Search found 124 matches

by Bern
Wed May 24, 2006 10:42 pm
Forum: General Discussion
Topic: Voltage Regulation
Replies: 12
Views: 3104

Voltage Regulation

Looking for a suggestion on a voltage regulator. It will be used in a system with batteries, and running continuously. It will be supplying about 4 or 5 volts, at a current of less than one milla-amp. Looking for minimal drop out voltage and operating power. The normal regulators have idle current o...
by Bern
Wed May 03, 2006 10:36 am
Forum: General Discussion
Topic: Conducting fabric
Replies: 6
Views: 1937

Conducting fabric

In replacing batteries in a flashlight I found a piece of what looks like just fabric. This is glued to a foam backing, and is the contact and conductor for the circuit. Appears like it should be cheap and very easy to use in many projects. It would replace springs and contacts. Hopefully it would n...
by Bern
Tue May 02, 2006 11:42 pm
Forum: General Discussion
Topic: capacitor reverse V
Replies: 3
Views: 1184

capacitor reverse V

I have a circuit where occasionally the voltage will reverse across a capacitor. When this happens, it is for a few seconds only, and about three volts max. on a thirty-five volt capacitor. The maximum current available at this point is about five micro-amps. Which type of capacitor will take this c...
by Bern
Thu Apr 27, 2006 8:09 am
Forum: General Discussion
Topic: People detecting
Replies: 7
Views: 2613

More info.

The targets (people) will be approaching the sensing units. They will not be crossing a beam or beams. That is the catch. -- Jwax you have the idea. I don’t see any problem in processing the data, once I have it, but getting cheap sensors that provide the inputs is where my questions lie.
by Bern
Wed Apr 26, 2006 10:43 pm
Forum: General Discussion
Topic: People detecting
Replies: 7
Views: 2613

People detecting

I need a way to detect people approaching. Thinking about using ultra-sonics, something similar to the way Polaroid used to do their camera focusing. Need to detect them at about twenty-five feet, and less. Any suggestions on transducers that can do the job, at the best price? (Need lots of them) IR...
by Bern
Wed Apr 12, 2006 6:54 pm
Forum: General Discussion
Topic: PCB Supplies?
Replies: 5
Views: 1933

Thanks, Eng. 1138 & philba. -- Circuit specialists.com, is new to me. I will check them out. Philba, what I want is somehow to plate the copper so there is not the oxidizing problem. Your right, thru hole plating is more than what I want to do at this time. -- Thanks guys!
by Bern
Wed Apr 12, 2006 1:54 am
Forum: General Discussion
Topic: PCB Supplies?
Replies: 5
Views: 1933

PCB Supplies?

Where is a good source of PCB making supplies? I’m looking for a better source than what Radio Shack provides. What etchant do you use, and where do you get it. Same question for plating. -- Thanks
by Bern
Sun Mar 12, 2006 10:45 pm
Forum: General Discussion
Topic: Swap meet?
Replies: 22
Views: 7053

Re: Swap meet?

Ya, I guess I hear what you are saying. There are those that would abuse what the original intent was.
by Bern
Sat Mar 11, 2006 5:32 pm
Forum: General Discussion
Topic: Swap meet?
Replies: 22
Views: 7053

Swap meet?

I messed up and ordered some surface mount ICs when I needed DIP packages. I can’t believe I will ever use them, but not worth the hassle of returning them. What to do with them? I would be glad to send them to someone who could use them, for just the postage. I also have several other ICs that are ...
by Bern
Wed Mar 08, 2006 10:47 am
Forum: General Discussion
Topic: PLL Question
Replies: 4
Views: 1246

Re: PLL Question

Stephen in reading your explanation, I think you have me aimed in the right direction. With zero or low V on pin 9, the input current available at pin 11 is not available to the mirror because of internal N1 being shut down. With pin 12 floating, the mirror has nothing to work with. If I put about a...
by Bern
Wed Mar 08, 2006 10:38 am
Forum: General Discussion
Topic: PLL Question
Replies: 4
Views: 1246

Re: PLL Question

Edd, the way I read the frequency charts, they refer to selecting R1 and C1 for the center frequency, with R2 at infinity. If offset is needed, then there are charts for selecting R2. Because of this there is no connection to pin 12 (R2), Am I missing something? (It’s a CD4046B) Between pins 3 & 4 I...
by Bern
Tue Mar 07, 2006 11:34 pm
Forum: General Discussion
Topic: PLL Question
Replies: 4
Views: 1246

PLL Question

Thanks, MRAl: I built up a circuit using a CD4046B, phase locked loop. -- It oscillates in bursts. If I touch my finger or a scope probe (10 Meg) to pin 12, it appears to operate proper. I find the spec sheets not clear on this offset frequency, input pin. They don’t specifically say what to do with...
by Bern
Tue Mar 07, 2006 5:36 pm
Forum: General Discussion
Topic: Frequency Multiplying
Replies: 11
Views: 2495

Re: Frequency Multiplying

MRAL --- I sent you an E-Mail with a question on your reply. If you did not receive it. please let me know and I will contact you another way. -Thanks
by Bern
Sat Mar 04, 2006 10:05 pm
Forum: General Discussion
Topic: Frequency Multiplying
Replies: 11
Views: 2495

Re: Frequency Multiplying

I now have a 14 KC free running oscillator which I use, and I’m hoping if it is not drifting around in phase with 60 cycle, it will do its job better. It is being used as an exciter for a monitoring application I am building. -- Yep, Dean, that is what I am after. Looking at a signal that is down in...
by Bern
Sat Mar 04, 2006 2:02 pm
Forum: General Discussion
Topic: RC Lawn Mower - Update Please
Replies: 7
Views: 1768

Re: RC Lawn Mower - Update Please

One method I want to do some day, is bury a wire along the route I want the mower to go. Insert some RF into that wire, and have two sniffer coils on the front of the mower to track the RF signal. Some circuitry and mechanical steering can then be used to guide the mower along the way.