[HN Gopher] Dumpster Tektronix 2465B Restoration
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Dumpster Tektronix 2465B Restoration
Author : sunestra
Score : 68 points
Date : 2023-09-22 15:27 UTC (7 hours ago)
(HTM) web link (sunestra.fr)
(TXT) w3m dump (sunestra.fr)
| prpl wrote:
| These guys were very nice. I have the 150Mhz digital version in
| excellent condition I got from the salvage docks in college.
| jeffbee wrote:
| I have the DMS edition with the 4.5-digit multimeter, reads
| down to 10uV and has the GPIB. A damn handy combination of
| options. A comparable modern Fluke costs $1200. I found this
| one on a curb.
| CommieBobDole wrote:
| "Positive level too positive" is my new favorite error message.
| monocasa wrote:
| I've been to company all hands meetings I would describe as
| that.
| justsomehnguy wrote:
| Oh you!
|
| Then I take "Positive level not positive enough", it has the
| same vibe as "... until morale improves"
| gedy wrote:
| Same model I used in the Air Force, this brings back some
| memories
| 0xbadc0de5 wrote:
| Used to own one of these back in school (cheap off eBay). Was out
| of calibration but still served my needs and was a great scope
| all round. My only regret was getting rid of it.
| arcticbull wrote:
| I've got a 465B in the basement that I've had for years now, I
| should dig it up and calibrate it. Came with the manual and
| schematics and everything. There's something really nice about
| using analog scopes.
| monocasa wrote:
| > There's something really nice about using analog scopes.
|
| There really is, and it's not just hipster-esque nostalgia like
| people who haven't used them might think.
|
| For one they're not subject to digital aliasing. Sure, they
| have some bandwidth limitations that can lead to some of the
| same results, but I've found they're better at smearing the
| different frequencies on the screen when I'm looking at the
| scope with not ideal time steps, whereas it's far easier on a
| digital scope to get something that looks like your signal but
| is just an artifact of the digital aliasing. There's a lot of
| nice features that a DSP pipeline unlocks versus an analog
| pipeline, but sometimes when things get real wonky it's hard to
| beat an analog scope to make sense of reality.
| ChrisMarshallNY wrote:
| This is a great write-up.
|
| As a former user of these (and many more expensive ones), I can
| tell you that the most problematic thing is ensuring calibration.
| We used to have a lot of very expensive stickers on our kit.
|
| One of the advantages that digital has, is that calibration is
| pretty simple; an A/D step, and then everything after that is
| gravy.
| dfox wrote:
| Well it is probably somewhat depatable as to how much one
| should care about calibration of an CRO, especially today. The
| precision is somewhat inherently limited by what you can
| resolve with Mk1 eyeball on the screen. I have an 4 channel
| Kenwood CRO on my bench that is intentionally completely out of
| cal as removing the burned out vertical amplifier gain hybrid
| modules (complete unobtanium, although one might be able to
| handcraft that as a SMT board with modern components) makes the
| thing work for some value of "work" (no vertical vernier, the
| cal position being on the order of 2x off). But well, it works
| for looking at powersupply noise in relation to digital signals
| and similar stuff.
|
| In contrast to that one somehow expects that on a random
| digital scope functions like measurements work and are
| reasonably in-cal. And the calibration on digital scopes tends
| to involve possibly undocumented software, not turning trimmer
| pots/caps of obvious function while having tongue at a right
| angle.
| ChrisMarshallNY wrote:
| I worked for a defense contractor, at that time, and
| calibration was _extremely_ important.
|
| Also, NIST (I think they called it "NBS," back then) was,
| literally, across the street from our company.
| dlevine wrote:
| Back when I was in college, people would go dumpster diving for
| the really old analog oscilloscopes with the green tubes. They
| would hook them up to their stereos in spectrum analyzer mode.
|
| We would use the ones like this to actually do work in lab.
| rkagerer wrote:
| Awesome! I've got an old analog Tektronix scope on my desk that I
| still use regularly. And if I recall, I had to replace a
| capacitor or two on it as well some time back.
| dark-star wrote:
| Man, I envy people who have dumpsters like this around...
| seabass-labrax wrote:
| The same for me! My local refuse centre does not allow anything
| to be sold or given away once it enters the container for
| disposal. This is for safety reasons, but it is rather sad:
| reuse > recycling.
