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Friday, October 2, 2009

The Case for the “Proof”

Primarily on the radio side, but applicable to TV, too, audio equipment performance tests (the “proof”) have gone the way of the west. About all that’s left now are the spectrum occupancy measurements required of AM stations to ensure that they are operating within the NRSC2 mask.

Every time I write that, I envision a mask with two eyeholes and sidebands escaping through them. Regardless, there aren’t other measurements required. Or are there? Have you changed transmitters? Maybe other audio gear that would be in the signal chain for measurement during a proof? Change of transmitter or studio location or a new STL?

Any of those actually imply the need for a new spectrum occupancy proof – AM, FM, or TV. (see reprint of applicable rules, below) That proof isn't the full-blown set of tests – frequency response, distortion, AM noise (AM and FM) FM noise (FM) stereo separation (FM), all of the crosstalk measurements and the other “lesser-knowns,” but running what used to be a full proof can really pay off.
The proof can be one heck of a tool for making sure you’re getting the most out of the station. All sorts of crazy things make themselves visible during a proof. True, most are undesirable and may well leave you scratching your head or mumbling but if it gives you a chance to ferret out the culprits and drive a stake through their collector, it’s worth it.

A couple of examples: Once found a subsonic rumble that was making its way onto an AM. The doggoned thing actually tracked the audio in volume so that when audio was low, you really couldn’t hear it. But with higher levels, it was there, eating up modulation and standing out as a nonharmonic tone it whatever music was bellowing out. By first threatening then changing the power supply caps in the audio console we sent the tone packing.

By the way, this type of problem makes leaving all equipment in the chain a good idea. You’ll never see what that compressor is causing if you patch around it. Take it out for the real measurements if you want to but at least look at the mod monitor on a scope with all processing in. When you see that 120Hz floating on the audio, it’s a dead giveaway of a problem that’s affecting your sound.

Another time, we saw a change in VSWR with modulation. This often is caused by poor bandwidth - AM or FM. This time, though, it was 100% modulation that a capacitor in one of the ATU’s on a DA didn’t like. It’d do a “soft breakdown” (if there is such a thing), meaning the value changed with 10 seconds or so of 100% modulation. The impedance of that tower’s ATU changed. Incidentally, that meant the pattern changed, too. Now, we didn’t see it in normal operation – heck, even Eddie and Alex didn’t hold a note at 100% for 10 seconds, but we at least got the problem out of the way.

Yes, these are strange ones – unlikely to happen. But there are other equally challenging anomalies that will reveal themselves if you give them a chance. Don’t like the middle of the night? If you don’t have to run a proof, go on backup and run the main it into a dummy – just to see. It won’t find things like that VSWR problem above but will allow you to spot a lot of others. And you won't be able to use the whole signal chain unless you have redundancy there, too, but regardless, you'll know that what you did check is OK or needs looking after.

