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I have a 2467, which is basically a 2465A with a microchannel plate CRT, and an old 475. Both get used occasionally, but not very often these days.

Cheers

Phil Hobbs

Probably a 7104 with the MCP CRT.

Cheers

Phil Hobbs

Yup. The 485 is a bit faster but nowhere near the same build quality.

Cheers

Phil Hobbs

It uses tunnel diodes in a set/reset mode. There are some fine adjustments detailed in the service manual that may resolve your trigger issues. It could also be a bad tunnel diode. Does the B sweep trigger ok? Is it just an issue with triggering on the channel display or does it work with the line mode or external trigger mode?

The best thing is that the trigger board is easy to get to.

They are a little harder to find, but no arguments otherwise.

I'm trying to recall which Caig lubes you use on these old scope. One of these

On the old scopes, switches do more than flip relays. You need them to be clean and lubricated.

Tektronix says never use anything but isopropyl alcohol. The contacts are driven by a cam drum and are very delicate. I use strips of paper cut from an index card into 1/8 inch wide strips. Dip in the IPA and pull through the contact with it in the closed position. It does take some time but worth it.

I have that problem in my (currently shelved) 475; my problem is the TRIG POL switch (YMMV). When it's not working, trigger simply goes down, regardless of TRIG LVL position. Wiggle the switch and it starts working again. Sometimes, for a little while.

Various things have been replaced already; new CRT, electrolytics, the B DLY pot (the original 10-turn broke after a fall; I prefer the speed of a single turn pot anyway!), those little attenuator modules, etc.

My TDS460 seems to be doing well, but after having replaced every single damned radial SMT electrolytic. The electrolyte they used back in the day was nasty stuff.

Tim

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

Hard to tell, not so many anymore to choose from. Just some ideas.

- Iwatsu still makes analog scopes (300, 400, 470MHz). Never asked them for a price quote, but likely outrageously expensive

- Hameg and GW-Instek (Taiwan) used to make 200MHz analog scopes until quite recently (look for distributors with old stock). They still make 100MHz versions. Not really cheap (compared with Chinese no-name brands), but probably not outrageous.

- Xinjian (China) makes 100MHz (XJ4362A) and 150MHz (XJ4383) analog scopes, unfortunately not at all cheap. Also they make a (way too) expensive 300 MHz version (XJ4393).

- EZ-digital (Korea) makes some 100MHz versions with and without numeric CRT readout for dV, dt, 1/dt. They used to make a 200MHz version too, but not anymore. Not sure about prices, but looks more or less GW-Instek-like.

- Some no-name brands in China have analog scopes, factor 3 cheaper than Xinjian, but they rarely go to 100MHz. Mostly 40MHz is the norm and 60MHz is the upper limit. Whether they actually ever reach their stated ratings, no way to tell.

- Then there's always fleabay and various used equipment dealers :)

Rergards Dimitrij

P.S. I use a XJ4362A, bought 2012. On the good side, the power supply is linear, so EMC-wise quiet. Nominally 100MHz, but has no intentional filtering (only amp limitations), so will display 200MHz sine with a lower looking amplitude. Has a CRT with nice sharp traces, quite unlike a typical Chinese scope. On the other hand, some gotchas with some "getting used to": Timebase A/B trace separation won't go all the way across the screen height (Channel "Y-Pos" trace positions will go anywhere, but the difference between the traces of the same channel on both timebases won't be able to span the full screen). At full 100MHz signal, the Y-amp won't drive the trace all the way across the screen height, so better set the Y deflection to about half screen peak-to-peak to avoid some dV/dt amplifier limitation at the upper end of the frequency range. Apart from this, mostly OK. The user manual has full component-level schematics and some test point reference voltages with instructions how to adjust, but in Chinese only (well, component names still use english letters).

Install an add-blocker and add domain names to your 'hosts' file (google that) and you'll get rid of all advertisements. Works like a charm.

Mine has started making arcing noises - had a look but can't see where it's coming from. So it is on the "fix it one day" shelf for the next 20 years I expect :(

The first 7104s came back from the customers, one with a serious CRT burn-in (that the customer complained about). On further inspection it was noticed that there was still some residual adhesive stuck on the front panel where the beam-current-reset button had been held down. I think management still gave them a new CRT, though at the time (late 70s) the early production MCP CRT probably cost $10K to make. I don't recall whether they changed the reset function to be edge-sensitive.

The bandwidth was great, but you could have more with a sampling scope. What distinguished it was the writing rate, which was orders of magnitude faster than anything else at the time. In that era the fastest digital scopes topped out < 100MHz - obviously it's very different now.

It could be failed start-up attempts of the power supply. There's some weird stuff in there, like pre-blackened neon bulbs.

It actually *works* fine but it is not a good noise to be making I would think. I assumed around the EHT but can't see anything - even with the covers removed and room lights off :)

The redneck approach would be to simply let it hiss until one mornin' "it's gitten smokey and it don't work no more" :-)

I assumed around the EHT but can't see anything - even with the

Probably better to use plastic tubing and a mike into a sound card, to try to locate where the hiss is coming from. I find that waterfall patterns in a software like this work best for finding stuff because almost everything has a spectral footprint:

I don't think any of our shoe-box-sized digital scopes have any pre-blackened neon bulbs inside.

Seriously, all those old tube scopes are getting hard to maintain. And a nice Rigol costs under $400, with probes.

I do have a modest collection of Tek 547s, the best of the old

That's what I do.

Tek cam switches have little,if any wiping action. Lubrication is neither necessary, nor desirable, on the contacts. A minimal amount (just a smear), of good mineral grease on the cams is a good idea.

A little grease on the end bearings will slow down the inevitable progress to eccentricity, which is a "feature" of those switches.

Full of unobtanium ICs and hybrids. Everything under processor control. Front panel controls and analog calibration settings muxed, demuxed, sent out, queried, sent back, and recycled as firelighters. Apologies to the Vogons;-)

Probably the worst oscilloscope headache I ever had.

That's much more to my liking. I've got several. Much easier to maintain than 2465/2467.

If you *must* have a 2465, get an early one (S/N

Once you've worked out whether it's really there, or some sampling artifact;-)