"Of course I did," replied Bob. "You fellows had better get around bright and early this evening, because he said he'd be around right after supper.

I know I've got plenty of questions I want to ask him, and I guess you have, too."

"You can bet I have!" exclaimed Jimmy. "I want to ask him where he got that package of milk chocolate he had with him the last time I saw him. He gave me a piece, and believe me, it was about the best I've ever tasted."

"There you go again," exclaimed Herb, with a laugh, "always thinking of that stomach of yours. Don't you ever think of anything serious?"

"Serious?" echoed Jimmy. "It's a serious enough thing for me, where to get that milk chocolate. I've been in pretty nearly every candy store in town, but none of them seems to have anything quite so good."

By this time the boys had reached Main Street, and they parted for the time being, promising to get to Bob's house as soon as they could after supper.

The Layton family had hardly finished their evening meal when there came a ring at the doorbell, and Bob jumped up to admit the expected guest.

"h.e.l.lo, Mr. Brandon!" exclaimed Bob, as they both shook hands heartily.

"It seems great to see you again."

"I can say the same thing about you," replied Frank Brandon. "You're tanned like a life guard at Coney Island. I'll bet you haven't been far from salt water all summer."

"You're right there," smiled Bob. "I was in the water so much that it's a wonder I didn't turn into a fish. The whole bunch of us had a wonderful time of it."

"Good enough!" Brandon exclaimed, heartily. "Where's all the rest of your crowd this evening?"

"They'll be around soon now. I'm expecting them any minute. There's Joe's whistle now! I thought he'd be along soon."

As he finished speaking Joe came bounding up the porch two steps at a time, and he had hardly got inside and shaken hands with Brandon when Jimmy and Herb appeared together. There was great excitement while they exchanged greetings, and then they went into the parlor and were made welcome by Mr. and Mrs. Layton.

"It seems good to get back in this town again," said Brandon, in a voice that carried conviction. "You folks have made me so welcome ever since we became acquainted that it seems almost like my own home town."

"That's the way we want everybody to feel," smiled Mr. Layton. "Clintonia is a neighborly town, and we always do our best to make visitors feel at home."

"I hear you've done a good deal of traveling since you were here last,"

said Mrs. Layton.

"Yes, I had a little commission to execute for the government down in Miami," said Brandon. "A radio inspector is apt to be sent anywhere on short notice, you know."

"How is your cousin, Mr. Harvey, getting along?" asked Bob. "Has he got entirely over his experience of last summer, when Dan Ca.s.sey knocked him out and stole his money?"

"Oh, yes, he's all right now," responded Brandon. "I saw him only day before yesterday, and he couldn't get through talking about the way you fellows took charge of the station while he was down and out, and then got the money back afterward. That was mighty fine work, and you can believe both he and I are grateful to you for what you did."

"Oh, that wasn't much," disclaimed Bob. "Besides, he'd done so much for us that we owed him something in return."

"He didn't say anything about that," observed Brandon.

"I suppose that's the last thing in the world he would mention," laughed Joe. "But he gave us all kinds of stuff on radio, and even loaned us a practice set to get the code with."

"Don't forget about the motor boat," said Herb. "He was as generous with that as with everything else. We sure had some fine cruises in the old Sea Bird."

"That sounds like him, all right," admitted Brandon. "There's hardly anything you could ask him for that he wouldn't cheerfully give you. He told me that you fellows were getting to be regular sharps at the radio game. Are you building any sets at present?"

"You bet we are!" cried Bob. "Come on down to my workroom, and we'll show you what we're doing. We're working on a regular set this time."

"I'm with you," said Brandon, heartily. "Come ahead and let's see what you've got. I suppose you'll be giving me pointers pretty soon."

"Not for a little time yet, anyway," grinned Bob. "The government hasn't been after us yet begging us to take jobs in the radio department."

"You never can tell," replied Brandon. "There's a big demand for radio men these days, and we're getting some pretty young chaps in our division."

"We don't feel as though we'd much more than scratched the surface of radiophony yet," said Joe. "There's such an immense amount to be learned, and then there are new discoveries being made every day. It would take almost all a fellow's time just to keep up with new developments, let alone learn all the fundamentals."

"That will all come in time," said the radio inspector. "You're on the right road now, anyway, and traveling pretty fast. Say!" he exclaimed, a moment later, as he was ushered into the workroom and caught sight of the new set, which was partially completed. "You're certainly going into it pretty heavily this time, aren't you? I didn't imagine you were working up anything so elaborate."