Short cuts: There are a couple of so-called short cuts. 1) Use pink noise and a spectrum analyzer (you can use an audio spectrum analyzer on the output of the mod monitor) for frequency response. You’ll see the preemphasis plain as day. 2) Use the mod monitors for noise measurements. 3) Record short segments of distortion tones onto a computer with a good sound card. Afterward, there are a number of programs which can show you harmonic distortion in both level and percentage. 4) If you’re using a two-way line like a DS-1, you can turn the signal around at the transmitter and get good information sent back to you for some of the measurements. Don’t, however, try to measure AM or FM noise at the studio through an RF amp. Your AM noise will be beautiful because of the limiter in the RF amp. Your FM noise will vary based on the noise that may be added by the amp.
Current Rules:
Subpart H_Rules Applicable to All Broadcast Stations Sec. 73.1590
Equipment performance measurements.
(a) The licensee of each AM, FM, TV and Class A TV station, except licensees of Class D non-commercial educational FM stations authorized to operate with 10 watts or less output power, must make equipment performance measurements for each main transmitter as follows:[[Page 290]]
(1) Upon initial installation of a new or replacement main transmitter.
(2) Upon modification of an existing transmitter made under the provisions of Sec. 73.1690, Modification of transmission systems, and specified therein.
(3) Installation of AM stereophonic transmission equipment pursuant to Sec. 73.128.
(4) Installation of FM subcarrier or stereophonic transmission equipment pursuant to Sec. 73.295, Sec. 73.297, Sec. 73.593 or Sec. 73.597.
(5) Installation of TV stereophonic or subcarrier transmission equipment pursuant to Sec. Sec. 73.669 and 73.1690.
(6) Annually, for AM stations, with not more than 14 months between measurements.
(7) When required by other provisions of the rules or the station license.
(b) Measurements for spurious and harmonic emissions must be made to show compliance with the transmission system requirements of Sec. 73.44 for AM stations; Sec. 73.317 for FM stations and Sec. 73.687 for TV stations. Measurements must be made under all conditions of modulation expected to be encountered by the station whether transmitting monophonic or stereophonic programs and providing subsidiary communications services.
(c) TV visual equipment performance measurements must be made with the equipment adjusted for normal program operation at the transmitter antenna sampling port to yield the following information:
(1) Field strength or voltage of the lower side-band for a modulating frequency of 1.25 MHz or greater, (including 3.58 MHz for color), and of the upper side-band for a modulating frequency of 4.75 MHz or greater.
(2) Data showing that the waveform of the transmitted signal conforms to that specified by the standards for TV transmissions.
(3) Photographs of a test pattern taken from a receiver or monitor connected to the transmitter output.
(4) Data showing envelope delay characteristics of the radiated signal.
(5) Data showing the attenuation of spurious and harmonic radiation, if, after type acceptance, any changes have been made in the transmitter or associated equipment (filters, multiplexer, etc.) which could cause changes in its radiation products.
(d) The data required by paragraphs (b) and (c) of this section, together with a description of the equipment and procedure used in making the measurements, signed and dated by the qualified person(s) making the measurements, must be kept on file at the transmitter or remote control point for a period of 2 years, and on request must be made available during that time to duly authorized representatives of the FCC.[47 FR 8589, Mar. 1, 1982, as amended at 51 FR 18450, May 20, 1986; 65 FR 30004, May 10, 2000]

Wednesday, September 9, 2009

Where are the Leaders?

Yes, the economy's bad. "Let's not make waves." Yes, many of us are far from top management. "Just keep my head down and fly under the radar." Wow! A great way to keep a job, maybe, but what does it really do for you or the company? Not much. Long before the economic downturn, leaders disappeared at alarming rates. Workers became more and more passive, carrying out orders from above. And those "above" were busy carrying out orders of the "top." No thinking, just robotic, rote performance. No wonder the business is stale. And no wonder there are no new ideas. It's not just fear of job loss or of being branded a renegade. It's that no one knows how to lead. So why's that? How about no one's really been given any responsibility. Home, school, work, everyone gets a pass. What I mean is that they get correction instead of guidance. Lists and procedures instead of goals and opportunities. They will look down on a new idea and promote conformity - their conformity - in the home, at school, and in the workplace. Worse still, they can't get to you fast enough with "help." Their help; their solutions; their thinking. Follow that with a reluctance to rate performance, and you have a couple of generations used to being bailed out...used to following. So, are you a leader? Are you willing to go out on a limb for a good idea? Ready to gather people around your thinking in order to produce a better product or sell more spots or cut the costs on a remote broadcast? Or do you wait for the thinking of others. It's a sad thing, going along day to day waiting for requests from above, below or to the side, offered along with suggestions on how to accomplish someone else's goals. Just as sad to be doing so out of fear. But there's a way out. Be a leader. Sounds simple enough. Get yourself a "Leader" button, pin it on and start marching around. Or you could try this:
  • Engage in conversation and think about what other people are saying
  • Listen to the problems
  • Evaluate your own problems or challenges
  • Devise a solution
  • Write it down, concisely, so you can explain it to others
  • Look at the solution logically. If it really works, great. If there are hitches, write them down, too
  • When you're talking to those that can "approve" your idea, work your way into it slowly. With luck, the subject will be brought up by the other party. Be ready with the :30 - the "elevator speech" that sells in your idea
  • You'll get asked for more. Be prepared with backup
  • Make that backup honest. Up front! If there are flaws or elements that need to be worked out, put them out there along with a solution.
  • Go back to others whose help you will need and sell the idea in. No doubt, the "approver" will seek counsel from at least one of them
  • When the go-ahead comes down, move! Have a plan of attack and execute
  • Keep people apprised of the status
  • Once executed, rate it fairly and make sure everyone knows
  • Do it all with enthusiasm

