Crystal Radio Gallery Page 1

Back in the days long before hi-tech devices of today, when kids got 5 cents a week allowance (or if you were lucky & rich, a dollar) the only affordable choice of owning your own radio in grammar school was a germanium crystal radio, or in the pre-1960s a galena crystal, (lead sulfide) crystal radio set. Some came pre-assembled, but finances required you build them from scratch or a kit. Most parents of the era preferred educational toys, so may have bought a crystal radio (xtal radio) kit or the parts for you. The decent pre-assembled portable germanium crystal radios can cost a whopping $1.29! At a 5 cents a week allowance, that could set one back a long time. It wasn't until the 8th grade I got a raise to a quarter a week. It wasn't that parents were incredibly cheap in those days, but just not as incredibly wasteful as mose americans have become today. We did better with less, rather than throwing a lot of money at something for no good reason.

The great thing about building crystal radios is their simplicity. There's very few parts & wiring needed to get a crystal radio running. No soldering required, in many cases you can just twist the wires together to make the radio in minutes. Just about anyone can make one with no previous technical knowledge.

Crystal radios require no batteries, household current, or solar cells. They're powered by the radio waves in the air themselves!

So what's the catch? Due to the radio's simplicity & limited power, they are not loud or as sensitive as modern radios. They usually aren't powerful enough to power a speaker, but there are a rare few that can dive a speaker to a moderate volume when tuned to a strong station. Typically you need to connect very sensitive high impedance headphones (rare these days) or in modern times, what's called crystal earphones or piezo electric earphones. Although most plans, kits, & assembled crystal radios require a single headphone, I highly recommend using 2 of them wired in parallel (one for each ear). I find the volume of 1 piezo earphone doesn't diminish at all by adding a second earphone to the earphone connection due to their extremely high impedance. If the radio has a resistor in parallel with the earphone connection, remove it if using 2 earphones. The volume, sensitivity, & selectivity will increase.

I find if you live in or near a city, no elaborate antenna & ground is needed to pick up 5 or 6 stations loud & clear enough. I would just clip the antenna connection to a metal bed spring or frame, metal lamp, furnace duct, phone line (yes, the phone will still work), refrigerator, any large metal object, or a couple of yards of wire dangling out a window... without a ground. On the simplest crystal radios strong stations may overlap with others, making reception of some weaker stations a little difficult. But I was always able to get 8-12 stations clear enough to be pleasant.