The Old Timer Gives a Safety Lecture, December 1960 Radio-Electronics

Jack Darr authored many pieces for Radio-Electronics magazine. Most were monthly columns dealing with servicing and troubleshooting. He also published a dozen or so book on electronics, like Eliminating Man-Made Interference, Servicing Unique Electronic Apparatus, Transistor Audio Amplifiers, and How to Test Almost Everything Electronic. Release dates range from the 1960s through 2021. Mr. Darr has been doing this for a long time! This article on safety "best practices" when working on electrical and electronics equipment appeared in a 1960 issue of Radio-Electronics. A lot of the danger back in the day was attributable to poor design methods that did not properly isolate the line voltage from exposed metallic surfaces. That included the chassis onto and into which components were installed, hookup wires, and shafts for potentiometers, tuning capacitors, and switches. The plugs on supply cords were not polarized, so that there was no guarantee that the "hot" side would not be connected directly to the chassis, unless an isolation transformer was included at the input. As can be seen in Figure 1, most receptacles had no safety ground connection. Most people are not aware that touching the "neutral" wire on an AC line can shock you if you happened to provide a lower resistance path to ground than the circuit run back to the house breaker or fuse panel.

The Old Timer Gives a Safety Lecture

It's the little (?) things (like the low voltage in a TV and exposed wires) that are dangerous.

The Old-Timer came in the back door of the shop, whistling "Colonel Bogey" very softly. He smiled as he heard loud voices from the small back room he had donated for the Ham Club the Young Ham had organized. The smile turned into a full-sized grin as he saw the new sign the Young Ham had made a few days before. It was simply two colored pictures clipped from magazines: a luscious ham and a fearsome looking spiked club, pasted to a board.

The voices rose as he neared the door. "No, Eddie, look here now! You're not getting any rf out into the load because you haven't got enough coupling! See? This coil has got to go over a little more!"

"Yes, but not near enough," said the first speaker, the Young Ham. "A little ol' yellow glow like that ain't 50 watts, is it? You oughta get a bright white on that bulb!"

The Old-Timer glanced through the doorway at the two boys. They were bent over a piece of equipment at the far end of the bench. The smile froze on his face as he saw the tangle of wires trailing down the bench. Quietly, unheard in the continuing argument, he reached for the master switch he had insisted they install after they had left the lights on all night a few times. He snapped it off, which brought a simultaneous roar from both boys. "Hey! What'd you do now?" They looked up and saw him leaning against the side of the door. The look on his face brought them both upright with apprehension written on their faces.

He reached for the master switch ...

Fig. 1 - A pair of ac-dc sets may have full line voltage between the chassis.

Never touch an "outside antenna" lead of a radio or TV - RF Cafe

Fig. 2 - Never touch an "outside antenna" lead of a radio or TV when standing on the ground unless the set's plug is out of the socket.

"All right," said the Old-Timer grimly, pointing to the mess of wires on the bench. "What'd I tell you about that?"

"That" consisted of: (a) approximately 3 feet of slightly dilapidated line cord with a molded plug, connected to the ac outlet; (b) 6 feet of plastic-insulated bell wire connected to the other end of the line cord; followed by (c) 3 feet more of line cord terminating at the power transformer of the home-made power supply. All the connections were twisted (none too tightly) and all were completely innocent of tape or covering of any kind. From the output terminal board of the power supply, several similar leads went to the small transmitter the boys had been working on. These were also haywired (twisted to screws, twisted together, or simply twisted) and sans insulation or tape.

The Young Ham gulped and hung his head. The Old-Timer snorted and glared at him.

"Dang it all, now you know better'n that! I'll swear some people git up bright and early, looks like you just got up early! If I've told you once about them haywire hookups, I've told you a thousand times and this is the last one. From now on, use a little common sense around this stuff. I know I pay Dick a heck of a lot of money for fire insurance on this place, but I don't want none of it back. There's new line cord and stuff all over this place. Why didn't you use some of it?"