A lot of work? Sure, but that's leading. Once you get one in the bag, others come more easily and that easing is exponential. It becomes habit.

Leadership isn't being the loudest voice at the table. It's creating or recognizing good ideas, being willing to embrace them then taking the baton and running with it.

Wednesday, August 5, 2009 Makes Everyone a PRO.

Today's gear - hardware and software - makes everyone a pro, right? At least that's what the marketing for manufacturers of most cameras, workflow systems, storage systems and editing software will tell you. My take is a little different: Today's gear makes everyone an amateur. Yeah, a pretty broad brush, but look around. Watch a network or cable channel - see if they can go a half hour with an on-air refocus, accidental zoom, jump cut, closed mic...good luck. I know, I know: look at what's going on on the screen. So much that it's impossible for a production team to manage it all. Well, nobody cares about that part. They care about the content. That's another interesting point: if it is about the content, the way it's presented, production warts and all, shouldn't matter. Maybe so, but does that mean we should all sink to the amateur level just because that clip fed via satellite phone has such poor resolution? Or should we be trying a little harder to up the quality of production. An industry friend called awhile back and asked me for a definition. "What does 'broadcast quality' mean?" I don't have an answer anymore. It is about the content and if that means a YouTube clip makes it to air, fine. But if that clip is surrounded by sloppiness, well, that's not quite so good. But how to define broadcast quality? It's impossible. What to do? How about paying a little more attention to quality. Many techs I know will bust their hump to wring an additional 2 kilohertz of audio response out of a device - if you let them. Most editors will gladly work through a jump cut if they can. They have the pride. It'd be great if that ethic were more pervasive. Then it might be true - the amateurs may really try to emulate the quality that pros put out. Hey! It could happen.

Friday, July 31, 2009

A Little Knowledge...

I was forwarded a complaint by someone living in the blanket area of one of my client stations. Seems we were 5x9 on their $10 house phone. We constructed a small filter and sent it on to them. A couple of days later, a call was forwarded to me. Seems the wife had been told by the husband that she'd better not install it or she could get killed. According to her, he knew "...a lot about electricity and he noticed that the box had over a thousand volts in it, maybe two thousand." Well, he knew enough about opening a device but, apparently, didn't know much about reading capacitors. Those good old .01 @1000v discs would have done their job but may not get the chance. I tried to explain working voltage but don't know that I got through. It brought to mind the statement, "A Little Knowledge is Dangerous." We've all experienced some of these situations. In the "not so dangerous" category is the jock who decides that he can bring in a bunch of Y adapters and series them up so that 4 people can plug headphones into one board phones output. With luck, a fuse will blow or the chip will shut down and there's not a lot of damage done. Then again, they can get more dangerous - like the guys who want to adjust the audio processor on their own. I have seen some so far "gone" that the only way to correct the problem is to reset to the defaults and start over. One friend once very carefully built a gonculator (with respect to Hogan's Heroes). It had 4 pots and two screwdriver adjustments. He labeled it the (call letters) Audio Processor. It had Belden going in and out. The pots had calibrated scales and there were labels above the screwdriver adjustments...labels like: Male Voice Enhancer Depth, and Sibilance Compression. Others were labeled with even more esoteric names which slip my mind. He installed the box in a rack and put a plexiglas cover on it, held down with screws. Now, although the box wasn't in line and did nothing, it was regularly the object of adjustment. In fact, one jock in particular became irate when another one "misadjusted" the box, screwing up his air voice. It was weeks before my friend finally let them all know what they were - or weren't - doing. Actually, those adjustments did nothing and, therefore, the "little knowledge" had little danger. Then comes this one: The DA is out. The antenna monitor is fine but the monitoring points are off. After you examine and cross examine, someone, maybe even the GM, fesses up. The monitor was reading wrong and the started cranking till they got it close. Out at the tower, you replace the toroid with the shorted turn, return the phasor coils to their Sharpie positions and, son of a gun, it's back in tolerance. I don't need to go on. You can all add others - most probably more traumatic than these. Question is, how do you convince folks to call first? If you have the answer, open an office and just sell that answer. You'll make millions.