| petercooper wrote:
| A couple of years ago me and my mother were responsible for
| clearing out my dad's entire collection of equipment
| accumulated over a career as an electronics engineer. I know
| much of it had value but there was too much to deal with so we
| sold a few obvious items and gave away the rest to someone on a
| local Facebook ham radio group who could drive round and take
| it all away. There was certainly a Tektronix oscilloscope like
| this among it! (Along with spectrum analyzers, test sets of
| various vintages..)
|
| I'm not sure of the best way to find such opportunities, but I
| bet there's plenty of kit like this getting thrown out when
| people's affairs are being put into order by their relatives.
| It gets me to thinking I should add some tips in my will as to
| where to give away _my_ technical odds and ends(!)
| HeyLaughingBoy wrote:
| A good place to start is your local auction house. They are
| often tasked with disposing of people's estates. Technical
| stuff usually goes for pennies on the dollar since nobody
| knows what to do with it.
| HeyLaughingBoy wrote:
| You gotta work at the right places :-)
|
| Years ago we senior engineers stood around while an intern was
| in the dumpster grabbing stuff for us so we didn't have to get
| dirty. "No, the other gantry: it's got a bunch of really good
| stepper motors on it," "Yeah, I can find a use for that big
| slab of aluminum but you can keep the PLC's if you want..."
|
| Seriously, my boss said to me one day "I know you're kind of a
| pack rat and we're throwing out a robot arm. If you want it,
| call Facilities and have them load it into your car."
| iancmceachern wrote:
| One time I got a whole entire commercial portable AC unit.
|
| Just gott be there at the right time and have a pickup.
|
| I stopped getting the "parts" kinda stuff a long time ago, I
| have enough motors/gears/ics in boxes. Now I limit myself to
| things that work or can quickly be made to work, and have an
| immediate application in our home.
| neilv wrote:
| When I worked at a Tektronix spinoff company, one time they were
| clearing out a lot of bench equipment, using a blind auction
| instead of the Dumpster.
|
| Among my haul, I got two large logic analyzers, for $5 apiece,
| free of Dumpster commingling artifacts.
|
| (This is both a happy memory, and an embarrassing one. After I
| moved the loot to my cubicle, before figuring out how to get it
| home without from the rural-ish science park without a car, one
| of the hardware engineers came by my cubicle, and was admiring
| the logic analyzers. Being a dumb teenager, with little
| understanding of adult interactions, I didn't realize until
| years/decades later that he might've wanted one of the logic
| analyzers, and I should've offered.)
|
| Years later, I was a grad student, and, amidst a pile of junk in
| a common area of the lab that was being cleared out, was a NeXT
| Cube, which someone said I could take home. So I had it in my
| office (again, no car), and then another grad student comes by,
| and says they'd already claimed it somehow, so I gave it to them.
|
| Generalizing from two anecdotes: keeping things out of the
| Dumpster is good, methods are unfair, and, if you score discarded
| gear from your workplace, then exfiltrate it immediately, to
| avoid awkwardness.
| NKosmatos wrote:
| Nice write up and gorgeous find. Reminds me of the Tektronix
| analog oscilloscopes we had a few decades back when I was at
| university. Great machines, built like tanks and guaranteed to
| work for many years as opposed to the modern expendable digital
| gadgets.
| pvarangot wrote:
| "guaranteed to work for many years" if you don't need them
| calibrated I guess.
|
| Also like I'm not sure? A lot of the discrete component and
| analog stuff on the old models is way more flimsy that the new
| system on a chip things on the signal path of the new
| instruments, specially for RF.
|
| Plus if you need data logging it's not even worth to have the
| discussion on if older gear was better.
| mikeInAlaska wrote:
| It may actually prove to be the opposite case as the capacitors
| in these old scopes self destruct and eat their own circuit
| boards and surrounding components.
|
| I have a Rigol and an Agilent over 10 years old now and going
| strong. Honestly though, my Agilent overheated once and
| destroyed its own SMPS. This was terrifying given the price of
| the scope (and at the moment, just knowing -- it was dead and
| smelled like an electronics fire). I now have a circulating fan
| on my scope shelf moving air behind and across all my bench
| equipment.
|
| I replaced that Agilent SMPS for $150? and then got a 2 year
| service plan for another couple hundred dollars.
|
| The latest Rigol prices are pretty expendable, $299!! but I
| suspect they will be running for quite a few years.
| Pixelbrick wrote:
| Awesome find, the author is lucky indeed. I've got a 2465 (no B)
| that I love dearly & have spent too much time & money on.
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(page generated 2023-09-22 23:00 UTC)