"Well, we were just trying it out," said the Young Ham sheepishly. "We didn't want to waste any new stuff on it until we knew whether it'd work."

"Look, Jughead," fumed the Old-Timer. "I don't care if it ain't for but 10 seconds. Don't ever let me catch you hookin' up a Fireman's Friend like that again! Why, a new plug and line cord wouldn't cost over 30 cents. My gosh, I'd rather give you th' stuff! Did I ever fuss at you guys about usin' stuff like that?"

"No," admitted the Young Ham, "but I've seen you usin' things like that in the shop. Hooking up record players an' things."

"Hah? Oh, you mean th' Fool-Killer? Come here just a dad-burned minute!" He chased them up the long hall ahead of him, into the service shop. He picked up a 5-foot piece of POSJ cord from a hook above the bench. One end was fitted with a bulky plug, the other terminated in two rubber-covered test clips. "Now, is this what you're talking about?"

"Well, Junior, there's a wee mite of difference," said the Old-Timer, shoving the plug under the boy's nose. "Look here. Do you notice anything unusual about that plug?"

"Well?" demanded the Old-Timer. "Doesn't that spell anything to you? There's a pair of nice little 2-amp fast-blow fuses in there, one on each side of the line. If I do get a short in anything, or let the clips touch accidentally, one of 'em pops out and everything's pretty safe - as far as the fire hazard is concerned. That ain't sayin' anything about th' shock hazard, though! You just gotta use a little common sense with it! Dang it, do you know how close Eddie's elbow was to one of them frazzly connections you had in there? About 2 inches! You were so busy arguin' about that transmitter you didn't even notice it. Those frazzlin' B-plus wires with about 500 volts on 'em weren't over a few inches away! Y'know, sometimes I wonder how you guys managed to get as old as you are."

"Junior!" said the Old-Timer, sternly. "You weren't watching me, and I stood there for a minute or so before I noticed what you were doing. Why, I saw both of you darn near get electrocuted three or four times! I was so scared that I like to never found that switch. Now you listen to me, young sprouts. From this moment on, every time you hook up anything like that around here, you take the proper precautions, and that means making sure that all your connections are safe, well insulated and tight! Then, you can go ahead and argue till you're blue in th' face about your loading procedure and you'll be safe. But, if I ever find another haywire hookup like that one around here, out you go, the whole gang of you, while you're still alive. Get me?"

The boys looked at the fire flashing from the Old-Timer's eyes and decided that he really meant what he was saying, so they surrendered gracefully. "OK, we'll be good, from now on," said the Young Ham. Eddie nodded agreement.

"You'd better be," said the Old-Timer, with a return of his normal good humor. "I'll be danged if I want to take the trouble to break in any more young squirts around here, to say nothin' of all th' money I'd have to spend for flowers. No, young fellers, I know that you guys feel like you know quite a bit about electricity and things, but that's the one thing you never ought to do in th' electronics business: get cocksure! Y' know, you can always tell th' difference between an old-timer and a new hand just fresh out of radio school: ask 'em both the same question. Th' young dude right out of school will pop right back at you with a positive answer; the more experienced man will always say: 'Well, I don't know right now. Let's check it and see!' Time you get to the point where you realize you don't actually know nothin' about this bewildering business, then you're gettin' to be a pretty good radio man!"

"I sure am thirsty," piped up the Young Ham, nudging Eddie, who dutifully echoed, "Me, too,"

"All right, you human sponges, come on," growled the Old-Timer in mock anger. "Let's go gitta cuppa cawfee. But if you think you're gonna take my mind off the lecture you're gonna get, you're mistaken! You've both earned a good chewin' and you're gonna get it!" He led the way out the back door, down the alley and into the drugstore.

"Speakin' of hot stuff, which you'd probably rather I wouldn't but I'm goin' to anyhow," said the Old-Timer, stirring briskly, "now you're gonna get the rest of that lecture you got comin'. Didn't I see you workin' on two ac-dc's at the same time on the radio end of th' bench ?"