Friday, July 17, 2009

You Think that 7805 Will Heal Itself?

They Never Heal! I seldom beg…but I have to this time. Anyone who’s doing field service…please...when you pull a bad component, throw it out – or at least find a bucket and clearly label it, “Bad Parts I’m Hoping Will Heal.” How many times have you entered a site for the first time to find drawers full of components with solder on them (as if they’ve been removed from a circuit) or labeled, “removed” or “E-B short” or just “bad”. Here’s what I’ve found. No bad part has ever healed. Fuses stay blown. Transistors stay shorted and open diodes are open forever. So get rid of them. And the ones that can be fixed…send the choke off and have it rewound or get rid of it. What a time waster to have to re-declare a MOSFET DOA so that you don’t install it and find that the same symptom prevails, or worse, new ones pop up. It’s a simple request. Throw them out. If you really want to keep them, put them in that bucket or nail them to a piece of wood or curl their leads to make cute little bugs. It’ll save the owner countless billed hours and you lots of headaches. One important note: If there’s a possibility of an insurance claim, document every part failure and replacement and hang on to all of the parts until the claim is settled. If you want to take things one step further, do a real inventory. Right. Count ‘em all. First, you’ll be surprised what you have for emergencies and second, it makes emergency repairs a lot easier and faster. Of course, it helps to sort and store everything so it can be found, otherwise, it’s all for nothing. Now, the problem with all of this is that there’s never enough time – and ask the average owner if he/she’ll approve overtime so that you can take inventory and catalog, and the answer probably will be no. Maybe you can play back the part above about saving money on future repairs. That might get you an OK. Then again, maybe not.

