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From Harlen Smith's Board Embedded Chips/Manufacturing

I am not a technician but the explanation speaks for itself. Trouble.

FWD: Q7 transistors not compliant

From: Date: 22 Jan 1999 Time: 22:02:32 Remote Name:


Date: Tue, 19 Jan 1999 13:49:00 -0500 From: polcat X-Mailer: Mozilla 4.05 [en] (Win95; U) To:,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

Q7 Transistors found to be not compliant with Y2K!

The Y2K board of the Society of Electronic Design Consultants announced today the results of an exhaustive study of Y2K component compliance issues. In addition to confirming the well documented existence of non-compliant 555 and 556 timer circuits, the board also announced that Q7 transistors, often used in older voltage controlled oscillating LC timing circuits, and still widely used in a variety of repetitive pulse and amplification circuits, are in fact not compliant with Y2K requirements.

Because of the extensive use of Q7 transistors in electronic devices (it is estimated that some 92% of electronic devices currently in service contain at lease one of these transistors) the board urged all electronic technicians to check circuit diagrams for these transistors and replace them with Y2K compliant components any time they are working on any electronic system. The board also notified the usual governmental, military, communications, transportation, financial, manufacturing and technology communities of the urgency of this situation.

The problem with Q7 transistors stems from the their inability to discern the difference between the last millisecond of the present millennium, and the first millisecond of the next millennium. This causes the transistor to go into self oscillation in AC circuits, and stay low in DC circuits. In the AC circuit, the oscillating rate is dependent on the differential between voltages of the PNP values.

Although a seemingly infinite number of individual part numbers and designs were used as Q7 transistors throughout the years, all Q7 transistors share a basic commonality in that they are always NPN or PNP types. The original part number of each Q7 transistor must be identified and if a Y2K compliant part is not available as a direct replacement, a compliant substitution part whose specific operating characteristics are closely aligned with the original specification might be used with minor re-tuning of the circuit.

Some potential problems associated with non-compliant Q7 transistors at the beginning of the next millennium are: 7 A continuously busy signal whenever a phone is used, caused by self oscillating of the Q7 transistors in the audio circuit. 7 Unstable ignition timing in electronic ignition controlled vehicles, which could result in a no start condition. 7 Uncontrollable oscillations in AC stereo speakers. 7 Interruption in satellite and communications systems. 7 Potential loss of military defense capability is classified. 7 Most personal computers will not function.

I'm glad I went shopping today.

-- Mike Lang (, February 21, 1999


I know enough about transistors to strongly suspect that this "Q7 Transistors found to be not compliant with Y2K!" announcement is bogus. Several of the statements within it seem nonsensical or ridiculous.

-- No Spam Please (, February 21, 1999.

This is bullshit.

A transistor is two back-to-back diodes. As STUPID a device as you can get!!! A transistor does not give a flying-fuc? about any discrete measure of time, such as milliseconds.

A 555/556 timer-chip wouldn't know a date from a horses rear.

Somebody somewhere is really clueless!!

Understand, I expect "Really Big" Y2K problems, but c'mon....

-- Anonymous99 (, February 21, 1999.


-- No Spam Please (, February 21, 1999.

>>The problem with Q7 transistors stems from the their inability to discern the difference between the last millisecond of the present millennium, and the first millisecond of the next millennium.<<

This is a problem?

Someone is playing a little joke.

-- Elbow Grease (, February 21, 1999.

OK Who actually read farther than the general description of a transistor, "PNP or NPN" and continued to believe this?? c'mon folks!! This should have lodged in EVERYBODY's critical reality filter!!!

I LOVED IT!!! ;+)

Chuck da Night Driver

-- Chuck, night driver (, February 21, 1999.

Chuck, night driver;

>OK Who actually read farther than the general description of a transistor, "PNP or NPN" and continued to believe this?? c'mon folks!! This should have lodged in EVERYBODY's critical reality filter!!! I LOVED IT!!! ;+)

Chuck da Night Driver<

By then I was laughing too hard. He lost me with Q7, and the "usual" notifications. I put in with the AC batteries.

It was funny though, and I needed a laugh.


-- sweetolebob (, February 21, 1999.

LOL--funny stuff. Did you read the follow up on noncompliant solder?

-- PNG (, February 21, 1999.

We will undoubtedly see many more such 'articles' in the coming months. To those who have worked in or around the industry, the hoax is clear. But to the many people not directly involved, it is very hard to decipher.

All the more reason to not to overreact to any one article you read - it may be a total fabrication (as in the case of this one or as in the case of many corporate 10-Q statements). If you find something that looks troubling, do what Mike did and post it here to let the rest of us see it. Chances are, there is someone here who can clearly identify a hoax. Wait until you get a number of responses before judging the value of the information.