"Yes," replied the Young Ham. "One of 'em needed a filter capacitor and I was cooking the other one after I changed the rectifier, to see if there was any more trouble in it." He had a strange gleam in his eye, but the Old-Timer pursued the questioning, not noticing.

"Well and good," said the Old-Timer. "But I didn't tell you to work on two ac-dc's at the same time on the same end of the bench. Tell me, how's the ac line connected to an ac-dc set?"

"Yep. Now, if you got two chassis with this kind of line connections, both of 'em out of th' box with the chassis exposed, what's the ac potential between them?"

"Zero?" The Old-Timer's left eyebrow shot up, a trick he had practiced for many a year.

"Zero!" repeated the Young Ham firmly. "Nyaaa! You were going to catch me, weren't you? I actually remembered what you told me about that. So, I checked between the two chassis with the little neon checker (Fig. 1) and turned the plug around on one of 'em! Zero voltage! Also made sure both chassis were on the ground side of the line.

"Well, I'll be cow-kicked!" said the Old-Timer, shaking his head in amazement. "You got me, f'ar and squ'ar! I'll swear, I thought that had gone in one ear and right out the other in that non-resonant cavity you use for a head! My, my! I just can't git over it." He shook his head solemnly. "Congratulations, young feller, Just for that, I'll buy th' coffee!"

"You might not have known it, but you were going to anyhow." The Young Ham grinned. "I'm broke."

"This is unusual?" said the Old-Timer. "Well, sir, I'm glad you thought of that, though. It's sure a good habit when you're workin' around stuff like that. You know how I found out about it, don't you?"

"Yes, sir!" said the Young Ham. "And you got reminded of it just last week, when I had that portable sitting on my end of the bench, and you backed into it while you were moving that ac-dc TV set! Goodness, such language!"

"Well, I was mostly mad at myself," admitted the Old-Timer. "Us old fools ought to remember them things automatically, and we do, most of th' time, but we still git caught now and then. That's just th' reason I yowl at you guys so much about bein' careful with electricity. Workin' with it all th' time, you're gonna get a plenty of shocks accidentally, even with good habits. There's only one way to stay alive in this business, and that's to be careful, dern careful! And that's somethin' else you've got to do for yourself. There sure ain't nobody goin' to do it for you!"

'Nother thing, while you're workin' with a transmitter like you were a while ago. Don't ever let anybody else handle the key. You do it yourself! If you're the one makin' the adjustments, you do th' keyin'; it's a heck of a lot safer! I 'member once durin' th" War, while I was with the Air Force. Three or four of us was arguin' about a transmitter, just exactly like you were just now. All of a sudden one feller keyed the thing to illustrate a point he was tryin' to make. Only trouble, I happened to be leanin' on the final plate caps with my elbow!"

"Well, not too much, but I'll tell you one thing. I was the only man that left the ground that day on that field without takeoff clearance from th' tower! I got darn near as much altitude as some of the kay-dets! Th' moral of that is: if someone is workin' on a piece of equipment, stay clear of it. If you're workin 'on it, make everybody else stay clear and always look to see that everything's safe before you mash that button. Saves a lot of trouble!"

The Old-Timer paid for the coffee, as usual, and they trooped out the back door and across the alley to the shop. Lighting his pipe, he perched on the end of the bench and continued the discussion.

"Y'know, there's lots of what you might call 'everyday' hazards that we run into that we don't really pay enough attention to. F'rinstance, even you know enough not to go outdoors, stand on the ground, and try to hang up an antenna wire that's already tied to an ac-dc radio in th' house (Fig. 2). You'd be surprised how many folks don't, though! Way I look at it, that oughta be part of our job; to kinda warn the customers about such hazards."

"Yeah," agreed the Young Ham, "I've heard you tell lots of 'em about that kind of stuff. I hope they paid attention to it."