Saturday, July 11, 2009

Music and Radio - Friends at War

The music business continues in the doldrums as broadcast radio repeats its slide in listenership and revenue. One would think that two businesses whose relationship has been symbiotic for over 70 years would be all over one another to boost collective growth. Well, think again. First, the labels are becoming irrelevant. They’ve become terrific at marketing while totally looking past the content. In fact, today, most successes out there are due to great marketing rather than great – or even good – music…and there’s a public out there that’s tired of it. It cuts across all demos as listeners change their listening patterns to include more classics and fewer currents. A quick scan of most of today’s releases demonstrates the lack of writing and performing talent making their respective ways to the listener. So while the labels are busy marketing, they’re also busy screaming, “Pirate! Pirate!” instead of finding real talent. Younger demos are more sophisticated – or less easily fooled. Either way, most won’t pay for a CD with one good cut. And in the last few years, there haven’t even been many of those! Sure, go ahead and cite a couple of albums or tracks but, by and large, the music creative world is a mess. That mess “sticks” radio with short playlists and uninspiring music and the medium suffers greatly. Not even the synergies that the CBS’s and Warners of the world can bring will turn it around. You can use tracks from company labels in TV shows (subliminally or with the blatant display that CBS includes in shows like Numbers); you can offer teases or select free tracks, or parade artists in a never-ending column onto the sets of TV talk shows; you can license tracks for commercial use, hoping they’ll stoke sales. Fact is, if the content isn’t there, well, there’s not a lot of hope. At the same time, radio broadcasters, seeing revenue fall came up with the ideal solution: crank up the commercial load. That’s worked really well! Some, Clearchannel, the nation’s largest radio group owner, included, have returned to less nonprogram time. It hasn’t helped much though since the chase for listeners has shortened every station’s playlist. Instead of getting tired of commercials, listeners just become fatigued from listening to the same music over and over and over and… The combination of label and broadcaster errors is a recipe for disaster. As this problem spirals upward, another wrench was tossed into the works: the performers have stepped in, looking for more money, themselves. Again, what was a symbiotic relationship for the same 70 years is now becoming adversarial as the US House considers HR4789,1 the “Performance Rights Act.” The bill, now voted out of committee with a recommendation for passage by the full House, seeks pay for play – with performers on the receiving end. These payments would be above and beyond the ASCAP, BMI and SESAC payments. It disregards the fact that radio is the main outlet for release of new material and new artists. It forgets that radio is a nearly piracy-free medium where airplay is of full cuts rather than samples. The "Local Radio Freedom Act" recently introduced offers to defuse the issue but it won't keep a vote on the Performance Rights Act from coming to a vote. There are numerous arguments for the Performance Rights Act, “Other countries do it.” “We do all the work.” “We’re getting killed by online piracy” are among the top reasons. Nevermind that many of the other countries are, let’s say, less than capitalistic, that the broadcaster is still the main outlet for sampling of new music, and that it isn’t the broadcast music but digital originals that are copied and offered for download. The broadcasters have countered, arguing their position as a major force in music sales and ignoring the longer-term use of music on the air which may contribute little to additional disc sales. The disagreement – and the proposed bill – come at an interesting time. It’s not music tastes that make it so. It’s the technology. Forget peer-to-peer or other file sharing, neither are part of the scenario. The technology is “tagging” and Clearchannel is its biggest proponent…and it may well set the entire licensing structure on its ear. This technique is more than a new wind in technology. It may well become a tornado. Simplified, tagging allows radio listeners to mark or “tag” a particular song as they listen then receive it directly to an iPod – for a fee. Imagine – direct accountability and traceability. Broadcasters, performers and the public will know immediately and exactly what music works and what doesn’t. Wellllll. The proof of the pudding will be in the tasting. And the tasting will be measured in converted tags. Think about what the concept will expose: - How good’s the content? Simple enough. The more they like the cut, the more likely they are to pay to download it. It’s a pretty even playing field. Not flat but not bad - Who’re the hot (and cold) performers - Between the performers and the broadcasters, which is the dog and which is the tail That is what will be the taste of the pudding…and for some performers it may be bitter. After all, track and performer popularity will become very clear through directly traceable sales. If you don’t measure up in sales you don’t get any more play! Now imagine the impact. Imagine how long Clearchannel – and others adopting tagging – will keep playing performers whose music doesn’t generate tagging revenue. Imagine the shortened playlists, further reduction in formats, and boring repetitiveness that could occur. Then again, think about the control that Clearchannel could seize, playing what they see fit and, therefore, guaranteeing tags and sales only for those selections. That feeds right back to the labels – those guys ostensibly responsible for finding, developing and promoting talent. With tagging, who needs the label? In fact, you can look to Clearchannel to be a label. So if it all plays out, where’s the recovery to come from? It’s not in more-of-same. It’s not in bigger promotions. It’s in getting more