Share your thoughts:Why are some brands more popular on specific instruments? - Page 1
Forum section: electronics / general

author: bsgd
author_rank: Regular Contributor
timestamp: January 24, 2012, 11:01:49 pm
content: Okay, so this is an open discussion about why some brands are much more popular on some specific instruments, considering all the instrument 'evolution' during the past 40 or 50 years.For instance, lets talk about multimeters. Fluke handheld multimeters have always been more desirable than HP/Agilent ones. On the other hand, I have noticed that HP/Agilent benchtop meters are more desirable and also reach higher prices on the used market.Why is that? Is it just a matter of quality? Is it just because some companies have a much longer story on developing a specific type of instrument and so they share much more time proven robustness/accuracy/quality?I have this 'thing' for old gear, and I have been looking for this stuff on ebay for some time now, and I noticed you can get some instruments from some well known brands for almost nothing while other kinds of instrumets might cost a small fortune.What brands do you prefer for each instrument type?

author: amspire
author_rank: Super Contributor
timestamp: January 24, 2012, 11:45:50 pm
content: There are several reasons for the popularity of instruments from companies like HP/Agilent, Fluke and Tektronix.A huge issue is availability of user and service manuals.There are many companies that have a policy of supplying service manuals only to Authorised Repair centers. This means that modern microprocessor controlled instruments can be near impossible for a hobbyist to repair, however good the instrument is.Companies like Fluke and HP have a long time reputation of leadership and quality, of rigorously meeting advertized specifications, of longevity, of spare parts availability.I think some companies are very protective and insular as if they are scared their good ideas will become know. HP was always extremely proud and open about its good ideas, and they published them in the HP Journal. This means that with many HP instruments, you can not only get the service manual, but you can get a well written explanation of some of the refinements in the way the instruments is designed. So when there is a custom IC, you are often able to find detailed description of that custom IC.All these companies have very informative service manuals often including a section explaining how the instrument works, which is far better then companies who provide minimal service information.Many companies seem to want instruments over 10 years old to just go away. It is amazing how many companies who made extremely fine instruments will have websites that are completely purged of the slightest mention of the old instruments. To me this is a total lack of pride and respect for the history of their company - if they don't respect themselves, why should anyone else. They may have a great instrument today, but next year they will have a new model, and they will want to forget about this years instrument as much as possible.Richard

author: EEVblog
author_rank: Unknown
timestamp: January 24, 2012, 11:55:29 pm
content: Quote from: bsgd on January 24, 2012, 11:01:49 pmIn the case of Fluke, it's a combination of a lot of things.They pioneered the handheld DMM, and it of course helped that they were designed and build well, and had a novel feature like TouchHold. But they also had extensive industry marketing back in the 80's, cleverly seeding the brand as THE meter to have with various full page ads blasted at you for years on end. And bingo, 20-30 years later they still have the same rep that will take some beating.Dave.

author: Unknown
author_rank: Unknown
timestamp: January 25, 2012, 12:05:34 am
content: If you look at current products, a lot has to do with being an established brand. For example, Fluke has made good quality handheld DMMs for a long time, while Agilent only (re)entered the market a few years ago. Agilent has been making bench DMMs almost since they were invented. Fluke only introduced a competitor for the industry standard 34401A (introduced around 1990) about five years ago (8845A/8846A), they had no 'affordable' 6.5 digit DMM before that. For a number of years, their only bench DMM was either the 5 digit Fluke 45 or an exotic rebranded Agilent DMM.Not sure why older Fluke bench DMMs would be worth less, the Fluke 8840A usually seems to be more expensive than its contemporary HP 3478A. Not sure about the Fluke 8000 series, they don't sell for much, but they're usually fairly low spec. Not sure how their prices compare to similar HP DMMs like the 3466A and 3465A.Tek has long be the scope brand to buy. HP scopes often had inferior triggering and bad usability on the front panel controls. They had by far the most advanced CRT technology. Now their advantage has disappeared since CRTs are obsolete, and they're just one of the big three.For used equipment, availability of parts and documentation probably plays a major role. You can either buy a piece of Schlumberger equipment and spend a lot of time tracking down a manual, or buy HP and download the manual straight from Agilent's website.

