Beginner Oscilloscope Best Approach to Purchase Now or Later?

[Lowkus]

Careful with that. A house is an investment, an oscilloscope is a depreciating asset, especially if you are not using it to earn a living.

I bought a small house toward the end of 1999 (or maybe it was 2000... my memory sucks these days), a couple years later I damaged my tendons from working too much and was forced to sell everything at a loss.  I would have made nearly a million USD if I'd kept that house, so I'm very cognizant of how profitable it can be to own a house.  The problem with housing around Puget Sound nowadays is that we've had an insanely huge influx of wealthy tech workers coming to the area for the last two decades, with more coming every year.  The housing demand is crazy and the low interest rates have only pushed home prices higher.  A single-income worker like myself can't afford the kind of house I want to live in.  I've also gotten tired of the darkness, crowded roads, unfriendly people, homeless masses, and increasing crime that's been growing in this region.  I'm hoping in the next few years to find a new area to live where the quality of life is better and more affordable, and I'm also trying to start my own business so I can stop being dependent on an employer who provides what is effectively an unreliable and dwindling income source.  The electronics projects I'm planning will be for commercial products for my business.  The oscilloscope will be a depreciating asset but I don't mind that, so long as it gets me closer to escaping the day job.

[james_s]

I bought a small house toward the end of 1999 (or maybe it was 2000... my memory sucks these days), a couple years later I damaged my tendons from working too much and was forced to sell everything at a loss.  I would have made nearly a million USD if I'd kept that house, so I'm very cognizant of how profitable it can be to own a house.  The problem with housing around Puget Sound nowadays is that we've had an insanely huge influx of wealthy tech workers coming to the area for the last two decades, with more coming every year.  The housing demand is crazy and the low interest rates have only pushed home prices higher.  A single-income worker like myself can't afford the kind of house I want to live in.  I've also gotten tired of the darkness, crowded roads, unfriendly people, homeless masses, and increasing crime that's been growing in this region.  I'm hoping in the next few years to find a new area to live where the quality of life is better and more affordable, and I'm also trying to start my own business so I can stop being dependent on an employer who provides what is effectively an unreliable and dwindling income source.  The electronics projects I'm planning will be for commercial products for my business.  The oscilloscope will be a depreciating asset but I don't mind that, so long as it gets me closer to escaping the day job.

Ouch. Yeah it sounds like you're in the same area I am, and I've observed the same thing. Thankfully the particular suburb where I am is still very low crime and I haven't seen any homeless people around here at all but Seattle proper is kind of a dump these days unfortunately. I'm all the more glad I bought when I did because there's no way I could afford to live where I do now if I hadn't. My house has become absurdly valuable which sounds great until you realize that my property taxes are correspondingly absurd and it's wealth only on paper, if I sold it I'd have to buy another one somewhere else. I'm one of those tech workers, but I grew up here rather than transplant. People started fleeing California after they screwed that state up in the 80s and the flood never stopped. I like the area because it's home but I really don't understand the draw that keeps people pouring in from everywhere else. I'd be far happier if about 50% of the population moved elsewhere, I much preferred the quiet rural areas with grassy hills, farms and orchards. Oh well.

[manuel42]

I just started out with electronics and don't have much experience.
Out of curiosity i've bought a cheap Rigol DS1002 Z-E
I'm sure i can do everything i need with this oscilloscope but i've already replaced it with a (much more expensive) Keysight DSOX1202G.

My subjective reasons were:

• I found the rigol to be rather slow/unresponsive
• When changeing resolution, it often lost focus an i had to fiddle around to get the information back onto the screen
• I wanted a function generator
• Keysight did a good job with their adds and i like their brand

Again, nothing crucial, but i do like it way better now.

[wizard69]

Building a house right now is going to be a shock to the system.   lumber is 3X or more the cost it was a year ago.   I've been working on a few projects around the house, as money and time permit and was totally dismayed at the cost of a 2x4 and a sheet of OSB.   Absolutely disgusting!!!!!!

I've been saving money to buy a house, I'll dip into that fund to buy the extra test gear.  It's not like I'm going to buy a home anytime soon anyway, home prices are inflated so much now.

