Cores, light bulb goes on ...

From: Chuck McManis <cmcmanis_at_mcmanis.com>
Date: Wed Apr 28 17:00:35 1999

At 06:40 PM 4/28/99 +0100, Tony wrote:
>Incidentally, I believe that the HP9100B core address driver is very
>simple. Just a emitter follower (with a low-ish emitter resistor)
>capacitively coupled to the address wire. This gives the required +ve and
>-ve spikes when the transistor turns on and off.

That's pretty clever, what size cap?

I = Cdv/dt on the cap would allow for an arbitrary spike.

I'll wire this up tonight. I bought some ferrite cores from a local surplus
shop on the reccomendation of one of the core manufacturers and they have
two very nice attributes:
        1) They are all consistent magnetically.
        2) Their magnetic properties are well characterized so I can
           relate theory to actual practice with fewer variables.

Note you those of you in school or headed there, even the most obscure
classes come in handy so PAY ATTENTION. :-)

--Chuck
Received on Wed Apr 28 1999 - 17:00:35 BST