Amclaussen

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Amclaussen

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  • 10.20.2011
  • Simple reverse-polarity-protection circuit has no voltage drop
  • I keep seeing relay coils being "clamped" with a simple diode to "remove" the spike... It appears that the simple diode is NOT the best protection. When looking at installing some relays into the cooling fan circuit in one of my cars, that happens to have a computer controlling the fuel injection and ignition, which is a delicate device hard to find and replace, I ran across a pair of notes written by TYCO, which explains in detail the pros and cons of the simple diode. One is titled: "The application of relay coil suppression with DC relays" document 13C3311 Printed U.S.A. IH/11-98. The other is titled "Coil Suppression Can Reduce Relay Life", document 13C3264 Printed U.S.A. IH/12-00. Both show the pitfalls and disadvantages of using a simple diode when using relays. It apperars that using a simple diode or single resistor is not the best way, and they suggest to use a combination of a diode with a Zener, to provide a better system.
  • 03.18.2014
  • Neil Young: Say Yes to 24-bit/192-kHz audio
  • Absolutely true: I keep an old, first generation CD player made in 1983 by Hitachi, just to compare with later generations; The difference is quite noticeable, even for untrained listeners. BUT when the CD was launched, 99% of people claimed it was THE PERFECT audio format. Indeed, it was free from "Scratch", Wow and Flutter, Rumble, Hiss, and was much more compact, convenient and 'nice'. The truth, it sounded harsh. (I guess I keep that old player because it helps me to convince people that says "CD is OK for me"). Lack of appreciation is why we have mediocre standards in many fields, plus the "OK for me" attitude. As a reference, that old Hitachi 1983-vintage CD player was audibly compared to a 1998 Harman Kardon CDR-30 that is in a comparable class and price bracket. Both were listened to through a very good quality headphone amplifier (Lehmanaudio Black Linear Cube) and Shure SRH-940 headphones while feeding the signal of two identical CDs played synchronized feeding the output of the old hitachi to one channel and the HK to the other, and the test was repeated interchanging both players/channels.
  • 03.26.2008
  • MP3: Audio boon or bane?
  • The true threat to better audio is the lack of appreciation in consumers and a too complacient attitude ("It is OK for me"...) . For many decades, the better audio, video, cinema and photography "standards" adopted in North America were left apart, and mediocre ones were selected. That is why Americans had NTSC (Never The Same Color), when Japan had tremendously better High Def analog TV (even Europe had more lines per field and a better color systems than Americans: the hue control knob which is present on virtually all NTSC TV receivers is absent on SECAM and PAL TV receivers). Or why European cars had have way much better headlights than American cars, or why Canadians had to invent IMAX, or why VHS won over Betamax, etc. The best approach to a better sound reproduction at home (or portable) will have to set the aims not higher than achievable, nor lower than desirable. It seems to me that objectives towards lower standards is not justifiable . One thing is to avoid over-hyped goals, and another to suffer a compromised, mediocre format like we have suffered for many years, just because someone said “it is OK for me”.
  • 03.18.2014
  • Neil Young: Say Yes to 24-bit/192-kHz audio
  • You are right Katgod, the kind of music matters. Most younger persons have not learned to listen carefully-(it is difficult to listen when a heavy metal band is using heavily-distorted electrically amplified instruments to play at 120 puls or minus 5 dB all the time). Music of yesteryears, acoustic, played with a real dynamic range inside a proper place, is the only way to discern nuances like, for example an Steinway from a Bosendorfer, from a Yamaha, from a Baldwin. But it can be done. It only takes some training, a lot of dedication and taste from the listener, and an honest sound equipment, not necessarily the most expensive or esoteric, just good enough, and mainly: a GOOD recording. But, if a too low quality format restricts the auditory illusion, those nuances will be sorely missed, lost forever.
  • 03.18.2014
  • Neil Young: Say Yes to 24-bit/192-kHz audio
  • A higher resolution format is not only the one capable of higher frequency reach. Music is composed of a very complex signal, barely reproduced by today's systems. your impresion that HF Ultrasonic components are the only differences is perhaps a little simplistic. There is a lot more than just frequency response...
  • 07.01.2017
  • The Walkman is introduced, July 1, 1979
  • While the Walkman indeed had its attractives, some time later AIWA launched a unit that was much better. Even when the sound of the Walkman was shockingly revolutionary, it had a lot of circuit hiss, which added to the already high hiss from the casssette tapes was its limiting factor. Tha AIWA also had a switching PS, but used three AA cells and worked best when using rechargeables. The original Walkmans lacked a FM receiver, so Sony produced one that installed inside the cassette bay, thus prohibiting recording from FW stations. AIWA, on the contrary, built a very nice quality FM receiver into the chassis, thus the user could record from FM. The mechanical quality of the AIWA units was quite better than the Sony, using metal instead of plastic in many places. My unit still works properly, which is amazing considering that it is today 36 years old! BUT, the only gripe with it, was that the Sony over the ear headphones were so much better than the AIWA ones, that I had to buy an extra Sony MDR-3 set to be able to fully enjoy my AIWA recorder!
