[Boatanchors] Reminiscing, my 8th Grade Science Fair Project

[Phil]

Hi All,

This is a copy of a message I sent to the Regen group.

WAY-WAY back when I was just a young sprout, I wasn't sure what I wanted 
to enter in the "Science Fair" (don't remember if that was the 
'official' name or not).

Well, just about everybody knew that I really had only one interest in 
life (and they weren't girls at that time ;-)  In fact, I had trouble 
keeping interested in most of the classes, though I managed to keep from 
bringing home any D's or F's (I'd have had a 'Parental Conference' if I 
had).

The science teacher suggested that I bring something "radio" and 
demonstrate/explain how it worked.

One of the things I thought of was taking my Signal Generator (think it 
was an Eico), a small AA5 receiver, mic and pre-amp and use it all as a 
mini broadcaster.  But that was a lot to lug to school on a bicycle, and 
I didn't think it would be a good demo.

Then I looked at a box of parts that I'd scrounged from some junked out 
radios, mostly AA5's.  When I parted out something (and I had a good 
source in the local TV/Radio shops), I saved EVERYTHING usable, 
including old resistors, capacitors, tube sockets etc.

Eureka!!  I'll build an AA5 (All American 5) receiver.  Only problem, 
funds were about non-existent, as was a suitable chassis (the one thing 
I didn't keep from parted out sets were the chassis and cabinet (if it 
had one).  Besides, it would be hard to make a suitable display that 
way, it might look like I'd just pulled a radio out of it's cabinet and 
not put any effort into it.

Then an old magazine article extolling the virtues of "breadboarding" 
projects lit up a lightbulb in my head.  I needed a breadboard, and I 
knew just where to find one.

Doing a couple uncalled for chores around the house followed by 
sweet-talking mom and I was the proud owner of one of her kitchen 
breadboards (think she was happy to be able to buy a new one anyway ;-)  
It wasn't pretty, but it was functional.

Taking my prize to the garage (which was my bedroom & shop) I gathered 
up all the needed parts, tube sockets, tubes, IF cans, output Xformer, 
tuning cap, speaker and so forth.

I think the only thing I bought was a Ferrite 'loopstick' for the 
antenna.  Anybody here remember those?  They were a small adjustable 
antenna coil with a short wire on it to act as the antenna.  They were 
often touted as a universal replacement for damaged loop antennas.  The 
board was too small for the large loop antennas that typically resided 
in the back of old sets.

After the donkey work was completed the real job began, laying out the 
entire collection of 'scrounged junque' in the order of signal flow.  I 
don't recall how long it took to assemble all of it, probably about a 
week as I was a very experienced builder by then. . .

The first time I plugged it in I stood back as I wasn't really sure what 
that Frankenstein Monster would do when hit with 110VAC!

SURPRISE, it worked!  Only problem is, with no natural chassis shielding 
etc it also oscillated to beat the band.  Whistles and squawks like you 
wouldn't believe.  But with some careful tweaking and rerouting of some 
wires I got it tamed down and it actually played music.

I then made up little paper labels briefly naming each stage, then 
borrowed mom's typewriter and made up a "poop sheet" describing what 
each stage did.

A couple days or so before the science fair the teacher asked me how it 
was coming.  I described it to her and she asked to see it.  When she 
saw it she was HORRIFIED that I intended to plug that thing in and 
display it!!!  Said if I wanted to enter it AND power it up I had to put 
a safety cover over it (this fits in with a recent discussion we had 
here on AC/DC power)!

To this day I have NO idea where dad got it, but he pulled a magic act 
and brought me a piece of clear plexiglass (or whatever the clear 
plastic of that time was) cut to the proper size to fit over it. A 
couple pieces of wood to cover the front and ends held the cover in place.

I think that was the ONLY time I ever got an "A+" on ANYTHING in school, 
lol.

-- 
73 From "The Beaconeer's Lair"
Phil, KO6BB
http://www.qsl.net/ko6bb/  (Web Page)

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