[wizard69]

In my estimation the price went up due to an opportunity to make more money.

You will not replace a well equipped scope with this unit but an AD2 can be extremely useful on a bench for somebody starting out in electronics.   As others have pointed out it offers a lot of capability.

If I was just starting out today a scope would not be high on my list.   This mainly due to getting by for a long time without.   There is a real need for many tools to get started and frankly if you can get a lot of functionality out of one product, an AD2, it can save a student a lot of money.   Which is why college students buy the unit.

I'm still of the opinion that you should buy a scope when you can put down on paper what specs you need.   That is you have increased your knowledge about electronic to the point that you understand where your interests are and what is required to help pursue those interests.   In afterwords don't rush into a purchase.   A scope can be a great tool to learn electronics so don't get me wrong there, but it isn't required to start out with the basics.

I don't think I'd replace a full oscilloscope with a PC scope, but is the AD2 adequate as a replacement for a dedicated function gen?  Has Dave done a video on the AD2 and if so was the video recent enough to give a proper impression of the AD2 as it currently exists?  If they've raised the price to $400 I'm assuming there must be some increased reliability or functionality in the product to justify the price rise, or is it higher because of parts scarcity, or maybe an early victim to the inflation creep that's coming?

[rstofer]

My house has become absurdly valuable which sounds great until you realize that my property taxes are correspondingly absurd and it's wealth only on paper, if I sold it I'd have to buy another one somewhere else.

That's one thing that California got right!  Prop 13 guarantees that the property tax is based on 1% the purchase price regardless of escalation plus a very few add-ons for specific purposes.

Of course, that leads to unequal taxation for equivalent properties but so be it.

https://www.sccassessor.org/index.php/faq/understanding-proposition-13

In Silicon Valley we used to joke about selling our tract house here and having to buy a McMansion in Oregon just to avoid taxes on the capital gains.  That's certainly changed!

Today, a run-of-the-mill house in Sunnyvale is around $2 million

https://sf.curbed.com/2018/3/2/17073100/silicon-valley-house-home-sunnyvale-record-price-crisis

The "greater fool" theory is at work here!

[Lowkus]

I'm not sure how California does it, but property taxes in Washington are not based on the house price so much as it is the value of your home relative to the other homes.  Hypothetical scenario, people in your county vote for some public project that will cost $200k per year, and lets say you have 200 homes in the county and they're all valued the same, each house has to pay $1000 in taxes each year (because $200k tax bill divided by 200 homes).  If all the houses are valued at a billion dollars, each house still only pays $1000 in taxes.  If all the houses are valued at $2.50, they each pay $1000 in taxes each year.  Let's say our fictional county has only two houses in the entire county, both valued at $9.95, each of those homes will have a $100k property tax, because the $200k annual tax needs to get paid and it's up to those two homes to produce the money that's needed.  Where things get imbalanced is when one home is worth $5 and the other home is worth $10, now the guy with the $5 home is paying 33% of the taxes due ($66,666) and the guy with the $10 home is paying 66% of the taxes ($133,333).  It's all an issue of the ratio of what your home is worth relative to other homes.  If your house goes up in value in the same proportion to all the other homes then your taxes really won't change much, it's only a problem when your home goes up in value while other homes don't go up.  Or, more likely, your taxes are going up because people in your area vote for a lot of stuff that costs money, then those expenses get put right onto your property taxes.

[Lowkus]

If I was just starting out today a scope would not be high on my list.   This mainly due to getting by for a long time without.   There is a real need for many tools to get started and frankly if you can get a lot of functionality out of one product, an AD2, it can save a student a lot of money.   Which is why college students buy the unit.

What kind of tools would you recommend someone purchase before an oscilloscope?

[Anthocyanina]

What kind of tools would you recommend someone purchase before an oscilloscope?

2 multimeters and a power supply should be super useful in helping you understand the basics of electronics and getting you started with building your own circuits

[rstofer]

I would think a couple of DMMs (probably 3) would be on hand before worrying about a scope.  If I were playing with a transistor common emitter amplifier, I would want to simultaneously measure Ib, Ic and Vce.  For low end DMMs, low voltage only,  I'm pretty fond of the Aneng 8008.  Dave has reviewed it.