author: bsgd
author_rank: Regular Contributor
timestamp: January 25, 2012, 12:11:26 am
content: Quote from: amspire on January 24, 2012, 11:45:50 pmThis is very true and something I didnt really think about. But makes a LOT of sense. Coming to think of it, yes, I do buy instruments from companies that have a long support history and which I know I will be able to get repaired in the long run.Quote from: EEVblog on January 24, 2012, 11:55:29 pmFirst, Dave, thank you for creating the blog, forum and website. You are the person that encouraged me to start building my own lab! Thanks!Yes, I guess industry does play a major role in this game. If something is considered an industry standard, it must be very good to survive such harsh environmet. I work in a pretty big industry and I know these instruments must be very well built to survive.Interesting fact: I have an Agilent HP 6632B power supply. The very same day I got it (brand new!) I managed to drop it 5 meters until it hit a hard ganite floor. Aside from a few scratches and dents, it survived nicely!

author: bsgd
author_rank: Regular Contributor
timestamp: January 25, 2012, 12:21:16 am
content: Quote from: alm on January 25, 2012, 12:05:34 amI do have a Fluke 8810A bench meter and I quite like it. Sure, I prefer Agilent ones because they feel more reliable when in use, but the Flukes are certainly good meters. And they are usually cheaper, most probably because of their not-so-long research and development on this kind of instrument as you suggested.As for scopes, I dont own any Agilent or HP but I do know Teks have been the king in this area. Today, I'm not sure which brand has the best scopes, but I do know at work all we have are Teks and they handle the job quite well. I dont really like the user interface on them, but they are wonderful instruments.

author: saturation
author_rank: Super Contributor
timestamp: January 25, 2012, 01:43:59 am
content: I think in the end its the quality of product, its association with the brand name, very much like other products. However, unlike consumer items, T&M gear have useful lives measured in decades, so a product with such a reputation is very difficult to overcome.The 87V Fluke DMM has been around since the late 1980s, the Agilent 34401a from the early 1990s, 3458a from 1989 [ enduring while most of the 8.5 digit Metrology DMMs have folded]. I think oscilloscopes are not in the same position because analog, where Tek was the unchallenged leader, has all but gone and the models have a shorter half life.Likewise, among the second echelon brands, Global Specialties has an established reputation in low cost pulse generators: the 4001 and the 4010 are still being made, the casing and color schema are different, but the design is over 20 years old.Sanwa in Japan still makes the YX360, an analog VOM, which was designed in the late 1970s. I rarely 'see anyone in the west use it, but it has a popular following in Asia and is part of Sanwa's mystique and reputation in DMM.Simpson, once the king of VOM, still makes its signature 206 to this day, this wastheanalog VOM for accuracy and durability, designed in the 1930s! I'm not sure which industry still uses it.Finally, the modern versions of these models have incremental improvements, but they are more similar to their originals than different.

author: JoeyP
author_rank: Frequent Contributor
timestamp: January 26, 2012, 11:28:18 pm
content: I can't speak to a comparison of all brands, but I can tell a story of why (in my opinion) HP instruments became so popular. I used to work on test equipment back in the 1980's-1990's. Up until the late 1980's, HP had an amazing support policy. Not only did they offer very complete service manuals, but they bent over backward to help support techs. As one example, back in that day if you got stuck on a troubleshooting problem, you could literally call HP and be put through to speak directly with one of their bench techs! Yes, their repair techs would, if needed, actually walk you through troubleshooting the problem over the phone - at NO charge. Another example, was that if you were in a hurry for parts, you need only mention this to their parts department and they would expedite the order at no charge. They also made parts available for older instruments for as long as humanly possible. We often bought their custom-made replacement parts for instruments which were 20+ years old. Besides the obvious fact that their instruments were/are such high quality, they offered truly outstanding support. This basically enlisted support techs like myself as an army of enthusiastic unpaid salesmen for their products.Notice that everything I wrote was in past tense. Unfortunately, in the late 1980's, the bean counters finally took over at HP and things changed a LOT! Almost overnight, they stopped providing complete service manuals, began a stated policy of supporting instruments only 5 years past last date of manufacture, charged $100 to expedite parts orders, and of course you could forget talking to one of their techs for support. Despite this grotesque new direction in their support policy, they had by that time established themselves as the premiere test instrument manufacturer. I think the reputation they established long ago has carried them on for decades. Even now, despite my resentment for their support policies they are my first choice for most things. Fortunately, despite the lack of parts availability, much of their 20+ year old equipment is still going strong.

