Search found 2881 matches

by haklesup
Tue Mar 02, 2004 4:13 pm
Forum: General Discussion
Topic: Pre-amp Circuit Help
Replies: 21
Views: 4344

Re: Pre-amp Circuit Help

I agree with cato in that the issue may not be the circuit design but the selection of the component.<p>The 741 is an old design and has very loose specs. Presently, there are many op amps with excellent specs. Type "op amp selection guide" into a search engine and go from there. It is likly that yo...
by haklesup
Tue Mar 02, 2004 1:09 pm
Forum: General Discussion
Topic: Connecting Portable CD player to car radio
Replies: 5
Views: 1397

Re: Connecting Portable CD player to car radio

Unless you have a schematic, you're more likly to break the radio than you are to design a line level input plug and a switch to activate it. This would require an opamp for level shifting and isolation from the main amplifier circuit. If you have a radio with say a broken tape player, you might be ...
by haklesup
Wed Feb 25, 2004 2:39 pm
Forum: General Discussion
Topic: Automotive dual battery question
Replies: 29
Views: 6381

Re: Automotive dual battery question

Do they still put big diodes between the main battery and the auxillary battery. A properly connected diode will prevent one battery from becoming a load if the other one should become too weak to fully charge or if a cell shorts out and the voltage drops.<p>In such a configuration, the Aux battery ...
by haklesup
Wed Feb 25, 2004 2:13 pm
Forum: General Discussion
Topic: 1v to 5v output
Replies: 10
Views: 2632

Re: 1v to 5v output

Since the inputs take very little current, you can do the whole thing with a voltage divider.<p>One or two fixed resistors and a potentiometer should do the trick.<p>Place the resistors and pot in series between the source (10V) and ground with the pot in the middle and the wiper connected to the in...
by haklesup
Wed Feb 25, 2004 1:45 pm
Forum: General Discussion
Topic: Wireless driveway alarm
Replies: 14
Views: 3001

Re: Wireless driveway alarm

I gather proximity sensor is IR and the communication link to the base is RF.<p>You can try to improve the efficiency of the transmitter and/or reciever by modifying the antenna it uses. Try to find the antenna node on the PCB (it may be nothing more than a PCB trace or wire stub) and extend it with...
by haklesup
Wed Feb 25, 2004 1:23 pm
Forum: General Discussion
Topic: who makes this POT?
Replies: 12
Views: 2272

Re: who makes this POT?

I have no clue, the logo on the RS website is unclear and I have no sample. Besides, the logo was unfamiliar anyway. Is there a country of origin marking on the device. <p>By offshore I meant any one of a number of OEM manufacturers in China, Taiwan, Hong kong, Malasia or Phillipines etc (S E Asia)....
by haklesup
Tue Feb 24, 2004 1:39 pm
Forum: General Discussion
Topic: who makes this POT?
Replies: 12
Views: 2272

Re: who makes this POT?

Horizontal Trim pot. probably 6mm size, Open Frame, Carbon comp.<p>Looks like<p> www.Bourns.com model 3319<p>Alps Model RH01(www.potentiometer.com bottom left link to trimmers) Alps website hard to navigate<p>Panasonic (didn't look it up but they are a primary OEM) <p>Also take a look at Ohmmite, Cl...
by haklesup
Mon Feb 23, 2004 4:50 pm
Forum: General Discussion
Topic: measuring AC/DC Amps
Replies: 6
Views: 1518

Re: measuring AC/DC Amps

Ideally, the clamp on meter probe will not measure any DC component. If you do get anything off your alternator, it is just ripple current or the big surge you get when you turn on or off current.<p>66% factor is that proportion of the answers that will make sense ;) (Sorry, just kidding. I couldn't...
by haklesup
Thu Feb 19, 2004 1:34 pm
Forum: General Discussion
Topic: lightning strike
Replies: 13
Views: 2927

Re: lightning strike

I don't think that NEC has anything to say about structural protection from lightning except to how it pertains to protecting the active electrical distribution system like the breaker box and service connections.<p>In general, only the local building code would require lightning protection and prob...
by haklesup
Wed Feb 18, 2004 3:09 pm
Forum: General Discussion
Topic: Internet Bandwidth
Replies: 19
Views: 4373

Re: Internet Bandwidth

It seems both definitions are correct. We may all have to increase our intellectual bandwidth to accept alternate definitions as the technology progresses further. That's how the english language works (among others). In fact websters (www.m-w.com) lists both definitions while britannica only lists ...
by haklesup
Wed Feb 18, 2004 2:41 pm
Forum: General Discussion
Topic: need chip ID
Replies: 7
Views: 1852

Re: need chip ID

Excese my ignorance, but why is it called a "Jungle" IC. Does it have a more technical sounding name I might see in a listing of parts?
by haklesup
Fri Feb 13, 2004 2:11 pm
Forum: General Discussion
Topic: lightning strike
Replies: 13
Views: 2927

Re: lightning strike

Given that you'll be using the shelter during a storm when lightning is likely, grounding the pipe to a ground spike is worthwhile even if it is not absolutely necessary. <p>Assuming the stove is bolted to the pad and the cement is in intimate contact with the earth, it could provide an adequate gro...
by haklesup
Fri Feb 06, 2004 2:29 pm
Forum: General Discussion
Topic: digital speedometer
Replies: 16
Views: 4010

Re: digital speedometer

"Unfortunately when the vehicle is stood still and you accelerate the speedometer registers a value. I have no idea what this means,"<p>I interpret this to mean that the display registering a speed when the vehicle is in neutral but you are reving the engine.<p>I might guess that you have put the se...
by haklesup
Wed Feb 04, 2004 4:09 pm
Forum: General Discussion
Topic: MY FRIENDS SAY I AIN'T RIGHT
Replies: 13
Views: 3216

Re: MY FRIENDS SAY I AIN'T RIGHT

Sounds like your a couple months early for an April Fools joke. I always enjoyed that article in the now defunct Radio Electronics in the April edition (for a few years anyway). My favorite was the Macrowave oven which purported to make food colder by emitting longer microwaves. Apparently some read...
by haklesup
Thu Oct 02, 2003 4:09 pm
Forum: General Discussion
Topic: RPM regulation
Replies: 55
Views: 13924

Re: RPM regulation

There is another although less efficient way to regulate the output. That is to let the RPM of the generator vary and feed the AC output into a rectifier then back into an inverter (AC-DC-AC converter). This basic scheme is used by wind turbines. If you get a good inverter (off the shelf) then the v...