Search found 98 matches

by gadgeteer
Sun May 18, 2003 12:40 am
Forum: General Discussion
Topic: Equalizer
Replies: 8
Views: 1636

Re: Equalizer

Pop the case screws and tell us what you see?
by gadgeteer
Sun May 18, 2003 12:29 am
Forum: General Discussion
Topic: Rear View Mirror
Replies: 12
Views: 2124

Rear View Mirror

Since TOPICS have been DEAD lately, thought I'd share a tip...<p>I wanted an "Electro-Chromic-Rearview-Mirror" (electronically dims when your tailgator has his brights on); $250 dealer, $25 salvage. But it was HEAVY --- mount promptly fell off the windshield. And then at least once a year afterards,...
by gadgeteer
Sun May 18, 2003 12:13 am
Forum: General Discussion
Topic: Timer circuit
Replies: 12
Views: 1921

Re: Timer circuit

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Connect a 0.1uF capacitor from pin 2 to the junction of the dash-mounted light and the switch which grounds it. <hr></blockquote>Exactly how I woulda wired it. 555 is NOT "edge triggered", so if you don't convert the s...
by gadgeteer
Sat May 17, 2003 11:46 pm
Forum: General Discussion
Topic: 555 output in m.a
Replies: 6
Views: 1330

Re: 555 output in m.a

Couple hundred. Unless you're talkin' about the CMOS version, 7555; I don't remember, think it's 100 max...
by gadgeteer
Sat May 17, 2003 11:41 pm
Forum: General Discussion
Topic: radar jammers
Replies: 2
Views: 843

Re: radar jammers

I have a unit from "Rocky Mountain". Actually, I have TWO of them --- ordered a second one 'cause it said it also jams LASER. There's not alot to them, the LASER just adds one resistor and one infra-red emitter. The entire circuit is an 8-pin-Pic chip, which outputs a simple audio tone, one to two K...
by gadgeteer
Wed May 14, 2003 10:51 pm
Forum: General Discussion
Topic: make an alarm system
Replies: 2
Views: 633

Re: make an alarm system

Aha! Someone's been driving with the parking brake on! Back when I was in high school, I was in the MARCHING BAND; one trip, a gas-station-attendant came running out to one of the school busses shouting, "HEY! Do you know you have FLAMES coming from under the BUS???" Driver had left the brake on...<...
by gadgeteer
Wed May 14, 2003 3:25 pm
Forum: General Discussion
Topic: 12 volt delay for relay
Replies: 2
Views: 746

Re: 12 volt delay for relay

OH if you use a DARLINGTON transistor, your capacitor will see a volt and a half max. Electrolytic capacitors have a bad habit of drastically changing capacitance over time if they are severely under-voltaged...
by gadgeteer
Wed May 14, 2003 3:21 pm
Forum: General Discussion
Topic: 12 volt delay for relay
Replies: 2
Views: 746

Re: 12 volt delay for relay

You won't get simpler than one transistor, one resistor and one capacitor. Use an NPN with sufficient power to drive your relay, emitter tied to ground; then tie the base HIGH with a resistor (limited by your relay current, divided by transistor current gain --- a 10k resistor will provide ~1 mA, if...
by gadgeteer
Sat May 10, 2003 11:43 pm
Forum: General Discussion
Topic: headphone speakers
Replies: 2
Views: 876

Re: headphone speakers

I would suggest BUYING a cheap headset and cannibalize them. I bought a set of 18-25000hz at Big Lots for about $4...<p> May I suggest you find headphones rated at 15hz - 25khz or better? If you buy 20-20k, odds are they are LYING, and just GUESSED at the frequency; but even if TRUE, those two point...
by gadgeteer
Sat May 10, 2003 11:02 pm
Forum: General Discussion
Topic: Car stereo buzz problem
Replies: 8
Views: 1727

Re: Car stereo buzz problem

Filters are a good idea, but a new power supply might be simpler. Current draw on the CD player should be quite low, lending itself to a linear regulator. These can be bought for $7 - $15; they contain some way of selecting the output voltage, usually a slide switch. There is a way to choose the cor...
by gadgeteer
Wed May 07, 2003 11:25 pm
Forum: General Discussion
Topic: Wir müssen wissen. Wir werden wissen.
Replies: 1
Views: 563

Wir müssen wissen. Wir werden wissen.

"We must know. We will know."<p> ;) @ Analogee...
by gadgeteer
Wed May 07, 2003 12:57 pm
Forum: General Discussion
Topic: Video Camera Detector Schematic?
Replies: 27
Views: 4044

Re: Video Camera Detector Schematic?

No-vice, you seem to be talking about an ACTIVE device --- as in "jammer". The VCD-42 is PASSIVE; it's merely a receiver . The point is that this will inform you of any electronic device nearby that contains a 15,750 oscillator; 'cause such a device will be some kind of VIDEO circuit . By "sweeping"...
by gadgeteer
Tue May 06, 2003 11:52 pm
Forum: General Discussion
Topic: Video Camera Detector Schematic?
Replies: 27
Views: 4044

Re: Video Camera Detector Schematic?

I received the VCD-42 today. As with most of what I own, the screws came out within the first couple of minutes. I found --- a simple ferrite bar, length about 4 inches, with a single coil around it. Hot-glued to the board. Looks like the inductor is paralleled with a poly-styrene capacitor --- unma...
by gadgeteer
Tue May 06, 2003 11:32 pm
Forum: General Discussion
Topic: singing trophy
Replies: 1
Views: 545

Re: singing trophy

A "Hall Effect Sensor" produces a voltage in the presence of a magnetic field. You could build one of the circuits from the internet, like this 555-based one , or you could build this one . The SECOND should easily interface to a Radio Shack digital recording/playback module. The trophy needs to be ...
by gadgeteer
Thu May 01, 2003 7:41 pm
Forum: General Discussion
Topic: LM3909
Replies: 0
Views: 591

LM3909

In my "grubby little hand" are some 50 pieces of LM3909 LED flasher. They cost me under 4 bucks each, including shipping, tax, gratuities, hamster charges, etc. Has anyoe here been looking for one of these? AS YOU KNOW they were obsoleted recently by NS. There are SO MANY CIRCUITS you can do with th...