1500$ Budget ,I need your eperience  - Page 1
Forum section: electronics / testgear

author: eevblogfan
author_rank: Frequent Contributor
timestamp: June 17, 2013, 06:01:00 pm
content: heyI want to learn more into the linear part of things - But integrate the Digital world as wellso far I am stuck with DC electronic load , due to the neglegible time I had to work on that project plus budget limits ,I'd like to ear from you what sort of project you can offer me to do , In order to cover the biggest range of experience , be sure I'll have fun from any projectI thought of building from scratch linear power supply , but having some hard to get specs , such as 100uV load regulation ( range lower then 100mA )recovery time >10uS ( is it possible ? )please don't dear to yell at me for the rubbish I wrote above , that said without even think of any limitations , reallythe instrument I have (so far)Fluke PM2813E3610A2X HP3478AHP34401AAgilent DSOX2002Old(ish) Kenwood 40Mhz scopefluke 87Vfluke 287HP3366BHakko-fx888 ( I don't like the small thermal capacity , it's integral part of me ) may I jump up to ersa some day ? , well I hope to open thread about that .and I have got for now IET "High power" resistance box , 7 Decades . 1Ohm to 10Mohm , 0.1% , it's in my lab for repair , I might buy it for cheap .I am pretty sure the only instrument I miss is good electronic load ( to cover my stupide non stopping mistakes )no need for super high power , 10W 0~1mA should do , I already got 0.1% 100OHm resistors , I'll do something soon ( 0~1mA is good for any logics , perhaps another range for 10mA and above )and of course the fastest respon?e I can achieve , the better ( I think )with 1500$ , what is the most important things to have ?and please add links to ebay actions or products you'll be reffering to , and don't forget pricethings to buy :capacitors assortment ( I cant find where from)comperhensive resistance assortment , I think of getting 1/4W and perhaps jump to 1/2W or 1W . E12 should do right ?cabinets , lots of themmaybe few accessories , no more then 100$ ( grabbers . BNC stuff , etc ... )few soldering boards .. different sizesand I can't think clearly at that moment , please help me herethank youYuval

author: c4757p
author_rank: Super Contributor
timestamp: June 17, 2013, 06:12:28 pm
content: Quote from: eevblogfan on June 17, 2013, 06:01:00 pmSounds like you've got an idea right there! What do you need ours for?Yes, those specs are possible, though tricky. (I'm going to assume you meant recovery time < 10us).S = siemens. s = second.

author: eevblogfan
author_rank: Frequent Contributor
timestamp: June 17, 2013, 06:23:30 pm
content: Hey c4757pspecs should serve some purpose right ? well the only spec I can use here is that >10us recovery , >100uV load regulation is good for low power high accuracy stuff , but I plan on getting Fluke 5100A for cheapie , so I assume he will fit thaht need . although , the meaning of these specs from beginning was to challenge me , hence I am open to that ideaas for reference , I have got some 5V 20ppm/C onese , But I might dear using Lm399'sapart from nice power supply , is there any other Idea ? and please feel free to give me hard onesthank youYuval

author: eevblogfan
author_rank: Frequent Contributor
timestamp: June 17, 2013, 07:29:20 pm
content: heyhttp://www.ebay.com/itm/Agilent-MSO6012A-Mixed-Signal-Oscilloscope-8ML-/190806934357?pt=BI_Oscilloscopes&hash=item2c6cfac355out of curiosity , is that scope worth trading my DSOX2002 for ?tell you the truth , no need for any logic analyzer yet , as for BW , the bigger the betterthank youYuval

author: Zad
author_rank: Super Contributor
timestamp: June 17, 2013, 07:42:46 pm
content: Do you want to learn about electronics, or collect test gear?

