Tektronix Surprise.

[KD1SH]

  Before I retired, my employer was throwing out...literally, as in dumpster...their old analog oscilloscopes, some of them reasonably current. They'd decided that they no longer wanted to spend money on calibrating them yearly. So, a couple of them came home with me, including a very nice Tektronix 2445A.
  It was a scope that I'd never actually used at work, and until today, I'd never really spent much time with it here at home, either. Powering it up, I connected a probe, and figured I'd take a look at the built-in calibrator's signal. Right off, there was the expected square wave, with exactly five complete cycles displayed across the ten divisions on the screen. I increase the sweep-rate, expecting one cycle to expand and fewer complete cycles to be displayed, but no...there are still five cycles on the screen. I increase the sweep-rate again, and although the on-screen display shows the increased sweep-rate, there are still five complete cycles on the screen. Huh? Maybe the time-base generator is stuck on one sweep-rate?
  A closer look at the calibrator terminal provides a revelation; the text next to it says "5hz to 5mhz"! Aha! The calibrator on this scope adjusts its frequency according to the time-base setting, so that five complete cycles are always displayed no matter where you set the sweep-rate.
  Discovering that was fun, but vaguely embarrassing because I can't help but feel that over a lifetime of working in electronics, I should have seen a scope with that feature before. Anyone ever use a scope with a calibrator like that?
  Embarrassing or not, I hope I never learn so much, or experience so many things, that I never run out of things I don't know.

[KA3EKH]

Been using Tektronix TDS family of products for years now. After you learn couple simple things like how the trigger works you get use to having a scope that displays things like frequency along with amplitude. Maybe the best thing of all is that when they develop a problem you don't waste time repairing them, you just throw it out and buy another. think I am on my second or third one now.

[W3JKO]

I had a similar situation in the early 2000's.  The Tek 2465A that I used at work everyday was due for calibration and I was told by our coordinator that the cal guys wouldn't calibrate it because they couldn't get replacement parts anymore and it wasn't worth it.  I used it everyday and knew what condition it was in and when the coordinator took me aside and told me if I wanted it to get it out to my car before it goes in the dumpster I didn't hesitate. 

There was also a time when the company bought Piezo crystal company and closed the facility and they had a sale for employees on whatever they wanted.  It was $3 for any item you could put on a cart.  I got a Delta temperature chamber, a few HP freq counters, a few bench supplies AND a fully functional calibrated HP141T for $3 each

[KD1SH]

  There was a time when "experienced" test equipment was available in vast quantities at large hamfests like Nearfest. This was back in the late 70's and early 80's, when the "Boston Sprawl" area was heavily populated with tech companies who were either moving out of the country, closing down altogether, or simply refreshing their test equipment inventory. Panel trucks, vans, and even trailers would pull into the fairgrounds loaded down with Tektronix and HP gear, often for great prices. Those days have pretty much faded into memory now.

I had a similar situation in the early 2000's.  The Tek 2465A that I used at work everyday was due for calibration and I was told by our coordinator that the cal guys wouldn't calibrate it because they couldn't get replacement parts anymore and it wasn't worth it.  I used it everyday and knew what condition it was in and when the coordinator took me aside and told me if I wanted it to get it out to my car before it goes in the dumpster I didn't hesitate. 

There was also a time when the company bought Piezo crystal company and closed the facility and they had a sale for employees on whatever they wanted.  It was $3 for any item you could put on a cart.  I got a Delta temperature chamber, a few HP freq counters, a few bench supplies AND a fully functional calibrated HP141T for $3 each

[KD1SH]

   When looking at certain analog signals, particularly amplitude modulated RF envelopes, I still love my old analog scopes, but yes, those modern  "Toys-R-Us" scopes are pretty spiffy. I used a Tektronix TDS series (I forget the model) scope for years at work, but when the trigger started to get wonky the boss didn't want to put money into getting it repaired, so I talked him into getting me a comparable Rigol, and I loved it.

Been using Tektronix TDS family of products for years now. After you learn couple simple things like how the trigger works you get use to having a scope that displays things like frequency along with amplitude. Maybe the best thing of all is that when they develop a problem you don't waste time repairing them, you just throw it out and buy another. think I am on my second or third one now.

[KD6VXI]

San Diego was similar.

Around the early to mid 80s all the vac tube and early solid state stuff from the Navy and Marine Depot was sold off by weight.  California Electronics, Delta, Murphys Junk and other junk houses bought it by the ton, warehouses it and then sold it piece by piece.

