last Tektronix analogue scope without proprietary ICs? - Page 1
Forum section: electronics / testgear

author: smjcuk
author_rank: Frequent Contributor
timestamp: April 02, 2015, 08:14:39 pm
content: Does anyone know what the last line of scopes without any proprietary ICs and uC devices was? My ancient telequipment D83 scope is on the way out (timebase, amp and PSU problems) and has had too much CPR to carry on. Thinking about replacing it with a Tek this time.

author: Electro Fan
author_rank: Super Contributor
timestamp: April 02, 2015, 08:17:56 pm
content: Not sure about the last Tek scope made with out proprietary parts but this is a reference regarding the last of the fastest.http://w140.com/tekwiki/wiki/454"The 454 is the fastest general-purpose Tektronix scope that does not use proprietary hybrid circuits or proprietary integrated circuits....The 454 was introduced in March 1967. The 454A was introduced in 1971."

author: Vgkid
author_rank: Super Contributor
timestamp: April 02, 2015, 08:19:11 pm
content: I was going to say anything in the 400 series. Any reason why you want to avoid custom IC's. The 22XX are rathe reliable.

author: PaulAm
author_rank: Frequent Contributor
timestamp: April 02, 2015, 08:32:02 pm
content: Probably the 453/454 series. The early ones had nuvistors, but they were replaced with FETs in the later models. The 453a/454a also had a larger CRT.Getting tough to find the tunnel diodes for the trigger section though, but nuvistors are easy enough.453 -> 50 MHz, 454 -> 150 MHzI refurbed a 454 last year and the calibration only required some minor tweaks; not bad for a 40 year old scope. I keep it by my desk for when I need a quick look at something.The 46x series used Tek ICs, but they are not too hard to repair. You might need a parts donor for those, though.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: April 02, 2015, 08:34:00 pm
content: If you really want to stick to analogue, custom parts shouldn't be a purchasing criterion.AFIAK they were never particularly unreliable, just terminal on the occasions they did go. But that was back when they were in demand - nobody wants analogue these days so there are plenty of once-expensive scopes going for peanuts these days, and there will be parts available form scrapped units.And all analogue scopes have parts - the tube and the transformer.

author: tautech
author_rank: Super Contributor
timestamp: April 02, 2015, 08:36:16 pm
content: Quote from: smjcuk on April 02, 2015, 08:14:39 pmFix it.My first scope and a great design, reasonable easy to work on, most components can be substituted with better and beautifull crisp trace when right.I've got some component data and extender lead for the plugins if you need any.

author: smjcuk
author_rank: Frequent Contributor
timestamp: April 03, 2015, 12:12:24 am
content: Thanks everyone. Mangled replies...I've got the service manuals and I've fixed it too many times now. The transformer is on the way out (insulation decay), the tube has faded so you can see it in the dark on high brightness (even though voltages are ok) and the timebase capacitors are on the way out as are the pots. It's death by a thousand paper cuts now so I'm going to have to retire it. I paid £20 for it about 20 years ago and it was 20 years old then!Trying to get hold of something I can prop up for another 20 years hence no proprietary ICs. The D83 didn't have ANY ICs in it. I don't mind standard op amps, regulators, logic but nothing more. I had a friend with a 2225 that blew something expensive a few years ago. Quite reliable until they're not and the thing with the burn marks on it was a 14 pin DIP with "Tek" written on it.465 looks to be a good bet so far.After analogue because I tend to work entirely in the sub-50MHz analogue domain (as it's interesting).

author: nctnico
author_rank: Super Contributor
timestamp: April 03, 2015, 12:38:24 am
content: Perhaps hunt after an old Hameg. But like Mike already wrote: nobody wants analog anymore so you could get a good deal for a good unit and some others for spare parts.

author: smjcuk
author_rank: Frequent Contributor
timestamp: April 03, 2015, 07:17:47 am
content: Good idea with the Hameg. They appear to be pretty easy to get hold of in the UK as well.

author: oldway
author_rank: Super Contributor
timestamp: April 03, 2015, 08:32:02 am
content: I recommend the HM605 60Mhz bandwith with component tester, one of the best Hameg analog scopes.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: April 03, 2015, 08:50:27 am
content: Quote from: smjcuk on April 03, 2015, 12:12:24 amOld scopes will only get cheaper - why constrain your options based on a very marginal risk. Tube and PSU failure are more likely than a custom IC.Just buy the best you can afford & don't worry about it.

