Subj : 555 - love the comments!
To   : Barry Martin
From : Ed Vance
Date : Tue Dec 17 2024 20:21:19



> Hi Ed!

> So much for make a profit! <gg>

> Back then I built more with solid state -- I guess more because of the
> mechanical as didn't have to bore out holes for tube mounts -- easy to
> drill a small hole to mount a terminal strip or PC board.  Repairs were
> more tube-based as that's what needed repairing.

> That reminded me: Dad had a home-office combination so an intercom at 
> the office door and the kitchen.  Could hear street noise when the 
> volume was at talk level so turned down, but then of course had to 
> remember to turn back up to communicate.  Dad came up with the idea to 
> use a mercury switch as an on-off switch: upright to talk, lay sidewards
> to shut off.  No need to touch the volume!  (The intercom button by the 
> door went to a buzzer inside the house doorbell.))

>                      >                                 <
>                       >  BarryMartin3@MyMetronet.NET  <
>                      >                                 <

> ... ClientSez: This program says I have insignificant memory.
> --- MultiMail/Win32 v0.47
>  * wcECHO 4.2 = ILink: The Safe BBS * Bettendorf, IA

> --- QScan/PCB v1.20a / 01-0462
>  * Origin: ILink: CFBBS | cfbbs.no-ip.com (454:1/1)


I learned about Logic Gates from reading a Popular Electronics magazine in the
1970's.
For some reason AND, OR, NOR  and NAND Gates made sense to me.
So I bought a do-jig (can't recall the correct name) that let me wire TTL
circuits to see how they worked.
I remember playing with seven segment LED Displays (7447?), 555's/556's.
Never played with CMOS IC's 'cuz I was afraid that I would ZAP THEM and lose my
money I paid for those critters.
Yas, I am part Scotch and cheep at that.
Ed
--- SBBSecho 3.20-Linux
 * Origin: Ilink: CCO * capitolcityonline.net (454:1/105)

.