I was involved somewhat in California Electronics selling out to the Chinese in 1994ish.  Bunch of containers showed up.  Anything HP was NOT allowed to go in due to national security ( it was almost old vac tube based crap, this was in 94, get real!!!!!)...  but everything else went.  The last container they even swept the junk off the floor, and couple guys sifted dirt out of it, and they put it in a barrel!  Nothing stayed that didn't have to.

Sad.

We where allowed to grab whatever we wanted in trade for the labor of packing it all uo.  I think I still have a nixie tube Fluke DMM for the bench, maybe.

Funny, Murphys Junk is still open, expanded to another state, bought a communications distributorship and I recently bought NOS Astatic mics from them.  They where a block and a half from the place that sold out to China.


--Shane
WP2ASS / ex KD6VXI

[KD6VXI]

   When looking at certain analog signals, particularly amplitude modulated RF envelopes, I still love my old analog scopes, but yes, those modern  "Toys-R-Us" scopes are pretty spiffy. I used a Tektronix TDS series (I forget the model) scope for years at work, but when the trigger started to get wonky the boss didn't want to put money into getting it repaired, so I talked him into getting me a comparable Rigol, and I loved it.

Been using Tektronix TDS family of products for years now. After you learn couple simple things like how the trigger works you get use to having a scope that displays things like frequency along with amplitude. Maybe the best thing of all is that when they develop a problem you don't waste time repairing them, you just throw it out and buy another. think I am on my second or third one now.

Today's 'toys' are pretty amazing


I bought an Advantest (R & S) 8 ghz spec an.  Has a scope function in it!  I had zero idea i also was getting an 8ghz scope!

Also bought a cheapie OWON digital scope.  I like the fact it displays almost any parameter i want.  Frequency, duration, dmm accurate to 150 mhz, also has fft for doing spec an duty!

When I moved all my stuff here to the island I brought my Tek mainframe with me.  My wife just shook her head.

I showed her the difference between the display on the OWON vs the Tek analog, she immediately understood why the anchor had to come.

--Shane
WP2ASS / ex KD6VXI

[W3JKO]

  There was a time when "experienced" test equipment was available in vast quantities at large hamfests like Nearfest. This was back in the late 70's and early 80's, when the "Boston Sprawl" area was heavily populated with tech companies who were either moving out of the country, closing down altogether, or simply refreshing their test equipment inventory. Panel trucks, vans, and even trailers would pull into the fairgrounds loaded down with Tektronix and HP gear, often for great prices. Those days have pretty much faded into memory now.

At one time the company I worked for had a plant in South Carolina and the bottom fell out of the market and they mothballed the facility.  One of our managers took a trip to see if we could get any of the equipment for our plant.  He said there were literally skids of brand new HP equipment in the box that was headed to scrap.  We couldnt just transfer it within the company because it had to come off the books.  Now thats sad.

[KL7OF]

On the west coast, Boeing surplus was the place for cheap tektronix test gear..  The gear was made in Portland OR and Boeing is in Renton WA.  Boeing bought lots and surplused it regularly. Toward the end of the analog era it went by the pound.  I have a tektronix scope on the cart with 7 different plug in modules and I still am learning about all the things it can do...I also have a Nano VNA and a mini scope... covers all that I am capable of measuring...I wonder how many tubes are in that tektronix scope?  I'll have to look, I have the manuals...

[Tom WA3KLR]

One thing that can trip you up on those Tek scopes that change the calibrator frequency along with the sweep rate is when you do the probe compensation, you want to be on a slow sweep that gives around a 1 kHz. square wave or a little lower. Turning the probe compensating cap at high sweep rates, the displayed square wave will just go up and down in amplitude with no leading-edge shape change.

[KD1SH]

  Yes. I always figured the 1khz square wave was chosen as the standard calibrator frequency with good reason. I also noted that at higher sweep rates, with the calibrator frequency accordingly higher, my observed square wave showed some notable ringing artifacts, as if the calibrator's square wave wasn't quite as clean at higher frequencies as it was at lower frequencies, leading me to question whether my probe or the calibrator caused it.
  I had planned on exploring that, and posting my findings, but then I discovered why that scope had been sitting on a shelf out in the back room: it stops operating after it warms up for a few minutes. I've got the service manual, but for now it'll go back into storage until I get a few more ongoing projects off my plate. It's still a nice scope; one of the last hangers-on for Tek's analog models, with the TDS series looming on the horizon. I think that by the time the 246x series hit the scene, the sun was setting on analog/CRT scopes.

One thing that can trip you up on those Tek scopes that change the calibrator frequency along with the sweep rate is when you do the probe compensation, you want to be on a slow sweep that gives around a 1 kHz. square wave or a little lower. Turning the probe compensating cap at high sweep rates, the displayed square wave will just go up and down in amplitude with no leading-edge shape change.