author: Unknown
author_rank: Unknown
timestamp: January 27, 2012, 12:04:31 am
content: Quote from: JoeyP on January 26, 2012, 11:28:18 pmIs there any other vendor that's doing any better in this regard? I think HP was one of the last vendors supplying schematics. Discontinuing support as fast as they can get away with is also an industry-wide policy (ask Fluke how long their life time warranty lasts). They sometimes offer a best effort support for discontinued models, but I believe Agilent is doing the same. I know people have gotten software for discontinued logic analyzers and scopes from them. They also offer many manuals for old HP equipment on the Agilent website.

author: JoeyP
author_rank: Frequent Contributor
timestamp: January 27, 2012, 12:27:30 am
content: I don't know how others compare today, but I would guess they're all about the same by now. My intent was only to offer one possible explanation of why HP may have originally developed such a popular reputation (as per the thread topic). As I recall, Tektronix and others continued to offer complete service manuals for years after HP stopped. To be fair though, the era in which complete service manuals stopped being offered was also the period when troubleshooting to the component level became less and less practical due to more instruments becoming microprocessor controlled. Although the uC often made the overall circuit much simpler, they made troubleshooting dramatically more difficult due to the unknown of what's happening in software. HP tried to offer a solution to this problem with signature analysis. The concept sounds appealing, but it basically failed. I used signature analyzers on several occasions back in that time, and never once did that technique lead to the problem.

author: bsgd
author_rank: Regular Contributor
timestamp: January 27, 2012, 02:12:57 pm
content: Quote from: JoeyP on January 26, 2012, 11:28:18 pmThank you for all this information. In the 80's I was still a kid so I dont know exactly how helpful HP support was. I still think Agilent is pretty nice with service manual and schematics as they do seem to keep as much old equipment documentation available as possible.Quote from: JoeyP on January 27, 2012, 12:27:30 amThis is NOT good news. I have a defective 3582A Spectrum Analyzer here which I was expecting to fix, and I stopped troubleshooting exactly at the part where I need a signature analyzer and could not go on since I dont have one.I'm afraid I'll never be able to fix this thing, as Im not very experienced with this at all! OK, I'm going off topic here haha...

author: Unknown
author_rank: Unknown
timestamp: January 27, 2012, 10:31:27 pm
content: Quote from: JoeyP on January 27, 2012, 12:27:30 amMy impression is the opposite, Tek stopped publishing service manuals when the TDS DSOs were introduced, I believe there's a component level service manual for one TDS 500 model out there (probably something like a military contract). HP still produced schematics for many of their instruments through the early nineties. For example, the HP 33120A function gen, introduced in the mid nineties, has full schematics and theory of operations in the service manual. By that time the Tek service manuals were shallow leaflets with flow diagrams that almost all led to 'replace main circuit board'. Some current Agilent products still have a service manual with schematics or component level information package available (eg. 34401A, 3458A).Quote from: JoeyP on January 27, 2012, 12:27:30 amAgreed. One of the issues was new firmware revisions messing up the signatures. Getting matching manual and ROM versions can often be tricky outside factory service centers. Even some people inside HP found it useless.

author: JoeyP
author_rank: Frequent Contributor
timestamp: January 27, 2012, 11:08:55 pm
content: Quote from: alm on January 27, 2012, 10:31:27 pmThe early 1990's were exactly the period when the transition occurred. Since product development cycles are often years in length, anything already in progress (or for which there were already defense contracts) probably escaped the bean counters. As you mention, government contracts probably have a lot to do with some instruments having complete manuals while others don't. I think they actually had a lot to do with why parts for 20+ year old instruments were more common back then. There used to be some extreme support requirements written into defense contracts back in those days, but when we got all "lean and mean" with the defense cuts of the late 1980's things changed a lot as the government realized just how expensive some of its policies were. Of course the government never got to anything that could be called "efficient", but there were a lot of changes as it thrashed around trying.

