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I'll carefully tread into this whole "are analog scopes worth having anymore?" discussion.

This thread's originator said "I've never used an oscilloscope before." With that in mind, I recommend he START with an analog scope. You can often find them on Craigslist, eBay has lots of them, and (since his username looks like a ham call sign) hamfests commonly see a few and/or local hams may have one they're willing to part with. Plus he has an offer for a FREE one, doesn't get much better than that.

Don't view this as "No, I don't want it. It will set the day I get a proper scope back even further." Buy the digital scope on the same schedule you had planned. But LEARN about scopes by starting with the analog unit. Why? Because you will be "closer" to the signal with the analog scope. Digital scopes, with their sample memory and triggering that moves around within that memory, add layers of abstraction that you don't suffer with an analog. Analog scopes also have things I don't often see on digitals, like linearly variable amplitude and sweep. You won't spend lots of time on them but they are immensely valuable in acquiring a gut-level, intrinsic feel for how a scope actually works. The analog scope doesn't need to be in calibration. It doesn't even need fancy features. You need a horizontal sweep, a vertical amplifier, and a triggering circuit. Just those three things will teach you more than you realize, and all of that deep understanding will transfer directly to your new digital scope and make you far more proficient with it. Remember, you said "I've never used an oscilloscope before." The more, and easier, you learn about what a scope actually does, the better you will be at using ALL scopes.

If it were me, I'd fire up the analog scope, switch its trigger to Auto, and put some repeating signal on the input. Even just the scope's own integrated square wave (used for calibrating probes) will work. You'll see a scrolling waveform on the screen. Play with the vertical sensitivity and get a feel for what happens on the screen. Play with the variable sensitivity knob too.

Then play with the horizontal timebase. See how the waveform's visibility changes as you speed and slow the sweep rate. There will be a point where, perhaps with the help of the variable sweep knob, you can almost kinda sorta get the waveform "stable" and see its shape.

This is already more visibility than you had with no scope at all, and even if you don't realize it you're training yourself to treat the scope not as this discrete "tool" but as an extension of yourself. Like wearing glasses, eventually you don't think about the tool and the tool just becomes part of YOU. You're already using two of the main sections of the scope.

Now, it sure would be nice if you could stabilize that waveform on the screen, right? So it would stop moving around and you could really examine it. That's what the third main section, the triggering system, does. Switch the triggering system to Normal. If the screen went blank, don't panic... the triggering system will only let the trace move across the screen if the input voltage crosses the trigger level threshold. Now try varying the trigger level until the trace (re)appears. Note that it's stable now! The trigger system only lets the horizontal sweep occur when the input voltage crosses the trigger voltage level. You change that voltage with the trigger level knob.

If you have access to a sine wave (this example doesn't work well with a square wave - can you figure out why?), use that and vary the trigger level. You'll see the sine wave move left and right as you change the trigger level, because as you change the trigger level it matches the sine wave at different places. Also try inverting the trigger slope. See what happens to the waveform on the screen.

Now, find another signal source. Maybe a serial data stream, like RS-232 or CAN or USB or something. By using Normal trigger mode you will probably be able to get a psuedo-stable display, and by varying the horizontal timebase you should be able to fill the screen width with roughly one byte/packet. The waveform may be changing, but that's just the varying bits in the data stream.

Now, without changing anything else, switch to Auto trigger mode. Lots of horizontal scrolling now, right? Can you explain why? Hint: Auto mode just mindlessly starts the next horizontal sweep when the previous one finishes. How does Normal mode differ from that?

Play around - and I really do mean PLAY - with the analog scope like this, looking at every signal you can find. An hour or two of this and you'll develop an innate sense of how to tune the scope to the signal. You won't look for the "right" button or knob, your fingers will just go there. You'll stop thinking of the scope as separate from yourself, and start thinking more about the signal you're investigating. And all of this will transfer directly to your new digital scope. You'll be more proficient with it, faster, than without the analog scope experience.

Could you do this starting with a digital scope? Sure. But it is my humble opinion that it will take you longer to become equally proficient, and you miss out on the "scope zen" that you'll quickly develop with the analog scope.

