Hobby Electronics Basics

Op Amp Comparator hysteresis

I see circuits that add hysteresis to op-amp comparators by putting a positive feedback resistor network that acts as a...

15 comments posted 13yrs

posted by panfilero

15 comments posted 13yrs posted by panfilero

Center Tapped and Regular Transformer

Hi, Could you please explain the following points regarding a center tapped transformer (some questions apply to a non-...

39 comments posted 13yrs

posted by anand.paralkar

39 comments posted 13yrs posted by anand.paralkar

Digital stereo audio to 'old analog stereo'?

Is there an adapter one can purchase so one can use older stereo equipment with a new flat screen digital TV? My new TV...

7 comments posted 13yrs

posted by footboarder

7 comments posted 13yrs posted by footboarder

El-cheapo heat shrink tubing

The prices of heat shrink tubing vary quite a bit but there are real outliers. For example, Rapid sells two types of 4....

0 comments posted 13yrs

posted by cheney

0 comments posted 13yrs posted by cheney

Nano Spring Cap/Batteries/Explosives

Stretched carbon nano tubes store energy at the same ratio to weight as liquid fuel. Considering the mass of the air or...

9 comments posted 13yrs

posted by BretCahill

9 comments posted 13yrs posted by BretCahill

Lead acetate batteries rechargeable?

Are such 12v batteries rechargeable? What type of small (alarm, motorcycle) batteries are rechargeable? What do I need...

18 comments posted 13yrs

posted by wolftracks

18 comments posted 13yrs posted by wolftracks

Driving higher voltages with p-type MOSFET

Hi guys: I'd like to control a 24Vdc load by sourcing with a p-type power MOSFET. I'= m driving the gate directly from...

28 comments posted 13yrs

posted by eromlignod1

28 comments posted 13yrs posted by eromlignod1

Non-Phool jellybean audio-frequency JFET

Trying to pick a JFET that's still being made with reasonable low noise characteristics for simple audio preamp type du...

35 comments posted 13yrs

posted by MyNameForward

35 comments posted 13yrs posted by MyNameForward

Replacement wall-wart help needed

This is a total "noob" question and I have done some searches but want to b= e sure before I go and purchase a replacem...

14 comments posted 13yrs

posted by telengard

14 comments posted 13yrs posted by telengard

P-Channel Complement to 2N7002

I remember this question coming up before, but can't remember if there was an answer... Is there a P-Channel Complement...

2 comments posted 13yrs

posted by To-Email-Use-The-Envelope-Icon

2 comments posted 13yrs posted by To-Email-Use-The-Envelope-Icon

high voltage capacitor charger - how to

Hi. I want to charge my capacitor bank with 72V-20A DC source. The idea is to store 1KW in this capacitor bank and then...

13 comments posted 13yrs

posted by nescafe

13 comments posted 13yrs posted by nescafe

comparators in IC 555

I've looked on the internet but no joy...there are two comapators inside an IC 555. What are these two comparators? Are...

27 comments posted 13yrs

posted by macmanus130

27 comments posted 13yrs posted by macmanus130

Low Tech Tips for Previous Wars

If you could go back in time, what would be the worst errors you could correct for various wars. These should be things...

69 comments posted 13yrs

posted by Bret_E_Cahill

69 comments posted 13yrs posted by Bret_E_Cahill

Trickle charge 12v batter with test load

I have a 12v "alarm" battery from The Shack that I bought about 3 years ago. It weighs about 5 pounds. I use it to oper...

7 comments posted 13yrs

posted by wolftracks

7 comments posted 13yrs posted by wolftracks

Spice Model Problems?

I'm honing my Spice modeling skills and need some suggestions of devices whose manufacturer-provided Spice model doesn'...

17 comments posted 13yrs

posted by To-Email-Use-The-Envelope-Icon

17 comments posted 13yrs posted by To-Email-Use-The-Envelope-Icon