Bud Collyer was the voice of Superman, and did the voice up until the cartoons produced for TV in the 1960's. Mr. Collyer also hosted the game show "To Tell The Truth" and died in 1966.

When the series premeired in 1940, the story begins as we all know when Kal El was rocketed from the doomed Krypton as an infant. But one moment, he was a baby, the next he was an adult. No backstory of whether he arrived on earth as an infant or grown up.

Superman came on the scene for the first time saving the life of a man and a boy alone on an out-of-control streetcar. After they were saved, Superman told them that he wished to observe men -- at their best and at their worst -- the civilians suggested that Superman should look like ordinary men, and it was the boy who gave Superman the name Clark Kent. The man suggested that he become a newspaper reporter to best observe man.

In 1945, backstory began to be explored. At this point in the series, Superman said he arrived on Earth as an infant, crashed in a field, and was discovered by an unnamed couple who adopted him.

The difference is that Superman should've had his civilian name given to him by his adopted parents instead of by the first lives he saved in his career.

Didn't the radio show introduce Krytonite before the comics?

It was also the radio show (because radio dramas are better suited to dialogue than exposition) that first introduced the character of Jimmy Olsen.

And also Perry White.

As for the Kryptonite, it originally was part of a comic book story that never got published. Apparently the writers of the radio show saw it and liked it enough to incorporate it into their scripts.

I don't have the shows where Krpytonite debuted, but the shows where Kyptonite was put in a museum and got stolen by the Scarlett Widow. She broke it into four pieces and attempted to sell it to Superman's enemies for $1 million a piece.

A German megalomaniac stole one piece, had a Nazi scientist liquify it and inject it into the bloodstream of a Nazi soldier creating an "Atom Man". The other pieces were sold to arch criminals such as The Laugher and The Vulture. I forget who the 4th piece was sold to.

In a long saga, 3 of the 4 pieces were put to quick use until the Kryptonite was disposed of. Then the series took a long break from Kryptonite; giving the series a rest before returning to the subject. The Vulture was the last character in posession of Kryptonite.

Later, in 1947, The Laugher was near death in prison but before he died, he told a corrupted, bigotted, ex-governor where to get the 4th and last piece of Kryptonite known to exist on Earth. Here is where continuity and premises change. The Laugher named some criminal other than The Vulture has the Kryptonite. And in the next episode, the narrator recapped the last episode by saying The Laugher told of the Kryptonite he obtained by the Black Widow, not the Scarlett Widow.

This radio show did well by making references to incidents in previous chapters, however, The Laugher also has his own legacy of continutiy errors.

Laugher was sort of a forerunner to Luthor. When The Laugher learned of Superman and his connection to the Daily Planet, that Superman always manages to save his friends from death, The Laugher wanted only to break Superman's unbroken record. He even went to Superman and told him his plan. Since the Laugher was a master of alibis and his knowledge of Superman's morallity, he knew Superman couldn't do anything about him until after he strikes, and even then he would be able to lie his way out of it. Superman vowed he would prevent him from harming his friends.

On a trip to the woods, first the Laugher went after Perry White. Perry didn't die but he required hospitalization. Keep in mind, Superman is usually in Clark Kent mode for as long as there is no emergency and when there is a crisis and he is in the company of others, he makes lame excuses to separate himself and lame excuses when he returns. So while Superman intercepted a chopper already heading for a hospital, Laugher then went after Lois Lane. He took her out deer hunting, but his motive was to hunt Lois. Superman was still away, unaware of Lois' peril and would not be there in the nick of time. So at the moment of Laugher's triumph, his gun backfired; literally exploded in his face. I was waiting for any dialogue stating that it was Superman who sabotaged his gun in his promise to save his friends and take care of Laugher once and for all, which I thought was a very clever idea, but that explanation never came. So you have to conclude it was a legitamte accident.