author: smjcuk
author_rank: Frequent Contributor
timestamp: April 03, 2015, 09:46:41 am
content: Quote from: mikeselectricstuff on April 03, 2015, 08:50:27 amHaving worked in a T&M department which got through piles of Tek 2400 series devices, I'm not so sure. Tubes and PSUs were pretty reliable. However blowing an ASIC appeared to be a special feature. This was Add to that, custom FPGAs and I can foresee a world of pain.

author: dom0
author_rank: Super Contributor
timestamp: April 03, 2015, 10:49:01 am
content: Probably 5000 and the slower ones of the 7000 series come without ASICs.

author: smjcuk
author_rank: Frequent Contributor
timestamp: April 03, 2015, 04:06:44 pm
content: Thanks - they look nice. Decent modular plugins.So those, a 465 (and a spare one for parts) or a Hameg are looking to be what's going on the watch list.

author: nctnico
author_rank: Super Contributor
timestamp: April 03, 2015, 04:54:58 pm
content: Still I think you would be much better off with buying a cheap Rigol or Siglent DSO. Those do not contain proprietary parts as well and the components run under less stress (no HV power supply, deflection, etc).

author: KJDS
author_rank: Super Contributor
timestamp: April 03, 2015, 05:00:42 pm
content: If you want an analogue scope without propriety parts, then Hitachi and Kikusui made decent models. I prefer the Kikusui ones for robustness.

author: smjcuk
author_rank: Frequent Contributor
timestamp: April 03, 2015, 05:13:30 pm
content: Quote from: KJDS on April 03, 2015, 05:00:42 pmThanks for the suggestions. Added to list.

author: smjcuk
author_rank: Frequent Contributor
timestamp: April 03, 2015, 05:15:50 pm
content: Quote from: nctnico on April 03, 2015, 04:54:58 pmApart from the big BGA packaged Altera Cyclone and the Lattice semi device in it...

author: nctnico
author_rank: Super Contributor
timestamp: April 03, 2015, 05:41:44 pm
content: True but by the time your next analog scope needs parts you probably won't find the parts with legs.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: April 03, 2015, 07:21:07 pm
content: Quote from: smjcuk on April 03, 2015, 05:15:50 pmThe Altera is not a proprietory part - - it's an FPGA that's loaded with configuration data on startup. In the unlikely event it failed, you could replace it (BGAness notwithstanding)Seriously, modern gear is reliable. Repairability is way less of a consideration than it used to be - less repairable, but much less likely to need repair.With modern digital scopes having intensity-graded displays, there is very little reason to buy an analogue scope these days unless you're looking for something really cheap. And if you're using it for any serious amount of time, a digital scope will usually pay for itself in time saved. Cheap tools are a false economy

author: grumpydoc
author_rank: Super Contributor
timestamp: April 03, 2015, 09:51:43 pm
content: It would be interesting to know which, if any decent speci (i.e >= 50MHz) analogue 'scopes are built entirely from "standard" components which are readily available today.CRTs and transformers are always going to be an issue, quite a lot of the Tek 'sopes used tunnel diodes which are hard to find, JFET input stages need fast protection diodes which can be difficult to replace and many later analogue 'scopes have CPUs with mask ROMs.Doubtless more examples of components which are hard to find nowadays can be thought of.I'd guess, but haven't verified, that the Tek 22xx series and the analogue Hamegs are a good bet for minimal custom silicon.

author: TheTek2
author_rank: Newbie
timestamp: April 04, 2015, 12:35:02 am
content: I own a TekTronix 2215A (60MHz) 2 channel analogue scope. I have the manuals ( service and operators ) for a few of the 22xx series. Excellent scope and remarkably stable even after all these years.Manuals are in pdf ... let me know if these would be helpful.I highly recommend one of these if you can find one. Definitely NOT selling mine anytime soon. Beautiful trace and easily maintained. Calibration a breeze but it does use old pot tech... only one or two exposed hi-volt point accessible even when opened in modular service.... Kelly.