  • 07.01.2017
  • The Walkman is introduced, July 1, 1979
  • Well, in regards to sound leakage, the "ear-bud" is not the best. The better ones are the In-Ear or canal-earphones, like those made by Shure, Sennheiser, and others; that are inserted into the ear canal and therefore can provide better isolation and much better sound (and cost accordingly!). For the very best results, the more professional in-canal earphones can be complemented with a custom moulded ear tips, that offer the highest isolation and comfort. At that level of quality, you can find multi-driver technology complete with crossovers. A good digital player together with a set of those can rival any conventional audio system at a minuscule fraction of the price. Hard to believe that all of this started with the Walkman!
  • 07.01.2017
  • The Walkman is introduced, July 1, 1979
  • While revolutionary, I quickly found that the lack of Recording capability was a serious limitation. Most people are what I consider "passive" listeners, happy with just reproducing the commercial music. But I also liked to listen to LIVE music, recording live performances made me aware that even with "low" quality portables, live performances had a certain quality that put them miles above the over-produced, over-massaged, multi-dubbed commercialrecordings. My FIRST generation humble cassette recordings were critically acclaimed by artists or their musicians/technicians when hearing their own sound, because most of them did not have portable recorders and seldom knew exactly how they sounded. So in 1981, I sold my Walkman player and bought a much better sounding AIWA unit, capable or recording in Stereo. Its erase head was a permanent magnet, that actually ADDED more noise than the noise floor of a new tape, so I removed it and used new tapes every time. An inexpensive pair of Tie-clip mikes got more stereo separation when I recorded from first row center. Months later Sony came out with the first Walkman-Pro that allowed the use of the best Metal Tape (TDK) and Dolby-B (which NEVER worked properly, always removing Treble too much. But those tapes, when listened through better headphones sounded exceptionally clear for being FIRST generation. Later on I got a Harman-Kardon PMD-430 cassette recorder with DBX system offering a big dynamic range, but also introducing some artifacts. (Curiously, most musicians preferred the sound of the Sony Walkman-Pro over the HK) Later, I used a Sharp MS-702 minidisc that sounded superbly, and finally a completely solid state (SD card) EDIROL by Roland 24 bit-96Khz recorder, that still does not convince me completely. Today, more than the electronics, it is the tremendous development of the In-Ear or "canal earphones" that is capable of having a truly outstanding sound reproduction hardly imagined when the Walkman appeared.
  • 07.11.2017
  • Last slide rule manufactured, July 11, 1976
  • I seriously question present day HP for their present day philosophy: 1) Quality: In the 60s-70s HP was a good company devoted for delivering best quality. It has been written that Mr. Packard himself had a meeting when they found a bug in the HP-35 delivering slightly wrong results in a given function. Someone said: "What if we just say nothing? Mr Packard became so infuriated that he broke in two a pencil he had been holding, and loudly told that "I PREFER NOT TO MAKE A SINGLE CENT THAN CHEATING ON MY CUSTOMERS... we will inform every owner and offer them a replacement calculator at no cost". Evidently, after thieves like Carly Fiorina and her "Golden Parachute", former HP quest for being fair to its customers evaporated. 2) Reliability: My old HP-45 still works perfectly, only replaced rechargeable cells in its pack. Charger failed at 30 years of use, calculator still like new, just a little paint from some lettering partially gone, but guess I can't complaint for I use my HP-45 DAILY since 1973. New Office-Jet printer already threw out several damaged or misprinted pages. 3) Sustainability: Fabricating a printer that weighs 24.2 pounds to be trashed so soon is not ethical from a sustainability viewpoint. 4) Company's Ethics. A company that not only cheats on the customer, but installs chips in every cartridge that inform the damn company about its use and promptly displays messages pressing the owner to replace cartridges that are partially full does not deserve my money. I'll go w/ EPSON, who makes OWNER REFILLABLE printers, independently of price. One thing's for shure: I'll not buy HP again!
  • 07.11.2017
  • Last slide rule manufactured, July 11, 1976
  • Michael: I wasn't “printing a book” on the "set-up" cartridges, the damn HP printer gave less than 60 prints on top quality HP paper that shouldn’t absorb too much ink; pages hadn't solid colors, most were graphs with THIN colored lines, nothing that demanded too much ink. I guesstimate half of them being just black text. So, it wasn’t me in a "weird something-for-nothing mindset". Then, this P.O.S. didn't allow me to continue to print in black only, even when the black cart shows more than 3/4 and manual says you can continue with an empty cartridge; not true. It just keeps asking for new cartridges, 1st the Cyan, so I ran and bought an ORIGINAL HP Cyan cart, replaced it and the printer displayed a second message demanding the Yellow one, so I was stupid enough to buy a second cartridge, but as soon as I installed it, the printer announced it now needs the Magenta one. The two carts have now cost me MORE than a new printer. I've been TOO indulgent with the "new" HP, and having tried unsuccessfully to un-block the damn printer with their (absolutely useless) "service", will continue to exhibit them.