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Electronics => Beginners => Topic started by: Neshco on December 04, 2024, 06:54:25 pm

Title: Function Generator best buy for the noob
Post by: Neshco on December 04, 2024, 06:54:25 pm
Hi,
I would like to ask for advise for buying device appropriate for the beginner like I am.
I would like to buy some device that will be to some extent time-proof until I catch a bit more of electronic knowledge.

This is the web store (https://www.adroit.no/signalgeneratorer.html?product_list_order=price&product_list_limit=all) where I can get some discount and only those models there are in play.
I know that some of those are hackable, some have more options for less money etc, so if there is someone who mastered this topic and are willing to recommend to me something from the list, I would really appreciate it.
Thank you in  advance for any reply.
Title: Re: Function Generator best buy for the noob
Post by: Grandchuck on December 04, 2024, 07:04:00 pm
I like the Siglent mentioned in this thread (and other threads also):

https://www.eevblog.com/forum/testgear/siglent-sdg2082x-thd-measurements/ (https://www.eevblog.com/forum/testgear/siglent-sdg2082x-thd-measurements/)
Title: Re: Function Generator best buy for the noob
Post by: Neshco on December 04, 2024, 08:08:08 pm
Thank you, but you overestimated my needs and knowledge.  ;D I mean, I can pay for this beauty but would like rather to save some money for something else that I don't have.
What about 1032x and hack to 60? It is twice less money for it. What I lose comparing to 2082x except 20mhz?
Title: Re: Function Generator best buy for the noob
Post by: Doctorandus_P on December 04, 2024, 08:44:10 pm
There are a bunch of "chinese" function generators with two channels and at a price point of EUR80 to EUR150, mostly depending on the maximum output frequency.

They are not great, but they do have a lot of functions compared to their price. The main deficiencies are the power supply (low quality wall wart, but easily replaceable) and the DA converter(s), which are R-2R networks on FPGA outputs. This can be improved by replacing the resistors with hand sorted values, but this is finicky because the resistors are very small.
Title: Re: Function Generator best buy for the noob
Post by: Benta on December 04, 2024, 08:54:00 pm
A few years ago, I bought the FeelTech FY6600-60.
It has served me well until now and got good reviews.
Best bang for bucks IMO.
But I mostly work sub 1 MHz. 10 MHz tops.

Title: Re: Function Generator best buy for the noob
Post by: Grandchuck on December 04, 2024, 08:55:13 pm
Thank you, but you overestimated my needs and knowledge.  ;D I mean, I can pay for this beauty but would like rather to save some money for something else that I don't have.
What about 1032x and hack to 60? It is twice less money for it. What I lose comparing to 2082x except 20mhz?

I was going by your saying "that will be to some extent time-proof."

Yes, the 1032 is a good piece of equipment.
Title: Re: Function Generator best buy for the noob
Post by: Old Printer on December 05, 2024, 03:14:22 am
It would help knowing your budget range, but more importantly, what do you plan to use it for. Do you already have an oscilloscope? Some scopes are coming with a signal generator built in. I would rather have a discrete unit, but I started out with an Analog Discovery and it has served as a great learning tool given it's limitations.
Title: Re: Function Generator best buy for the noob
Post by: Aldo22 on December 05, 2024, 09:21:59 am
Define time-proof!  ;)

I think a €55 FY3224s (https://www.aliexpress.com/item/1005005756976271.html?) is a “best-buy” for a “noob”.
If you outgrow it, you haven't lost much money with this one. That is also somehow “future-proof”.
40MHz, 60MHz, 80MHz is not that important in my opinion if you don't know what for, but it costs money.
For higher frequencies, for example, a €40 TinySA with up to 350MHz and AM/FM is enough for me.