I got along for decades without a proper power supply.  Batteries work well, wall warts are another possibility.  But, yes, a triple output power supply is handy.  If you want to play with op amps, sooner or later you will need a +15 -15 supply and then some other supply for the rest of the project.

Something like this might work well enough for op amp circuits:

https://www.jameco.com/z/PD-2515-MEAN-WELL-Power-Supply-Dual-Output-Open-Frame-15V-1A-Negative-15V-1A-24W_2100857.html

The power supply issue comes up about once a week.  Search...

I did have some high current 5V supplies because, back in the old days, all I worked with was TTL.  I didn't need analog circuitry, just 5V to feed the logic.

Watch w2aew's videos and see which power supplies he is using.  Most are ancient but affordable.  Here's one example of a dual output supply with analog meters.  You can always use one of your DMMs if you need more resolution for setting the voltage.

https://www.ebay.com/itm/402528610597

If I were trying to learn electronics (as opposed to cut-and-paste projects), I would be all over the AD2.  The problem is, folks look at the small package and decide it is a toy.  That's a really big mistake!

Anyway, 'power supply' threads are about as common as 'which scope' threads.  Search...

The most common 'want' specification is 0-30V 3A (two channels) and 5V 3A.  That's like a 200W space heater.  With today's use of CMOS, there is no justification for such a supply.  1A goes a long way and you can easily build a 3 output supply with 7805,7815 and 7915 linear regulators.  The regulators can also be used in circuits that are adjustable.

https://www.eleccircuit.com/dual-adjustable-power-supply-circuit-diagram/

[tunk]

And maybe a cheap component tester, something like an LCR-T4.
Edit: Dave has looked at it: https://youtu.be/7Br3L1B80ow

[bdunham7]

What kind of tools would you recommend someone purchase before an oscilloscope?

We'd need to know where you are at now and what you plan on doing in the near future.  The more specifics the better.  I started out planning on repairing and restoring old audio stuff and then found a source of used, broken test equipment and thought I could build up my equipment portfolio by repairing and selling test equipment and now I have a lot of stuff without any real expenditure.  I also finally acquired enough stuff to properly service radios, which is probably a larger list of stuff than you might think going in.

Fortunately I don't have to make a living at it--that is harder and probably less enjoyable.  What are you doing now?

[james_s]

I'm not sure how California does it, but property taxes in Washington are not based on the house price so much as it is the value of your home relative to the other homes.  Hypothetical scenario, people in your county vote for some public project that will cost $200k per year, and lets say you have 200 homes in the county and they're all valued the same, each house has to pay $1000 in taxes each year (because $200k tax bill divided by 200 homes).  If all the houses are valued at a billion dollars, each house still only pays $1000 in taxes.  If all the houses are valued at $2.50, they each pay $1000 in taxes each year.  Let's say our fictional county has only two houses in the entire county, both valued at $9.95, each of those homes will have a $100k property tax, because the $200k annual tax needs to get paid and it's up to those two homes to produce the money that's needed.  Where things get imbalanced is when one home is worth $5 and the other home is worth $10, now the guy with the $5 home is paying 33% of the taxes due ($66,666) and the guy with the $10 home is paying 66% of the taxes ($133,333).  It's all an issue of the ratio of what your home is worth relative to other homes.  If your house goes up in value in the same proportion to all the other homes then your taxes really won't change much, it's only a problem when your home goes up in value while other homes don't go up.  Or, more likely, your taxes are going up because people in your area vote for a lot of stuff that costs money, then those expenses get put right onto your property taxes.

I don't think that's true. My property taxes are based the tax assessed value of my house, which is typically below market value but still rises along with it. My house has not increased any faster than other houses in the general area but my property taxes have gone up by ~20% compared to last year, that's around $1200 a year out of my pocket and I don't have any more house than I had before. It is completely out of my control, the more people who flood into this area driving prices up the higher the direct cost to me. Expenses are rising a lot faster than income.

[rstofer]

Take a hypothetical Washington neighborhood (as described above) with 3 properties worth $10,000 and one property worth $1,000,000.  The 3 low end properties decide to vote for a massive project.  They pay essentially nothing for the project and the high dollar owner pays just about all of it.  Doesn't sound right fair to me!