"We thought we might as well make something pretty good while we were about it," said Bob. "It won't be much more work to make this set than a smaller one, and we expect to get a whole lot better results. Don't you think so yourself?"

"There's no doubt about it," agreed Mr. Brandon. "When you get this set finished, you ought to be able to catch pretty near anything that happens to be flying around. Let's see how you intend to hook things up."

The boys explained their ideas and methods in detail, while the radio man nodded appreciatively from time to time. Sometimes he interrupted to ask a question or make a suggestion, which was duly taken note of by the enthusiastic boys.

"There doesn't seem to be a whole lot that I can tell you," remarked Frank Brandon, after they had gone over everything in detail. "You seem to have thought it out very thoroughly already, and outside of the few minor things I've already told you, I can't think of much to suggest. It looks to me as though you'd have a pretty good set there when you get through.

"There's one tip I want to give you though," he went on. "And that is to be careful about your tuning. You've noticed, no doubt, that sometimes you get first-cla.s.s results, and then again the reception is so unsatisfactory that you are disgusted. Now in nine times out of ten the whole trouble is that you haven't tuned your receiver properly. You can't do the thing in a haphazard fashion and get the signals clearly. You know what Michelangelo said about 'trifles that make perfection.' Well, it's something like that in tuning your receiver.

"Now I see that in this receiver you have separate controls for the primary and secondary circuits. To tune in correctly you have to adjust both circuits to the wave length of the special signal that you are trying to get.

"First you start in with a tentative adjustment of the first primary. Fix it, let us say, for between a third and a half of its maximum value. I see that here the coupling between the primary and secondary is adjustable, so place it at maximum at the start. Of course you know that maximum means the position in which the windings are closest to each other.

"Then you fix up the secondary circuit for adjustment to the wave length, turning it slowly from minimum to maximum until you come to the point where the desired station is heard. When this is found, you again readjust the primary until you find the point of maximum loudness.

"Now you see the advantage of this double control. If an interfering station b.u.t.ts in, just decrease the coupling between primary and secondary and then tune again the two circuits. You can feel pretty sure of cutting out the interference and getting clearly just the station that you want."

"That's mighty good dope," said Bob. "I've had that trouble more than once and haven't been quite clear as to the best way of getting around it."

"Then too," went on the radio expert, "you must be careful in adjusting the tickler that gives the regenerative effect. Start in slowly by turning the control k.n.o.b toward the maximum. You'll soon strike a point where the signal will be loud and clear. Now when you've got to that point, don't overdo it. If you get too much regeneration, the quality of the notes becomes distorted and before you know it you have only a jumble. Let well enough alone is a good rule in tuning, as in many other things. When your coffee's sweet enough, another spoonful of sugar will only spoil it. Keep to the middle of the road. It isn't the loudest noise you want but the sweetest music.

"Be careful, too," he urged, "not to have too brilliant a filament. It's wholly unnecessary to have it at a white heat, and you don't want to burn it out any more quickly than you have to. You can save money in reducing the filament brightness by increasing the regeneration, which will make up for the loss of brilliancy.

"Now by keeping these things in mind," he concluded, "you'll be able to operate your set to the best advantage and get the satisfaction you are looking for."

"We certainly hope to, anyway," said Bob. "We've put a lot of work and quite a little money into this outfit, and we'd be mightily disappointed if we didn't get good results."

"There's not much doubt about that, I think," remarked Frank Brandon. "You ought to see some of the sets I come across! They look to be regular nightmares, but they get pa.s.sable results, anyway. Radio is certainly getting to be a country-wide craze. Only the other day I was at one of the big broadcasting stations, and the manager told me that they were actually having trouble to get performers, there is such a demand for them. They seem to be especially hard up for novelty acts--something out of the ordinary. People get tired of the same old programmes night after night."

"Say!" exclaimed Bob, struck by a sudden thought. "Why wouldn't that be just the thing for Larry when he gets a little better? He could do his bird imitations just as well as ever, and he could do it as well sitting in a chair, as far as that goes."

"Bob, you said something!" exclaimed Joe, slapping him on the back.

"That's just the kind of thing that would appeal to people, too. I'll bet he'd be a hit from the beginning."

"Who is Larry?" asked Mr. Brandon, curiously.

The excited boys told him all about their acquaintance with Larry and Tim up to the time of the almost fatal accident in the theater. Brandon listened attentively, and when they had finished sat thinking for several minutes.