Tuesday, August 31, 2021

RF resistance data

 I'm putting this here so it does not get misplaced.

Monday, August 30, 2021

Consider the dualities. The opposites. What can we say about them? light - dark E field - H field particles at rest or in motion.

 Consider EMF, current, B and motion.

Can we have any of them without the other?

Suspend a wire in a H field and send a current threw it, it will try to move.

Suspend a wire in a H field and move the wire OR magnet, you will produce current in the wire.

Passing a current threw a wire produces a magnetic field. Can we have a magnetic field without current flow?

Consider the permanent magnet. It has closed loop currents in it structure which create the field.

Question: Can we have a "permanent E field"? Not a trick question so disregard a charged capacitor and the Lydel jar.

A bar magnet has a "permanent H field".

Can we have a "bar ????" with a permanent E field?

What if we melted a bar of wax and placed it in a strong E field and let it cool. Would the field effect the wax?

Can I use wax as the dielectric in a capacitor? Yes of course I can. Will it make a stronger capacitor? Yes it will. Again, what happens if I melt the wax and let it cool while holding a charge on the capacitor?

Hint: Consider the Electret Microphone.

 Notice the relationships in the right hand and left hand rules are all at 90 degrees. Also note one component is force/motion. With a generator we turn the armature to create current. With the motor the current causes the armature to spin. Can we have motion without a spinning armature? Consider the transformer. The motion in the primary is "current" flow. The motion in the secondary is also "current flow. 

 Note: In the beginning (when I was young) it was "H" field and "Cycles Per Seconds". Today they prefer "B" and "hertz" so I may at times use an unfamiliar term. I will even switch back and forth now and then.

LDO low voltage - pinned vs surface mount components

I was planning a single cell radio. The previous oscillator was looking good but will need a little more thought. In the mean time I am looking at the LDO for the single cell radio. My parts bin is fairly well stocked but I am having to decide between surface mount, pinned component or using 3 volts? (the original plan was 1 cell) This series of post show the options.

3 volts both pinned
2 volts both pinned.
1.5 volts 1 surface and 1 pinned.
2 volts both surface mount.
2 volt 1 pinned 1surface mount.
1.5 volts 1 surface 1 pinned.

So I can obtain the goal of a 1.5 volt LDO by using 1 surface mount and 1 pinned Jfet or I can move the goal and use 2 cells.