decent music and getting it to market. That means radio, online, films, every outlet possible. Listeners are ready and willing to pay for music they really like. They’re not as willing to pay for poor quality. If the performers can produce quality content, the relationship with broadcasters works. If not, the tug o’ war will continue. This clearly will be a test of radio’s power. If Clearchannel succeeds, you can look for a gigantic swing in control. Labels will come crawling, hoping to talk Clearchannel out of creating its own label. Performers will rethink their demands for payment as stations begin to base their play on tagging sales, reducing or eliminating play from poor performers (pun intended). In fact, the money may start flowing in the other direction. Remember, it’s not payola if you tell people you’re getting paid! (317, Communications Act of 1934). BMI and ASCAP: take note. The final outcome? Will tagging underscore the need for good content? Can tagging shift the balance of music power to radio? Well, if radio had the slightest idea of what it’s doing, it would get on the stick with HD and with the implementation of tagging. Unfortunately, it doesn’t. Clearchannel will give tagging a great run but everyone answers to the “Q” these days so if it doesn’t work in 89 days, performers may well be safe. OK, that’s hyperbole, to be sure, but probably not too far off. In the meantime, we can look forward to plenty of tracks being forced under TV action, bad matches between commercial beds and their video content, and the continuing parade of unsavory music and performers hawking their wares on talk shows. Here’s the originally introduced bill: Performance Rights Act (Introduced in House) HR 4789 IH 110th CONGRESS 1st Session H. R. 4789 To provide parity in radio performance rights under title 17, United States Code, and for other purposes. IN THE HOUSE OF REPRESENTATIVES December 18, 2007 Mr. BERMAN (for himself, Mr. ISSA, Mr. CONYERS, Mr. SHADEGG, Ms. HARMAN, and Mrs. BLACKBURN) introduced the following bill; which was referred to the Committee on the Judiciary A BILL To provide parity in radio performance rights under title 17, United States Code, and for other purposes. Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, SECTION 1. SHORT TITLE. This Act may be cited as the `Performance Rights Act'. SEC. 2. EQUITABLE TREATMENT FOR TERRESTRIAL BROADCASTS. (a) Performance Right Applicable to Radio Transmissions Generally- Section 106(6) of title 17, United States Code, is amended to read as follows: `(6) in the case of sound recordings, to perform the copyrighted work publicly by means of an audio transmission.'. (b) Inclusion of Terrestrial Broadcasts in Existing Performance Right- Section 114(d)(1) of title 17, United States Code, is amended-- (1) in the matter preceding subparagraph (A), by striking `a digital' and inserting `an'; and (2) by striking subparagraph (A). (c) Inclusion of Terrestrial Broadcasts in Existing Statutory License System- Section 114(j)(6) of title 17, United States Code, is amended by striking `digital'. SEC. 3. SPECIAL TREATMENT FOR SMALL, NONCOMMERCIAL, EDUCATIONAL, AND RELIGIOUS STATIONS AND CERTAIN USES. (a) Small, Noncommercial, Educational, and Religious Radio Stations- (1) IN GENERAL- Section 114(f)(2) of title 17, United States Code, is amended by adding at the end the following: `(D) Notwithstanding the provisions of subparagraphs (A) through (C), each individual terrestrial broadcast station that has gross revenues in any calendar year of less than $1,250,000 may elect to pay for its over-the-air nonsubscription broadcast transmissions a royalty fee of $5,000 per year, in lieu of the amount such station would otherwise be required to pay under this paragraph. Such royalty fee shall not be taken into account in determining royalty rates in a proceeding under chapter 8, or in any other administrative, judicial, or other Federal Government proceeding. `(E) Notwithstanding the provisions of subparagraphs (A) through (C), each individual terrestrial broadcast station that is a public broadcasting entity as defined in section 118(f) may elect to pay for its over-the-air nonsubscription broadcast transmissions a royalty fee of $1,000 per year, in lieu of the amount such station would otherwise be required to pay under this paragraph. Such royalty fee shall not be taken into account in determining royalty rates in a proceeding under chapter 8, or in any other administrative, judicial, or other Federal Government proceeding.'. (2) PAYMENT DATE- A payment under subparagraph (D) or (E) of section 114(f)(2) of title 17, United States Code, as added by paragraph (1), shall not be due until the due date of the first royalty payments for nonsubscription broadcast transmissions that are determined, after the date of the enactment of this Act, under such section 114(f)(2) by reason of the amendment made by section 2(b)(2) of this Act. (b) Transmission of Religious Services; Incidental Uses of Music- Section 114(d)(1) of title 17, United States Code, as amended by section 2(b), is further amended by inserting the following before subparagraph (B): `(A) an eligible nonsubscription transmission of-- `(i) services at a place of worship or other religious assembly; and `(ii) an incidental use of a musical sound recording;'. SEC. 4. AVAILABILITY OF PER PROGRAM LICENSE. Section 114(f)(2)(B) of title 17, United States Code, is amended by inserting after the second sentence the following new sentence: `Such rates and terms shall include a per program license option for terrestrial broadcast stations that make limited feature uses of sound recordings.' SEC. 5. NO HARMFUL EFFECTS ON SONGWRITERS. (a) Preservation of Royalties on Underlying Works- Section 114(i) of title 17, United States Code, is amended in the second sentence by striking `It is the intent of Congress that royalties' and inserting `Royalties'. (b) Public Performance Rights and Royalties- Nothing in this Act shall adversely affect in any respect the public performance rights of or royalties payable to songwriters or copyright owners of musical works.