I could go on and on, but hopefully you get the idea. Hope this helps!
Have you experimented at all with some high power HF signals? I have my 3458A's a decent distance from my HF rig and amp and the antenna is on a small tower but keying up with even 100 watts on 20 or 40 meters does cause changes in my measurements. I won't even get into what happens when I tx with a kilowatt.

Radiated RF from the Radio, Amps, feed line is almost no issue at all as tested in to a good dummy load (Palstar DL5K), radiated RF from the antennas, even though they are on the other side of the house is an issue.  Depending on what I'm doing I stay off the radio.   Especially 2m/440 with the handheld in the shop.  I fought trying to keep RF out of my 10v reference, got it down 5' distance at half a watt was okay, best I could do.
"- a repairman usually does not keep the defective parts to avoid mixing them with the good ones.

Again I agree 100%. Most, nearly all, of the testing of components I do is to see if they are suitable to go into the spare parts inventory. In rare cases, they have to be ordered in for a specific repair, but even so I tend to test them first. Like a dog chasing his tail, I learned that "new" parts can be bad.

One time I bought a bunch of 7 segment LEDs from a local surplus electronics joint. Several were bad so next trip I returned them, which they gladly replaced. On the way out the door I noticed they threw the bad parts right back in the bin with the new ones!

Metrology / Re: Peltier enviromental chamber builds
« Last post by ch_scr on Today at 06:26:28 am »
I finally managed to get my basic control & driver circuit to work. Guess who learned the hard way how important seperate regulation for load and control supply rails is when driving bigger loads  ::) I tried to create an "elemental while reasonable" analog control circuit for my box, while designing from stock. The current mirror is in there like that because i did not have another OP07 at hand at the time.
I use an old CATV head unit power supply that has sturdy a 12.5V line to drive the Peltier, the 18V provides positive control rail and the 5V provide the -5V control rail via an isolated DC-DC module. It works reasonable for a first attempt, slight overshoot on the regulation but nothing serious. I literally just had success an hour ago, i tried alot to get it working on +12.5V alone and it would not stop oscillating |O Build pictures: The fan and big heatsinks are a mix of legacy, what was at hand and a safety measure to protect the mosfets. Sure did prevent me from blowing them up while messing around.
For those vials, what does this spec mean?

Accuracy: 4"/2mm

Circuit Studio / Circuit Studio new release 1.5
« Last post by jmarkwolf on Today at 06:17:59 am »
The new version 1.5 has been released.

It's kinda anemic as far as new releases go, but it's better than nothing.

Some menu bar items have changed. You need to select a "category" in the filters before you can actually select anything in the database. Kinda works like a dumbed down "Find Similar".

Also, be sure you're aware of the menu items you're selecting or you can get thrown off. I was selecting menu items by "location memory" and inadvertently selecting the wrong functions. 
Test Equipment / Re: Siglent SDS1104X-E In-Depth Review
« Last post by tautech on Today at 06:14:13 am »
Neither of my 100x probes have ground springs but the metal sleeve comes all the way to near the tip like any other probe.

The 1000x 8KV one I have has a long fixed reference lead and NO grounding anywhere near the tip:

Here's the 1kx on the Probe Cal SDS1104X-E

Normal acquisition

Averages engaged
Good points, thanks Gyro. Yes the dial is held in place by screws. There are two different versions of the dial, both are easily hackable. Soon I'll post my 4 wire resistor standards build, made with 5 and 10 Dollar eBay finds. (mil spec Vishay metal foil resistors).

Not volt-Nuts standard but way better than anything I had before.
Precise title Joe.  :-+  Ok, I'm in for some reading/learning..
I think there's a luck element. Mine is still going strong after 7 years, and i haven't been too careful about alignment or cleaning. I haven't applied any grease.

The cable is doing OK because I'm really careful when I store it.  Those fold-out white ears you can allegedly wrap the cable around are worse than useless in my book.

I wish Apple would select a slightly more durable cable jacket and really up their strain relief game.
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