Every election cycle, somebody takes a shot at overturning Prop 13.  It is the ONLY reason that people aren't taxed out of their homes.  In fact, old people being taxed out of their homes is the reason there was a ballot measure in the first place.  I'm old and I have no intention of living under a bridge.

Prop 15 was a losing attempt in the last election cycle to reassess the value of commercial property.  Fortunately, it failed.  Had it passed, it would be the first chip in the armor of Prop 13.  Sure, it purported to affect only commercial property but that could change fairly easy.  It may seem strange but politicians have been known to lie.

One limitation of Prop 13, the net property tax can only increase by a maximum of 2% per year and, typically, Social Security increases by a similar number.  A $1,000,000 property would be assessed a tax bill of $10,000 and it could only increase by $200 per year.  Approximately...

Of course, special projects can be approved by voters and will impact the tax bill.  Sometimes school projects or fire districts are funded this way.  It's not a big deal.  The 1% and 2% numbers are what keeps people in their homes.

[Lowkus]

I'm pretty sure my description of the tax situation is accurate, you can call up your local Department of Assessments and ask them how it works and they'll confirm.  Well, I did gloss over a state education tax that does do a straight percentage from your assessed value, but that particular tax is a small percentage of your property taxes.  Also you have to factor in what kind of business activity is going on around you, because businesses pay a personal property tax that goes into the same pool of money that residential homes are paying into, when the business go bust then more of the tax burden falls onto the residential home owners.  Also there's a senior citizen exemption to reduce taxes for low-income seniors, which is good for the seniors but the money they avoid paying then gets put onto everyone else in the levy district.

[Lowkus]

We'd need to know where you are at now and what you plan on doing in the near future.  The more specifics the better.

I've been doing computer programming for about 30 years (VB.Net unfortunately, which doesn't translate to electronics as well as C/C++/C#).  I've watched most of Dave's videos but my retention of the information is lackluster.  My first project goal is to build a rotary encoder knob that changes the value displayed on an LCD.  I expect most of my projects in the future will stay in the realm of digital audio generation, but I'd like to do some FFT processing for more advanced projects.

[rstofer]

There are many Arduino projects using rotary encoders and LCD displays.

https://www.seeedstudio.com/blog/2020/01/19/rotary-encoders-how-it-works-how-to-use-with-arduino

This approach let's you take advantage of your C skills.  Yes, the Arduino libraries are written in C++ but most of the user code will be written in C.

There are better ways to do the encoder logic.  My favorite is to get an interrupt on the level change on either pin in both directions (rising or falling).  Then I use a state table to track the transitions and increment/decrement the count.  This means I don't have to poll the encoder in the superloop - loop().  Obviously, if you just received a rising edge interrupt, you change the port around to look for a falling edge.  The state table is responsible for making sure you don't count contact bounces.

[bdunham7]

I've been doing computer programming for about 30 years (VB.Net unfortunately, which doesn't translate to electronics as well as C/C++/C#).  I've watched most of Dave's videos but my retention of the information is lackluster.  My first project goal is to build a rotary encoder knob that changes the value displayed on an LCD.  I expect most of my projects in the future will stay in the realm of digital audio generation, but I'd like to do some FFT processing for more advanced projects.

An Analog Discovery and a nice breadboard would probably be a way better fit for what you want to do at the moment. 

Once you've made your circuit work, you can learn how to make a circuit board in KiCad. 

Then you are 90% of the way to having a complete 'product'.

[Canis Dirus Leidy]

Speaking of digital logic. The price of Chinese clones of the eight-channel Saleae Logic on Aliexpress is about $10 (including delivery), and its capabilities are sufficient to view data exchange via low speed serial bus or PWM signal from microcontroller.

[Old Printer]

It’s unfortunate that the price of the Analog Discovery has moved past a Rigol 1054Z, that makes it a very tough sell. It is truly the Swiss Army Knife of electronic T&M equipment, but without a knob or screen it takes a beginner with a good imagination to get past the current price. I assume they are dependent on college professors mandating it for course  participation to maintain their sales. Glad I got mine when they were well under $300.

