Search found 8 matches

by wizguru
Mon Dec 21, 2009 12:27 pm
Forum: Projects & Kits
Topic: 1K-1MHz Sinewave Generator Using one Freq. Pot
Replies: 14
Views: 22571

Re: 1K-1MHz Sinewave Generator Using one Freq. Pot

Since I am unable to design this and no one else has presented a solution and I can't afford to pay for expensive parts these days, I will have to soon inform the church that I will have to un-volunteer for this project. Perhaps the kids can go into banking, sales, insurance, or become stock brokers...
by wizguru
Fri Dec 18, 2009 1:52 pm
Forum: Projects & Kits
Topic: 1K-1MHz Sinewave Generator Using one Freq. Pot
Replies: 14
Views: 22571

Re: 1K-1MHz Sinewave Generator Using one Freq. Pot

Hello. This is a donated project by me to the church. I cannot afford to pay $3+ a pop for XR2206 ICs to replenish my personal stock of them used for this project - $300+ total for 100. With all parts considered, this would bring up the project costs to an unaffordable $600+ ($6+ per circuit, includ...
by wizguru
Sat Dec 12, 2009 9:05 pm
Forum: Projects & Kits
Topic: 1K-1MHz Sinewave Generator Using one Freq. Pot
Replies: 14
Views: 22571

Re: 1K-1MHz Sinewave Generator Using one Freq. Pot

Thanks for the links. However, no link provided describes a circuit which uses only ONE pot control to control the sinewave oscillator frequency, and that is a must requirement. 1 KHz - 1 MHz is important because they want an oscillator which can be expanded to possible other future experiments, suc...
by wizguru
Tue Dec 08, 2009 9:02 pm
Forum: Projects & Kits
Topic: 1K-1MHz Sinewave Generator Using one Freq. Pot
Replies: 14
Views: 22571

Re: 1K-1MHz Sinewave Generator Using one Freq. Pot

The sinewave generators are to be used in church science class, where each young student has two of these modules, to teach these youngsters how to use various electronic test equipment, what a "pure" sinewave looks like on a scope, how sinewaves are involved in various electronic designs,...
by wizguru
Sun Dec 06, 2009 8:46 pm
Forum: Projects & Kits
Topic: 1K-1MHz Sinewave Generator Using one Freq. Pot
Replies: 14
Views: 22571

1K-1MHz Sinewave Generator Using one Freq. Pot

I am trying to design a sinewave generator, needed as part of the electronics in 100 devices I am to provide a church. The sinewave generator must be cheap, use few parts (12 or less preferred) to be compact, be tunable from 1 KHz to at least 1 MHz using only one single pot, and use commonly availab...
by wizguru
Sun Dec 06, 2009 8:25 pm
Forum: Projects & Kits
Topic: Why won't my AC adapter work with digital camera?
Replies: 5
Views: 12837

Re: Why won't my AC adapter work with digital camera?

I got it to work, but not exactly as expected. I changed by 500ma adapter for a 1250ma adapter, then adjusted it to 3.2V, and it still did not work. However, when I adjusted it to 3.4V (after changing the LM317 pot) it worked fine. So I left it at 3.5V. This is strange because my AA alkaline batteri...
by wizguru
Wed Dec 02, 2009 1:26 pm
Forum: Projects & Kits
Topic: Why won't my AC adapter work with digital camera?
Replies: 5
Views: 12837

Re: Why won't my AC adapter work with digital camera?

Thanks for responses. My adapter puts out 500ma DC. Although 500ma would seem to me to be more than adequate, you might be right, so I will try to find a 1000ma DC adapter. I have a 2200uf capacitor across LM317 output, as well as a 0.1uf poly for RF decoupling, so ripple should be very small. In th...
by wizguru
Mon Nov 30, 2009 7:07 pm
Forum: Projects & Kits
Topic: Why won't my AC adapter work with digital camera?
Replies: 5
Views: 12837

Why won't my AC adapter work with digital camera?

My Kodak C743 digital camera uses KAA2HR dual 1.2V AA battery pack (lid conductor connects pos. of one AA to neg. of other in series for 2.4V for camera). Also works with dual 1.5V alkaline AA cells. I built AC adapter using LM317 adjustable regulator IC, voltage adjustable 2.4V-3.2V. To mimic batte...