It was winter at that time, Lois came to aide the Laugher (she and the rest of the Planet staff only knew his name under a different alias). The blast rendered him blind. He was overweight so Lois couldn't carry him. Then a blizzard rolled in and Lois couldn't find their way back to the cabin. Lost, the Laugher confessed his objective, but Lois still wanted to save him. He insisted she leave him behind. Frantic, Lois eventaully abandonned him as he was laughing all the way. Before she would freeze to death, Superman saved her. And the following dialog without saying he's dead, strongly suggested he was no more. If he wasn't dead, then his blindness would thwart any future threats to Perry, Lois and Jimmy's lives. Which I thought was a clever way of eliminating a menace without killing a character.

Not long after, the Laugher returned as one of the Kryptonite purchasers, not blind and no specific references to his past altercations with Superman only to wind up dying locked in prison.

There are no known recordings of the episodes where Kryptonite debuted. This is hardly uncommon with radio shows from the Thirties and Forties. I believe that the scripts were published and made available for sale. Though there's a good possibility that they're out of print, so you might have to check Ebay.

I've now reached the episodes "The Superman Rocket" where Superman again rehashes his origin story.

Although little embellishment is made on his foster family, it is slipped a couple of times that it is the Kent farm, which again contradicts this series' initial premise that a civilian man and boy, the first lives he saved as Superman, gave him his human alias Clark Kent.

The differences this time is that his adopted hometown is Centerville, Iowa as opposed to the contemporary Smallville (Kansas?)

Batman and Robin have made several guest appearances although I have yet to hear whether they also live in Metropolis. Gotham City is either not established as their home field (on this radio series), or merely gone unmentioned.

The series has hinted that Bruce is rich by throwing out the word "playboy" once and when a wrongfully accused Robin was charged with burglary, Wayne says "I have plenty of money (so why should Robin steal?)" He has yet to achieve the full-time moniker of Millionaire Bruce Wayne or Millionaire Playboy Bruce Wayne.

Superman carries a lot of people, good and bad alike, in flight. When Superman flies at near lightning speeds, I would think an unprotected human should suffer from cold, especially in cold weather, and wind burn, espescially in the eyes.

In 1947 or 1948, there was a story of a crook who broke into Kent's apartment, discovered a secret closet and found a spare Superman suit. He got fatally wounded in the escape and died short of telling his boss whose apartment he found the suit. The boss would send an accomplice to go door-to-door as an inspector for apartment painting to find the apt with a secret closet to identify Superman's double identity.

Kent, along with Bruce Wayne, kept distracting the faux-painter by various subterfuges, until finally, Kent had no choice but to hide the closet by blocking it with bricks and mortar.

About a year or two later, another robber burgles Kent's apartment and also discovers a secret closet and Superman's spare suit. Did Kent decide to reuse that closet after the heat was off from the last time? Did he create a different one? Or did the writers forget or ignore the previous lesson Kent was supposed to have learned about the accidental discovery of his secret closet?

Also, the Scarlett Widow has returned from the dead. The writers didn't forget about her death, but made some throwaway line for Superman by having him say "I thought she had died."

Her last appearance had her die IIRC under debris either from an explosion or some other structural collapse but not before she could give her surviving partner information. I don't recall dialog pronouncing her dead, but that was the impression the audience was left.

As I mentioned in a previous post, in a follow-up Kryptonite story, the narrator made mention of The Laugher purchasing a fragment of Kryptonite from the "Black" Widow, when it was in fact the "Scarlett" Widow.

Regarding Kryptonite, I do know that it was brought into the radio show to cover up for Bud Collyer being unavailable (I don't remember if he was sick or what) for a while, and all you heard was Superman groaning in agony for several episodes (someone else providing the sounds, obviously) until Mr. Collyer came back. I believe that Atoman and Batman and Robin were introduced to the radio show during this storyline.

I don't remember the issue #, but an anniversary issue of World's Finest I had when I was younger (ie, somewhere in the late-70's to mid-80's) explained all this in an article inside the front or back cover, and the Atoman character was brought into the comic during that issue.
Unfortunately, I don't have that comic anymore, or I'd check my facts.

Oh, and the costume given to Atoman in the comic was the same costume that belonged to a previous DC character that was named (I think) Powerman. The character (Powerman, not Atoman) was actually a robot created by Batman.