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Some Mail are worth reading, but i was unable to reply, it is recorded here. Join the group and respond on this wiki-forum. These mail need a solution and your reply will help. I will also try.

I may not post mail here that need to be confidential : like those that are technology specific or sent as a company correspondence for design service.

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Simple Digital Counter - How To

posted Dec 25, 2011 7:08 AM by Anantha Narayan [ updated Dec 25, 2011 8:53 PM by Anantha Narayan ]

I really find your entire site very informational! I'm an old-time C and C++ programmer, but I'm fairly new to electronics. I have a question about the schematic of the Simple Digital Counter. For example, on pin 7 (CO) of the 4029, there is a bubble or circle, as there are on other pins. I know that on logic symbols that the bubble or circle means the input or output is inverted. What does it mean when it applies to an IC? ,

Keith E. Cooper koothkeeper.com

delabs Said -

Your guess is right. Learn more Here - http://www.play-hookey.com/digital/

You can learn some basics here - http://solderman.dapj.com/

| 1 comment

LM3914 meter for 25 V DC

posted Dec 25, 2011 7:03 AM by Anantha Narayan [ updated Dec 25, 2011 7:04 AM ]

Dear Sir,

I wish to assemble a bargraph display to indicate approximately 25volts dc.How many LM3914 I should cascade? How to calculate resistor value which is grounded from the junction of Pin 6 & 7(Rhi &Ref.out)? Assuming i need to cascade 3 LM3914s,what is the method to cascade these ics? The display need not be precise or very bright. I hope you can help me out.

I shall be very grateful. Can we do it in such a way that the first LM3914 displays 1-10 v & second 11-20v & the third 21-30v?

Thank you again

Mail from AD in Yahoo

555 Astable Oscillator Burning

posted Dec 25, 2011 7:00 AM by Anantha Narayan [ updated Dec 25, 2011 7:00 AM ]

Thanks for the helpful website. I was building an astable oscillator with the 555 and really found your simulation useful for picking the components. Now, if I can only stop burning up the chip!

Mail from PH of MD USA

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