"So do I, Junior," said the Old-Timer soberly. "If all th' techs would take a little time to warn their customers about some of the hazards, maybe we wouldn't be hear-in' about so many people gettin' electrocuted by touchin' a TV set and stuff at the same time. While we're on th' subject, that's one thing I want you to promise me you'll always remember to do: never let a set git out of here in such a shape that it could hurt anybody. I'm pretty proud of you so far. You've been dern good about it. Keep it up."

"You mean like always putting the backs back on little ac-dc radios and checking the line cords for bare wires, and so on?" asked the Young Ham.

"That's it," said the Old-Timer. "And if the radios should have a metal cabinet, be dern sure that the chassis is isolated from that cabinet, like it ought to be. Remember the little set we found with the chassis shorted to the cabinet 'cause some kid had poked a metal bobby pin into it? And, most especially, watch out for these metal-cased portable TV's with the hot chassis. Pretty near all of 'em are provided with some kind of insulation between chassis and cabinet, but be awful careful to check those insulators. I've found several of 'em chewed out and shorted: found one set shorted to the case cause some sloppy-joe had dribbled a big hunk of solder down the chassis!"

"Tell you one more," said the Old-Timer, relighting his pipe. "You know the little isolating networks in the antenna connection? Couple of little capacitors in series? I found one only day 'fore yesterday, where some jerk had shorted those out! Don't know who did it, but they were shorted out beautifully. Tied a piece of wire across 'em! I do know what the result was: he managed to burn out the balun coil on th' tuner doin' it! It was one of those stinkers, too. I had the heck of a time gettin' it back in that tight place. Wish they'd put 'em on the outside!"

"I could stand a little of that," said the Old-Timer. "T'ain't too easy as it is. No kiddin', though, that's something you want to watch out for. You can git th' infernal waddin' knocked out of you if you happen to get hold of the lead-in with one hand and touch the chassis with the other! Don't ask me how I found that one out, either. I remember once I was squattin' down behind a TV set and got between antenna and chassis: I bounced off, hit th' wall and bounced right back onto th' TV set again, which promptly bounced me right back to th' wall, and so on! I'll tell you, when I finally stopped bouncin', I felt like the oldest punching bag in Johannsen's gym!"

"Yep," said the Old-Timer ruefully. "Like before, I was mad at myself for bein' so careless, and that's the worst kind! Seriously, though, you wanna watch out for that kind of stuff. I was readin' an article in a science magazine a while ago, and the doctor who wrote it told how much current it took to be fatal. Guess how much it was."

"Nope," said the Old-Timer, soberly. "Eleven milliamperes! That ain't much, is it? A 50L6 draws a heck of a lot more'n that: so, always remember that figure! If you get caught by an electric current so that that amount of current flows through your heart, you're off the air for good. So, that's one of the reasons for this old savin' about 'one hand in your pocket.' Although a shock any place is bad, I believe it's worse if you get it from 'hand to hand,' you might say, so that the current path is through your chest. You can git pretty bad shocked say from fingertip to elbow, and although it'll hurt like fury, it wouldn't be as bad as if it was from arm-to arm.

"That's the reason I always wear thick rubber-soled shoes, and keep 'em dry whenever I'm foolin' around anything. Long as you ain't grounded, you ain't in near' as much danger.

"I might give you another word on th' matter, too. You notice everybody seems to be pretty scared of the high voltage in a TV set, even lots of guys who should know better. Well, that stuff isn't near as dangerous as th' 300 volts or so in what we laughingly refer to as the 'low-voltage supply.' Actually, th' low-voltage'll kill you a lot quickern th' high voltage. Best way, of course, is to keep off of both of 'em!"

"Right," assented the Young Ham. "Well, sir, I'll give you one last word, while I'm at it: you seen a darn good example of it this morning, right here. Regardless of how much you ,know about electricity, and how skillful you are, a well insulated and properly installed circuit won't bite you. So, the best thing for any of us to do is use the most useful remedy - good old common sense!"

The Old Timer Gives a Safety LectureDecember 1960 Radio-Electronics

The Old Timer Gives a Safety Lecture

The Old Timer Gives a Safety Lecture
December 1960 Radio-Electronics