[rdl]

Years ago I saw a post on another board that Newark was selling a thing called "Analog Discovery" for $99 as an "Engineers Day" special. They said it was a great deal and recommended everybody grab one. Without even knowing what it was, I bought one. Really happy I did now. But I agree that the newer version seems a bit pricey.

[rstofer]

It’s unfortunate that the price of the Analog Discovery has moved past a Rigol 1054Z, that makes it a very tough sell. It is truly the Swiss Army Knife of electronic T&M equipment, but without a knob or screen it takes a beginner with a good imagination to get past the current price. I assume they are dependent on college professors mandating it for course  participation to maintain their sales. Glad I got mine when they were well under $300.

At my grandson's university, the labs are set up around the AD2.  You can provision for a lot of students when the educational price is about $100.  More important, in the time of Covid and no in-person labs, students are just about compelled to provision their own lab.  You really can't do EE courses without some amount of lab work.

Somehow, a plot of the function Vo = Vin * (1-e^-t/Tau) isn't as satisfying as actually seeing the waveform of the charge and discharge of a capacitor.  Sure, I know the output is about 63% at t = 1 Tau but I really believe it when I see it on a scope.  Not just an AD2 problem, any scope can display this result.  You just need an appropriate source of a square wave and perhaps even the compensation test point would be adequate.

[bdunham7]

It’s unfortunate that the price of the Analog Discovery has moved past a Rigol 1054Z, that makes it a very tough sell. It is truly the Swiss Army Knife of electronic T&M equipment, but without a knob or screen it takes a beginner with a good imagination to get past the current price. I assume they are dependent on college professors mandating it for course  participation to maintain their sales. Glad I got mine when they were well under $300.

I don't think there's much overlap between the AD and a Rigol scope.  The OP seems to be comfortable enough with computer controls and a regular scope would probably be more limiting.  The AD2 may no longer be a bargain, but it is probably a complete solution to the OPs needs, whereas with old-school instruments you need a scope, a power supply, a DMM, etc etc. 

[rstofer]

I'd like to do some FFT processing for more advanced projects.

Almost every modern DSO can do FFTs and so can the AD2.  In my view, the AD2 does it better. 

When people talk about the utility of 4 channel scopes, they are usually talking about digital systems.  They are using the scope as a logic analyzer with some amount of protocol decoding.  The AD2 has 16 digital inputs/outputs and can be used as a 16 channel LA.  Plus 2 channels of scope displaying either digital or analog.  Or, some or all of the digital channels can be used as output to produce either patterns or discrete signals.

I'm not sure you can get equivalent test equipment as inexpensive as the AD2 even at its new price.  If resolution matters, just try to find a scope with a 14 bit ADC at anywhere near the price of the AD2.  Same with the 14 bit waveform generator.  The recommended scopes (SDS1104X-E and DS1054Z) have 8 bit ADCs.  I can't convince myself that it matters because these old eyes can't separate the pixels on the screen anyway.  Nevertheless, 14 bit conversion is better than 8 bit.

There's no doubt that I am a huge fan of the AD2.  I would always recommend it for people trying to learn electronics.  There's a lot of capability in that little box.

Download the Waveforms software and mess around with the Demo device.  It's free!

https://store.digilentinc.com/digilent-waveforms/

[rstofer]

I don't think there's much overlap between the AD and a Rigol scope.  The OP seems to be comfortable enough with computer controls and a regular scope would probably be more limiting.  The AD2 may no longer be a bargain, but it is probably a complete solution to the OPs needs, whereas with old-school instruments you need a scope, a power supply, a DMM, etc etc.

And a competent arbitrary waveform generator.  It seems that an ordinary signal generator just won't do these days.  Even so, a decent signal generator is another cost and the AD2 has 2 channels of arbitrary waveform generator.

I have yet to use the 'arbitrary' bit on my AD2 or my Siglent SDG2082X.  It would be kind of cool to write up some Fortran code to produce values for some waveform.  Nostalgia...

The AD2 is actually a great choice in test equipment.  Unfortunately, many think of it as a 'toy'.