author: JoeyP
author_rank: Frequent Contributor
timestamp: January 27, 2012, 11:26:40 pm
content: Quote from: bsgd on January 27, 2012, 02:12:57 pmWell, if it is a genuine processor-related issue (that is, power supply, clock and reset circuitry all verified) there's a pretty good chance it's a memory issue. I repaired thousands of instruments back in those days, and one thing that always impressed me was just how rarely a microprocessor actually failed - virtually never (unless it had a built in EPROM). However, memory fails often, particularly EPROMs. Most EPROMs are spec'd with something like 20 years data retention. Most will last much longer, but there are bound to be quite a few out there beginning to "forget" by now. Even masked ROMs were surprisingly unreliable. To the extent possible, I've backed up the EPROMs in all of the more prized instruments that I own. I've been able to replace masked ROMs with EEPROMs on several occasions (sometimes takes a slight circuit modification). Older RAM (particularly 2114's and predecessors) fail a lot too, but later RAM seems to be more reliable.

author: bsgd
author_rank: Regular Contributor
timestamp: January 29, 2012, 03:48:21 pm
content: My impression is also that HP offers much better service manual than Tektronix. I have succefully repaired a few old HP equipment using the troubleshooting section of the manual, whcile Tek manuals never helped me. So from a beginner point of view, HP definitely wins here.Quote from: JoeyP on January 27, 2012, 11:26:40 pmI will have to look into that. I am not very experienced with memory ICs, so I dont even know how to burn the data on them. The problem here is, if the memory is the one to blame, where would I ever find the ROM file to burn it? Also, how can you test a memory to see if its working? I guess you just replace it all ?!OK, lots of learning experiences to come! I have a few defective test equipment here and even if I cant fix them, at least I'll be able to learn form the experience. I'm young and not very familiar with how most test equipment works.

author: grumpydoc
author_rank: Super Contributor
timestamp: January 29, 2012, 11:29:33 pm
content: QuoteIf you are lucky and the ROMs are separate chips then in a working unit of the same type. If it's a mask programmed ROM inside the CPU then it might be a little harder....QuoteTake it out and put it in a RAM tester - assuming you can find one which drives that sort of RAM. In practice your suggested method may be the only one practical. RAM does sometimes fail in unsubtle ways though - eg a data output that is permanently low or high, as the bus is tristate that usually makes it easy to spot with a 'scope or logic probe. A data bus bit which is stuck at `1' or `0' has a duff chip on it somewhere.

author: bsgd
author_rank: Regular Contributor
timestamp: January 30, 2012, 11:37:50 am
content: A RAM tester? I guess I'll have to buy one.BTW, what burner and what programmer would you recommed?

author: grumpydoc
author_rank: Super Contributor
timestamp: January 30, 2012, 03:19:05 pm
content: QuoteNo idea whether you still can - you can get DIMM testers but whether you can get anything to test old static or DRAM I don't know.QuoteAbsolutely no idea I'm afraid - the last time I did this sort of thing was 20 years ago. When I was actually doing repairs we twisted the owner's hand into getting a UV eraser so long as I built a programmer - which I did for the 2708 - 2764 family which was pretty common in the stuff we fixed.It's all flash these days isn't it?

author: olsenn
author_rank: Frequent Contributor
timestamp: January 30, 2012, 03:42:23 pm
content: Just look at the brochures:Fluke: Some old white guy, wearing a hard hat, working in a factory where high volatges are used. This is the image Fluke wants... meters for the good ole, hard working american man who needs a handheld multimeter that will withstand many drops from the hands of the user, being chucked into a tool box, getting wet, being mis-used (connected to high voltage lines by mistake)... this meter doesn't need to be super accurate or have all kinds of advanced features; it just needs to do the basics, and be very reliable and last a long time. It costs more to pay for an engineer the 3 hours it takes for him to realize that the reason the meter is reading an unanticipated value is because of the meter itself (and not the device under test) than it does to just go out and buy a new meter.Agilent: An asian scienist wearing a lab coat and glasses, sitting at a computer, trying to figure out the effects of electromagnetic radiation on a liquid nitrogen cooled superconducter being surrounded by the element bismuth. The image Agilent wants is to be super accurate and precise and capable of doing anything anyone could ever want. Not to say they're not durable and reliable, but that's not the number one concearn of Agilent.In short, people who buy Agilent do so because they want to buy Agilent... people who buy Fluke do so because they want to buy Fluke... and people who buy Meterman do so because they want to buy Agilent, but can't afford to!

author: bsgd
author_rank: Regular Contributor
timestamp: February 02, 2012, 10:15:46 am
content: Well, that image thing does make sense. I never really thought about that, but burried somewhere in my head I do have that image of Fluke beeing the reliable industrial device while Agilent sits in a research lab shelf.