My first SG was this one (https://www.aliexpress.com/item/1005006099916070.html), which I soldered myself.
It's crap of course, but you learn something.  ;)
Title: Re: Function Generator best buy for the noob
Post by: Neshco on December 05, 2024, 11:00:18 am
Thank you all guys, my budget can be stretched but if there is no need for that I would rather by some more equipment. I had in my head like 300-400 bucks, more or less.
I already have Rigol DSO814, skipped the hack with the 804 and I regret now, but it is what it is and as far as I know the 814 doesnt have functoin generator.
For now, I plan to start in the audio field, but, who knows...
Time-proof mean couple of years while learning and experimenting, not that it would hurt me a lot if I later sell and loose few bucks on it.
Initially, in my head was Siglent 1032x and hack (because of the DSO814 "mistake") but still, decided to ask because maybe I am missing something obvious, that people with experience already know.
Title: Re: Function Generator best buy for the noob
Post by: paulca on December 05, 2024, 12:10:17 pm
I think it depends on your needs, accuracy and range.

If you are happy just "playing" and are not bothered by frequency range you could even just use your PC sound system as a function generator.  Upto 20kHz only of course.

Personally I bought a cheap chinese signal generator which does functions and arbs.  Though I have never really tested them in too much anger, I do use the signal gen part.  It's 2 channel and has been quite effective for my purposes.  Even things like generating a control voltage for a buck converter while bench testing a circuit.  You can then set the control voltage to a sine or saw and observe the buck output voltage on your OSC also matches.

I think it was $80 ..  "Feeltech".  FY6000 something.  Dual channel, 40Mhz, +/-20V (although not at 40Mhz).  There is a thread for it here in Test Equipment.  The largest down side of it is .... it has a non earth referenced switch mode power supply.  So it has micro-amps of 90-110V (in the UK) AC leakage current on it's outputs.  This isn't a big deal for 90% of things, but if you need to look at the 10% it's going to be useless.  There are guides on replacing the power supply with a linear one.  EDIT:  Those micro-amps of leakage current.  It should be considered, when you connect the signal gen to the input of an earthed osciliscope those "phantom 90-110V" will disappear.  However, you will be running a few microamps of AC current through the ground of the scope.  It's not going to break it, but it could upset some readings.  If you are trying to measure micro-amps of current with the setup it would be quite tricky to isolate out where the current is from.
Title: Re: Function Generator best buy for the noob
Post by: BILLPOD on December 05, 2024, 01:49:21 pm
Good Morning Beshco, I have the UT962E: https://uni-trendus.com/products/utg962e-60mhz-2ch-classic-series-arbitrary-waveform-generator
And I love the form factor....compact, and it also works as a Freq. counter. :popcorn:
Title: Re: Function Generator best buy for the noob
Post by: Doctorandus_P on December 05, 2024, 01:58:30 pm
Why are you having regrets? (about the Rigol scope?)

Even if you have a EUR 400 budget, the EUR 100 chinese function generators are still a very decent "universal" choice. I still recommend to buy such a thing, and then save up the rest of the money for later. You may develop special needs. Maybe a low distortion sine generator or a HF thing.

For around EUR 150 you can also buy a UNI-T or an Owon:

https://www.eleshop.nl/uni-t-utg932e-functiegenerator.html (https://www.eleshop.nl/uni-t-utg932e-functiegenerator.html)
https://www.eleshop.nl/owon-dge2035-functiegenerator.html (https://www.eleshop.nl/owon-dge2035-functiegenerator.html)

It may be worthwhile to spend more money on a function generator, but I'd say you'd need a good reason to do so. You can start with making a list of what you would expect of a function generator. You can also spend many days to review these things... Or just buy one for EUR150 and start using it. Chances are it's good enough for 10+ years. If it's not good enough, you can get some money back by selling it. For EUR 150 it's just not worth it to spend too much time on making a choice.

I have a JDS6600 myself. (Very similar to the Feeltech), and it's good enough for my purposes. But buying one with a "real" DAC instead of the R-2R gets you more linearity, especially when signal amplitudes get lower. The R-2R is the most limiting factor for my JDS6600.
Title: Re: Function Generator best buy for the noob
Post by: Aldo22 on December 05, 2024, 01:59:26 pm
Initially, in my head was Siglent 1032x