Thursday, July 9, 2009

Safety and the Old Guys

Just read an article about tech management dusting off the old skills - getting back into the troubleshooting business. Used to be (ah, the good old days) everything was troubleshot to the component level. Little hard to do now..."I'll change the 9th fet on that array of 12 switches"...but, nonetheless, there're a lot of problems that can be fixed on the bench instead of sending the box back to the manufacturer or ordering a whole new card. And the time is definitely right for anyone with those skills to assert them. A half hour working through that ARC-16 can save a $900 round trip for the unit. Couple that with the pressure to cut costs, and it makes bench servicing that much more attractive. For anyone who's been content sitting at a desk, or even in the field but managing others, hauling out the VOM and scope brings with it safety concerns - ones we all observed as second nature in those component days. Here're some thoughts on safety. Disclaimer: I'm not a lawyer. I don't play one on TV. However, safety around electronic gear can get pretty complicated. I don't pretend to have all the bases covered here. Use logic! That said, these are some points we all need to remember. Yeah, some of the comments are tongue-in-cheek but it's only to make the rest of it stick. Dress the Part: What? Not the greenie...just remember to take off the watch, rings and all the gold chains. But it's low voltage only. Try this: make a "wedding ring" out of a piece of number 12 copper and lay it across a good sized 12 volt battery. As it's glowing, imagine your finger inside. Gloves...good enough for the Lone Ranger, good enough for me...especially the hand holding a probe. Shoes...something in a brown slip-on? Try a pair that provides some electrical insulation. I've heard that you can increase your body resistance by wearing a striped shirt - grey-white-green. Light up your Life: Play a little Debby Boone - or put some light on what you're doing. I know I've moved from working in the shadows to needing at least one light on the work, and a bright one, too! "I want every available light dumped out on that runway" - Lloyd Bridges, Airplane You Gotta Have Friends: Working alone isn't a good idea - even the low voltage jobs. Dead Circuits: If at all possible, only work on dead circuits. Takes a little longer to turn the power off, connect a clip lead, power up, read the meter and power back down, but it's a lot safer than probing a hot board. A) less of a chance of getting fried and B) no accidentally shorted traces that cause a transistor to blow in order to protect the fuse. When Ground isn't a Good Thing: When you're the low-Z load. Working on a cement floor or a damp one, or a metal workbench where you can make contact with it - all invite a little extra current that, frankly, no heart needs. When Ground shows up Uninvited: Most test gear is unbalanced (probably since most engineers are, too). That ground lead you're clipping somewhere could, under some circumstances, make the chassis of the test gear hot. Test this by grabbing a hot dog with a fuse puller and holding it between the chassis of the test gear and ground. If it starts to smell like you're grilling out, double check the gear. The One Hand Rule: Keep one hand in your pocket and only use one hand if you have to probe a live board or circuit. Short it Again: Check that filter cap (or other storage devices) - then short it - a second time - (leave it shorted if you can or at least check with a meter) before prowling around in a circuit. Don't Reach: If you can't see it, you can't really test it - and you don't know what charge that whatever-it-is is carrying. and Don't Point: OK. Seems silly, "Don't point." But you can draw an arc from an energized circuit. Once, again, even if you're 50+j0 ohms, you don't want to be the load. It's happened. and, if you're Tired: Don't be a hero. Pack it in. Nothing better than bopping in at 10 after working till 4 to get a piece of gear working and seeing all the smiles on the folks actually using it. But it's a heckuva lot easier to make mistakes at 4 than at 1. When that 5 mic capacitor you put in fails because you couldn't see that the original was 50 volts and not 35, your fans suddenly act like they're at a Phillies game and down 7 runs. Len Watson Scope+Focus, Inc.