There are a number of participants here with good technical backgrounds and though they may not always know all the answers, they do have pretty good BS meters. Something which is clearly a hoax will be found out fairly quickly.

It is most unfortunate that deliberate disinformation seems to be the tool of choice for so many groups today. It is possible that the above piece was intended only as an 'inside joke' -- to be distributed among engineers who would instantly recognize its sillyness. Perhaps someone then forwarded it to a public forum. I don't know -- but you can bet we will see more of this, some diliberate and some unintentional - from many different groups with different agendas.

Disinformation, whether deliberate or unintentional, can best be countered with public exposure and debate. If you are new to following the Y2K issues, be aware that you need to get your information from as many different sources as possible.

"We've arranged a global civilization in which the most crucial elements...profoundly depend on science and technology. We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster."

-Carl Sagan, 1996

-- Arnie Rimmer (, February 21, 1999.

Thanks all. As I said, I don't have a clue technically. What is so obvious to you is not to me. Glad you could set me straight and Arnie is right about this being a good place to filter info. Anyway, I am glad to be able to supply a smile to all of you that have helped me so much.

-- Mike Lang (, February 21, 1999.

Yes, and Hydrogen monoxide may kill us all. The humor is not lost on me, but I don't visit this site for yuks. I have been looking for a year for information on specific controllers that are not compliant. It would really be useful to know of any actual devices that will fail, so that repairs can be made. Help, anyone?


-- Robert Neely (, February 21, 1999.

Q7 transistors? Get a pencil and renumber the parts on the schematic hahahahahaha... ooops then the Q6 transistors will cause problems!

To the uninitiated this DOES look legitimate. Also notice that nobody here has pointed out the facts why it's NOT legitimate. We could have serious flame ware over this otherwise humorous post that was first circulated MONTHS ago.

For instance, the LM555 chip is an ANALOG chip, right? No, it's a digital/analog hybrid! If it's digital it might have y2k problems right? Might, but I can tell you it doesn't because it's way too simple a device. And if you research it you will find that the 555 has a "clock" circuit in it, or can be configured as a "digital clock signal". In point of fact this chip has a total of 2 bits of memory, so it should be obvious it cant keep track of the date, but unless you know what you're seeing you might convince yourself otherwise.

Did you hear that y2k compliant solder can cost as much as $500/ounce? Anybody want some, I've got a good deal for only half that price.

BTW anyone looking for noncompliant RTC's, motorola has a list of theirs on their website.

-- PapaSmurfYune (, February 22, 1999.

Robert: Why would you be looking for PLC's that fail? Where did you hear that PLC's fail? That's like looking for leprichans. Siemens has one that rolls from 99 to 01 instead of 00, but I don't anyone in the industrial controls business still looking for possible PLC hardware failures. It's the system and software. No wonder your frustrated, my friend. If your not an industrial customer, you won't get access to technical sites and data from manufacturers...

-- PNG (, February 22, 1999.

Also notice the tone of all the replies. Assume you really had some suspicions that the original post "might" be legitimate, what sort of reaction would you have? No wonder nobody can figure this thing out. No wonder there are so many flames...

-- humback (, February 22, 1999.

And of course all the R7 resistors are y2k non-compliant too, and they have to be matched for wattage, tolerance, and type.

PS it's a bogus piece.

-- Blathering Idjit (, February 22, 1999.

harlan's reply:

Re: FWD: Q7 transistors not compliant

From: Harlan Smith Date: 22 Feb 1999 Time: 06:51:03 Remote Name:


For the record, I don't see the messages posted to this Forum.

The message is not a hoax but rather just a SILLY JOKE and does not deserve intelligent comment.

Almost every statement is in disagreement with facts. For example, Q7 transistor refers to no specific device but rather is just the 7th transistor on the schematic diagram and parts list.

Transistors and timer circuits of the types mentioned intrinsically cannot have Y2K problems as they have no means for processing date information.


-- Lewis (, February 22, 1999.


-- vbProg (, February 22, 1999.

And if the power goes out in the second microsecond after the transisition ..... is the resistor it still compliant?

Can I bend Y2K compliant solder, or does it work harden and turn brittle? If a solder a compliant resistor, can I still get the lead out, or must I use a black LED to trace the circuit? What if it's a metric circuit, do the electrons turn the other direction, or is that only in AC/DC conversion?

Questions, do you convert metric electrons anyway.

-- Robert A. Cook, P.E. (Kennesaw, GA) (, February 22, 1999.

Guess somebody should tell 'gump' Martin he needs to verify his facts before he posts... that's the 4th time in as many weeks!

-- Mutha Nachu (, February 22, 1999.

Whose he? Didn't post least not under that name.

-- Robert A. Cook, P.E. (Kennesaw, GA) (, February 23, 1999.

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