Somehow the thread title doesn't quite match your ideas.
When I think of “Best buy for the noob”, I don't actually think of a device costing 300-400 euros.
But OK, it's your money...  :)
Title: Re: Function Generator best buy for the noob
Post by: Old Printer on December 05, 2024, 02:28:19 pm
Unless you have a specific use case that you know one of the FeelTecs won't do, I would head in that direction. I got by with an Analog Discovery and an old analog $50 ebay sig gen for a long time. I watched the for sale area here and eventually got a good deal on a used, but very clean Siglent SDG2042X. Being in the middle of the EU you should get a decent offering of used equipment if you are not in a rush, so get something to eek by with and I think you will be surprised how far it will take you. Good luck in your journey.
Title: Re: Function Generator best buy for the noob
Post by: rstofer on December 05, 2024, 05:59:44 pm
Unless you have a specific use case that you know one of the FeelTecs won't do, I would head in that direction. I got by with an Analog Discovery and an old analog $50 ebay sig gen for a long time. I watched the for sale area here and eventually got a good deal on a used, but very clean Siglent SDG2042X. Being in the middle of the EU you should get a decent offering of used equipment if you are not in a rush, so get something to eek by with and I think you will be surprised how far it will take you. Good luck in your journey.
- emphasis added


Every time this topic comes up, I am driven to bring up the Analog Discovery.  In one small box you get a 2 channel scope, 2 channel arbitrary waveform generator, 16 bits of digital IO usable as a logic analyzer/protocol decoder and a 2 channel power supply (albeit limited voltage and current).

https://digilent.com/shop/products/mixed-signal-oscilloscopes/discovery-essentials/analog-discovery-3/

I would look at the "Pro Bundle" since it facilitates the use of 10x scope probes (I would buy FIXED 10x probes to protect the gadget).  You get just about everything you are likely to need while learning your way around electronics (which is why they went out of stock during Covid - university students were buying them up) and although I have other equipment I prefer the AD3 when I'm working through textbook problems and other simple projects.  I can spend a lot of time proving the equations we use for low pass filters actually show up on the display.

Download the software and play with the "Demo" device...

https://digilent.com/shop/out-of-the-box-solutions/

Siglent makes some excellent AWGs - I have the SDG2082 and it is terrific.
Title: Re: Function Generator best buy for the noob
Post by: Old Printer on December 05, 2024, 07:18:08 pm
Rstofer, I am with you as usual, which is why I asked if he already had a scope. Since it has become common to see a pretty good 4 channel, hack-able scope for $400 or less, and Digilent has gradually up the price to close to that on the AD, it has become a tough sell. Guys see 25MHz limit, it must be a toy or it will blow up my $3500 laptop... and write it off.A few years ago I bought a BeeLink micro computer with very reasonable specs for $275. It sits on a shelf under my bench. My 25" monitor is on an articulated wall bracket, out of the way, and I have a Bluetooth mouse and keyboard that live on a shelf also under the bench. That's like zero lost bench space and I have all the tools of the AD at hand. Tough to beat.
Title: Re: Function Generator best buy for the noob
Post by: Neshco on December 05, 2024, 10:39:32 pm
Thank you all for a plenty of useful and thorough advises. And how it usually come after it, it bring some more question and options.
I am really sorry if my question was, kind a confusing and contradictory, but it is exactly how I feel every time when need to make some decision of this kind.
As I already said, I have scope and cannot combine that way, but need to admit that Analog Discovery is kind of a amazing machine, especially logic analyzer, scope, and fg in one package. Didnt know that such a thing even exist.
Also, that little Uni-T guy, look really nice and price is on spot.
@Doctorandus_P
Yes, I have regrets because of the Rigol. Could get thorugh with the 804 hacked and save some money, but it is like it is. Not that much regret, just, it could be better and healthier for my wallet. But despite that, I love that scope.

Title: Re: Function Generator best buy for the noob
Post by: Terry Bites on December 07, 2024, 04:28:39 pm
The FY6600-60M 60MHz FeelTech is fantastic VFM.
Title: Re: Function Generator best buy for the noob
Post by: Neshco on December 09, 2024, 05:33:02 pm
Thank you all guys, after twisting here and there, finally decided to take Siglent SDG1032X. Overkill for me at the moment, but...
Thing that is really annoying is that it come without probes. Now need to wait some days to test while I order, and wait to come.
I did not expected this but...