Search found 98 matches

by gadgeteer
Mon Mar 10, 2003 12:47 pm
Forum: General Discussion
Topic: 50A or greater
Replies: 19
Views: 4238

Re: 50A or greater

Use of a battery gets rid of massive filter caps; but it's not a good idea. Problems are "overcharge", "venting", "destruction of battery".<p>I think what Joseph was saying, was take a simple resistor-zener-diode chain, and amplify it with a common-collector. Which will output Vz + Vbe (in silicon, ...
by gadgeteer
Mon Mar 10, 2003 12:26 pm
Forum: General Discussion
Topic: Age?
Replies: 24
Views: 3638

Re: Age?

I am 39 years old. (And I shall soon celebrate my fifth 39th birthday...) <p>Seen on a pillow: "Age is a number---mine is unlisted..."<p>I attended the 1964 New York World's Fair---almost remember it. Remember fondly the cartoons and television of the 60s---programming was so much more innocent then...
by gadgeteer
Mon Mar 10, 2003 12:07 pm
Forum: General Discussion
Topic: Are most people here Electrical/Electronics engineers?
Replies: 36
Views: 5976

Re: Are most people here Electrical/Electronics engineers?

I'm supPOSED to be an electronic engineer. Worked for the same company ~8 years, they were bought out. I was canned. Hired back, whole department canned, everybody canned, building sold. We were steamed that the new company pretended "this was just market driven, we DID not PLAN this from the BEGINN...
by gadgeteer
Fri Mar 07, 2003 10:30 pm
Forum: General Discussion
Topic: low voltage LED
Replies: 9
Views: 1472

Re: low voltage LED

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Does it need to be done with a chip? A few transistors can do what you ask.<hr></blockquote>Heck ONE darlington would do it. At the currents required for a modern super-bright LED, such as 10-15 milliams, the darlingto...
by gadgeteer
Fri Mar 07, 2003 9:40 pm
Forum: General Discussion
Topic: inexpensive TO-220 mounting hardware?
Replies: 11
Views: 1669

Re: inexpensive TO-220 mounting hardware?

Can you use a TO-126 part? It has the plastic screw-hole, no need for a shoulder washer. Also, most any thin insulater works---even polyester or polyethylene. Just use the white grease.<p>If insultation isn't critical, I've had good results with a bit of SUPERGLUE (no grease)---it conducts heat fair...
by gadgeteer
Fri Mar 07, 2003 9:27 pm
Forum: General Discussion
Topic: Radiation Monitors
Replies: 3
Views: 735

Re: Radiation Monitors

I am SO glad I bought the kit from Chaney (now Electronic Goldmine). It is no longer available. It has the sensitive detector tube, capable of sensing low-level alpha and beta radiation. (It actually detects spurious emissions from tritium lights...) I used a Radio Shack battery enclosure---think it...
by gadgeteer
Fri Mar 07, 2003 5:43 pm
Forum: General Discussion
Topic: LED Sign's
Replies: 4
Views: 1035

Re: LED Sign's

Local guy is building some here---the size of a BUSINESS CARD (well, a little thicker). Accessory module connects to your PC for programming the thing. Runs off of lithium batteries.<p>www.LightTags.com<p>They were selling them at the fair for $60---I think retail is ~$75...
by gadgeteer
Fri Mar 07, 2003 5:08 pm
Forum: General Discussion
Topic: Video Camera Detector Schematic?
Replies: 27
Views: 4285

Video Camera Detector Schematic?

Anybody have a schematic (or a weblink to one)? I'm wanting device that detects the HORIZONTAL frequency (15,750 Hz), not the "RF Transmitter detector". <p>They usually have a range of 3 ft to 20 ft, and will detect cameras that operate without transmitters (coax runs to monitoring room or VCR)...<p...