#1) Tool_maker: One point... When I referenced having Instruction Manuals & complete schematics, I'm referring mostly to equipment manufactured in the post WW II era into the 1960s & early 1970s, although we did have some RLC Bridges that dates to the WW II era. Today, the phrase "Customer Service" should be stripped from the lexicon since there's hardly a major manufacturer of products, whether capital equipment OR consumer products which offer an expected level of care. Even government agencies aren't immune to this "couldn't care less attitude" that has permeated society in general!
#2) Ed from the TEK Museum called me personally to apologize that they were not able to repair that TEK scope. Now, THAT IS Customer Service!!!!!
#3) To OLDTIMER8080.... I agree..... JANUARY IS looking better & better every minute of the present work week. Getting the best of both worlds for the applications that I foresaw was the main reason for selecting the TEK 2465B scope. I really didn't need the 4 channels, or the 400 MHz bandwidth, but the digital storage capability seemed to be a useful function for certain times when I needed to capture a signal. We bought this scope used & refurbished, and it wasn't used on a daily basis. There were many periods of inactivity where it sat on an old TEK rolling cart.
At one time I was a member of a local model R/R cluvb. One of the members was a retired engineer, who had a "warehouse" on his property. He invited me there once. I LITERALLY filled the back compartment of a FORD WINDSTAR mini-van with old TEK scopes...... 547,525, etc. AND carts AND separate Power Supply chassis AND Plug-In amplifiers of all descriptions. Most had major problems, but I didn't have the time, documentation, or facility to delve into their repair, and so unfortunately, the ONLY parts to survive are several of the CRTs themselves, as decorative items. All the carcasses wound up in the dumpster. I truly wish I had known about the TEK Museum when this disposal occurred because I'm sure they would have relished this treasure trove.
How quaint that you actually recieved owner's guides and manuals with your purchase. I gripe about lack of same with software on a daily basis. Thankfully we hired a new guy who inherited my Solidworks seat so I no longer am frustrated by that monstrosity, but our latest AutoCad upgrade did not even include a disk. We are supposed to download it over the net. I finally got to talk to a real person and was told they only supply disks on request and it takes 7-10 days. It has been three weeks and I still have not received the upgrade. Then to add insult to injury, they have a subscription service for support.
I remember when companies actually did provide customer service. Does it not seem that as competition gets greater, service would be a priority? Arrogance and "take it or leave it" is the new normal. My upcoming January retirement sounds better and better.
I REFUSE to allow a digital scope in my lab. As someone who specialized in high speed signal issues, I know that the SAMPLE & HOLD requirements are key to any digital measurements.
That is the nasty little secret that digital scopes have. If you are trying to nail down an intermittent problem, a digital scope is BLIND during the hold of the measurement it displays ( called sample & hold in the data sheets for an IC device ).
That is why I have the same model scopes I worked with at Cray Research in my lab. I also managed to keep a pair of older 525 type scopes ( with carts & plug-ins ) still running.
Yeah, I know the microwave plug ins suffer from a similar sample and hold problem, however I see the actual results on the display and not a " fudged " one on the digital equivalent of my 7104 and 7904 scopes.
Since I grew up fixing old tube type TVs and built my own Heathkit test gear, I think I might know my way around those old tube type jobs..
BTW, I was a calibration tech fixing the $5 million test systems for AMD, so I'm familiar with fixing AND calibrating stuff to Mil-Spec standards.
Since Boulder is about 50 miles away and home to NIST, I could operate a fix & calibrate lab...
Discrete components are still available. No break & throw away for me!....
Ah, memories! The first scope I ever used on the test bench was a TEK 535/545 on a rolling cart. Ran at the amazing speed of 18 Mhz! It was also good as a small space heater, but solved many an analog problem for me!
Well, I'm sorry to disagree with you, but I believe that they ARE selfish in that they discontinue product support too early for a piece of capital equipment such as this scope. We're NOT talking about a consumer product which may have a limited life by its very design. When I began my career in electronics 50 years ago, we had some of the most advanced test equipment of its day in our laboratory group, and ALL the equipment had Owner's manuals & Service manuals which were kept in the Engineering Library under strict control.
While I'm NOT denying that modern-day test equipment IS far more complex than the equipment I "cut my teeth" on, nevertheless, it seems to me that there SHOULD BE more direct factory resource for replacement parts over a longer period of time. Furthermore, my comment about TEK was not of my own design. I've read many blogs over the years, and TEK has gained a reputation for abandoning many of their former products. Additionally, when I sent this scope to the repair facility for diagnosis, the manager of the office called me with the result. It was his words on the phone that added more credence to the negative comments that I've read in other places.
Finally, while the site that you referenced may be a source for certain items, IF the fellows who run the TEK museum in Oregon, and who WERE long-time TEK employees were NOT able to repair this model, then I would think that I exhausted all the viable avenues. I'm sure they're aware of every source for TEK replacement parts.
p.s. For your information, here's a copy of the e-mail that I received from the fellow who runs the TEK museum..... I highlighted the one important sentence in his response to my intial e-mail.
We repair customer's scopes for donations to the museum, most local customers, but those that wish to pay shipping in both directions for their "special" vintage instruments. We will go thru the instrument and give you a quotation for repairs (if it can be repaired). Some of the newer stuff have proprietary integrated circuits which are Tek made and no longer available.
I would not characterize Tek as selfish, it's just that the complexity inside the scopes is getting to the point where component level repair is almost impossible. BGA chips, fine pitch PQFP. It isn't like the good old 16 pin dip days. Even at Tek, for the most part, PCB replacement is the normal repair route.
As for 2465 ROMS, the Tek scopes Yahoo groop would have been a good resource. Steve Lindberg
The older TEK scopes were workhorses & for the most part could be repaired should some component fail. However, in recent times, TEK has taken a more selfish road in my opinion. The last scope we had in our area was a 2465B, 4 channel, 400 MHz unit. It was a great scope, having the ability to save waveforms in memory & do some other advanced functions. However, in a recent event, we were analyzing the outputs of some bench power supplies for steady-state ripple. On day one of this investigation, all went well. The following day we powered up the 2465B, and it would NOT complete its POST. In desparation we called a local office (national) repair facility. They analyzed the scope, and claimed it was unfeasible to repair since the repair would be as high as purchasing a reconditioned one. So, knowing about the TEKTRONIX museum on the west coast, we sent it to them for analysis & repair. They traced it to a PROM chip, but could not repair it due to the propriety of the code. TEKTRONIX no longer supports this model, so we are now scopeless. The museum's terms are such that IF they cannot repair a scope, you can donate it to them as a parts source, and that's what we elected to do.
Every diode is different, of course, but the reverse breakdown voltage is about 5V, and the diode can be damaged by currents in the microamp range. So, if you have a 470 Ohm current limiting resistor in series with the LED and then you reverse the the current, the diode will breakdown and be damaged by the 10mA current.
I shorted one this way, and it did rather surprise me.
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