from the pre-amp inside the vcr and any inline device will just lower the amoplitude but the distortion will still remain. ...

actually i have Electronics Workbench on a CD I could send you. Email me if your interested.
[email protected]

I thought at first it was because of a wimpy power supply but i've tried a 12v motorcycle batt. ive put some small ceramic caps from the control pins to gnd and from the +V for the chip to gnd. I am using it to drive a 32ohm speaker, ive added about 2k in series with it to limit current.<p>(Edit) Ju...

I tried setting up a 556 with both halves running in astable. each half alone works fine when i want to run both halves in astable at the same time it doesn't work. The adjusting the timing pots on one side changes thew other half to the same freq no matter what that sides pot is set to.<p>Someimes ...

1=700+900
2=700+1100
3=900+1100
4=700+1300
5=900+1300
6=1100+1300
7=700+1500
8=900+1500
9=1100+1500
0=1300+1500<p>are these tones wrong that i have?

hey thats pretty slick but the tones they list are different from the ones i have. (UK tones maybe?) The ones i have are all combinations of 700hz thru 1700hz in steps of 200hz. And what are the tones listed as A, B, C, and D used for? Are these some type of operator control tones? Or are the tones ...

Ok i don't have any exp with radio stuff. But aren't radio freqs alot higher than DTMF. I suppose i could use a freq divider but then ill need 7 different freqs to make all the DTMF tones. I know what youre talking about though they use those in the new xtal less recievers for RC cars. Ill have to a...

Or maybe would it be easier to use an old phone as a keypad?<p>Dean, do you have any suggestions?<p>[ April 23, 2003: Message edited by: unknown_entity ]</p>

I have a DTMF decoder hooked up to an answering machine to pull digits from a dial tone and i plan on using it to turn on and off lights in my home. I have the basic idea and everything set up to have an answering machine pick up and leave dial tones as a message. This turns on and off lights in my ...

i might be able to get aroung using an amp cause i was messing around with some breadboard stuff today and it worked pretty good without one

ok im looking at the pinout of this chip, can't make sense of it. I have never used op amps before so i not sure what goes to what.<p>8 Pin DIP --------------------- .....Gain**1--o--8**Gain ..-Imput**2-----7**Bypass .+Imput**3-----6**Vs .....Gnd**4-----5**Vout<p>Better yet i tell ya what i want to ...

nothing better to do huh. Well the other day in lab I made a nifty little coil gun type thing out of a camera board and some magnet wire around a piece of 1/4" copper tube. For just throwing it together between class it was pretty good. After it charged up a little bit it would shoot machine sc...

Ok Greg i see now. But one last question, Is it possible to vary the duty-cycle/pulse width without effecting the freq.<p>Russ, is this available online somewhere? Or maybe if you have it can you scan it and emauil it to me? "National Semi application note AN694 page 7 shows an example"<p>...

Ok i get how it will change the duty cycle and pulse width cause these are one and the same (right?). But How will this change the freq? The only way i can see that it will effect freq is if the pot is turned so high that it will trigger wrong or not at all. Can someone please explain how it will ef...