Search found 543 matches

by russlk
Tue Feb 10, 2004 1:46 pm
Forum: General Discussion
Topic: whats the difference?
Replies: 7
Views: 3073

Re: whats the difference?

VA stands for volt-amps. volt-amps divided by volts = amps.
by russlk
Sun Feb 08, 2004 6:58 pm
Forum: General Discussion
Topic: 1v to 5v output
Replies: 10
Views: 4898

Re: 1v to 5v output

Sounds like a voltage divider to me.
by russlk
Wed Feb 04, 2004 7:33 pm
Forum: General Discussion
Topic: Tektronix 485 scope repair help needed
Replies: 13
Views: 7635

Re: Tektronix 485 scope repair help needed

Sounds like a simple problem, but I need a schematic. If you can scan the power supply section and email it, I will try to help.
[email protected]
by russlk
Sat Jan 17, 2004 6:33 pm
Forum: General Discussion
Topic: Permanent magnet motors...
Replies: 10
Views: 6949

Re: Permanent magnet motors...

E X I = power input. Can't put more power in, can't get more power out.
by russlk
Wed Jan 07, 2004 7:05 pm
Forum: General Discussion
Topic: electronic off switch
Replies: 4
Views: 2140

Re: electronic off switch

The parking lights on my truck are on when the headlights are on, so putting the relay between then would not work. Seems to me that all your running lights should be on when the headlights are on. A more useful use of the relay would be to turn the headlights off when the ignition key is off. My su...
by russlk
Wed Jan 07, 2004 6:57 pm
Forum: General Discussion
Topic: old dos manuals
Replies: 1
Views: 1504

Re: old dos manuals

I have seen then at yard sales, and stores specializing in used goods are a good place to look. Have you tried Amazon.com or ebay.com?
by russlk
Tue Jan 06, 2004 7:49 pm
Forum: General Discussion
Topic: control computer power
Replies: 12
Views: 4677

Re: control computer power

How do you get it turned on again?
by russlk
Tue Jan 06, 2004 7:47 pm
Forum: General Discussion
Topic: transmitter / receiver
Replies: 7
Views: 3423

Re: transmitter / receiver

Check out various garage door openers. Is this line of sight?
by russlk
Fri Jan 02, 2004 7:13 am
Forum: General Discussion
Topic: Kodak Photo Resist (KPR)
Replies: 8
Views: 7623

Re: Kodak Photo Resist (KPR)

I hope that a pint once a month will not be a problem, because I do it. Once a day is probably too much.
by russlk
Fri Jan 02, 2004 7:06 am
Forum: General Discussion
Topic: Schematic CAD program?
Replies: 10
Views: 7159

Re: Schematic CAD program?

Switcher Cad III is a schematic capture program free from Linear Technology. The logic symbols are limited, but you can draw more.
by russlk
Thu Jan 01, 2004 10:14 pm
Forum: General Discussion
Topic: Higher voltage adjustable volts amps power supply
Replies: 5
Views: 2567

Re: Higher voltage adjustable volts amps power supply

I don't understand all of the "laboratory supply" schematic, so I designed one that I do understand. I have not built it, of course, so no guarantee. You will need a good heat sink, the two IGBTs dissapate 105 watts min. If the supply is to be variable, the 7 volt difference between input ...
by russlk
Wed Dec 31, 2003 7:48 pm
Forum: General Discussion
Topic: Higher voltage adjustable volts amps power supply
Replies: 5
Views: 2567

Re: Higher voltage adjustable volts amps power supply

R2 and R3 set the output voltage, but you cannot just change Q3, a re-design is needed to increase the current from 150 mA to 15 amps.
by russlk
Sun Dec 28, 2003 5:06 pm
Forum: General Discussion
Topic: Transformers
Replies: 1
Views: 1481

Re: Transformers

Using an ohmmeter, measure from each wire to all the other wires in order to determine which are connected. These are most likley switching supplies which operate at a high frequency, 20kHz to 100kHz. You can use a signal generator at low voltage to determine the turns ratio. The voltage ratio is eq...
by russlk
Fri Dec 26, 2003 4:31 pm
Forum: General Discussion
Topic: LM3914 Help??
Replies: 6
Views: 3090

Re: LM3914 Help??

What is an uf meter? I have no idea whether these are compatable.