author: eevblogfan
author_rank: Frequent Contributor
timestamp: June 17, 2013, 07:47:10 pm
content: since I have already the DSO , trading gear is fine , if added money was including , well I suspect my answer was 90% learn and 10% collect

author: smashedProton
author_rank: Frequent Contributor
timestamp: June 17, 2013, 08:11:28 pm
content: You may want to do what I did. Go to electronic goldmine and buy every assortment they have. Go and get some cheap plastic tool bins. Get a giant ass breadboard. Make sure you have plenty of all the jellybean components. That means a ton of 7400 logic. At this point in your career, more ttl less vhdl. The psu idea sounds great. Just to add to the fun, I will add a digital interface programmed with a soldering

author: smashedProton
author_rank: Frequent Contributor
timestamp: June 17, 2013, 08:12:58 pm
content: Right now my fun gen is a guitar..

author: eevblogfan
author_rank: Frequent Contributor
timestamp: June 17, 2013, 08:19:45 pm
content: hey smashedProtonQuoteI am really sorry if I got you wrong , Did you talked sarcastic?Digital interface to that ? , nope , I already got 2 proggramable supplies and besides that fact , I really like old linear touch , 10 Turn pots are fare more superior in my mind , almost any cheap/not tide ass costy . Digital interface is bad to my thinkingyou are absolutly right after I'll build the linear supply , That will gonna be nice challenge to fit that Digital control firstly , and attempting to cause it to feel as good as I can to my feel ( for example , that encoders , with two ranges , and speed detect stuff , allows 1mV resolution and some course steps with either speeding up or pressing the knob )

author: smashedProton
author_rank: Frequent Contributor
timestamp: June 17, 2013, 08:25:14 pm
content: I agree that digital interfaces are a bit fiddly. I meant a diy digital ammeter and voltmeter for the supply. The control would still be analog.

author: Smokey
author_rank: Super Contributor
timestamp: June 17, 2013, 09:50:18 pm
content: Build a mostly discrete audio power amplifier. That's a full analog smack to the face, but you can build it up one block at a time as you learn what all the sub-circuits do. You get a bit of everything in the design, including a really cool system you can show off to all your friends at the end (assuming you get it working). And you don't need to spend 1500 bucks to do it since you have a ton of gear already.Check out:http://www.amazon.com/Designing-Audio-Power-Amplifiers-Cordell/dp/007164024X/ref=sr_1_1?s=books&ie=UTF8&qid=1371505403&sr=1-1&keywords=audio+power+amplifiersandhttp://www.amazon.com/High-Power-Audio-Amplifier-Construction-Manual/dp/0071341196/ref=sr_1_3?s=books&ie=UTF8&qid=1371505403&sr=1-3&keywords=audio+power+amplifiersBoth books have a good mix of theory and actual circuits with the second, Slone's book, having more actual working schematics for various amps. It even has the PCB layouts if you want to cheat and use one of his designs.

author: eevblogfan
author_rank: Frequent Contributor
timestamp: June 18, 2013, 04:47:04 pm
content: Hey thanksI might start to love Audio , but at the moment I am looking for control loops and stuff to that content

author: Paul Price
author_rank: Super Contributor
timestamp: June 18, 2013, 06:33:16 pm
content: If you want to fine a nice project to work one consider this:Necessity if the Mother of Invention.Search your imagination to decide on some simple or even complex device that might seem to help you learn about something your are interested in, or something that is very interesting or very fun and playful or even something that might do something that is practical and innovative or just a little helpful to you or others.

author: madshaman
author_rank: Frequent Contributor
timestamp: June 18, 2013, 08:15:41 pm
content: I second that you choose something you have a need for.Barring that, the linear supply is a *great* idea, you'll learn the basics of a control loop plus all the fiddly bits and your 40Mhz scope should catch any oscillations if you choose slower (for DC applications) opamps and power devices.Something more ambitious would be a switch-mode AC-DC supply or DC-DC converter that operates in the tens of kilohertz maybe? Based around a cuk converter so you can dial in any voltage you like?I'd actually shy away from an audio amplifier, even a simple class A. Opinions may very but audio amps are fairly involved (well, like power conversion isn't), that's my two cents.