so i am looking to compile some relatively decent hardware: soldering pencil, benchtop power supply, oscilloscope, and more if i have a need (i already have a nice multimeter)

anyone have any good recommendations, i dont need top of the line because right now that would just be throwing money away, but i do want something that is going is somewhat quality, if the difference is $50 bucks between crap and good stuff, that is worth it, if its $500 bucks what is an intermediate product?

i am looking at weller soldering stuff and some mastech items on ebay

i have no idea where to begin with the oscilloscope

what do you people use? pictures of snazzy setups?

11/3/2008 1:28:30 PM

1) get a job where they have a nice lab and
2) get enough seniority to not have questions asked for anything you do
3) and chum up the lab manager (somewhat optional)
4) profit...

a few more steps than normal... but Using the lab at work after hours is way more efficient than trying to get your own stuff... The Scopes worth buying are $500 at last check

I haven't found Analog Oscopes that are cheap to be much use.

Power supplies you pay for the transformer and ripple... so if you want to source enough to power audio amplifiers be prepared to pay for them... shipping will be $70 alone since they weigh 75lbs

Soldering irons you can get for cheap on ebay... if you want to really do neat stuff you need the dual station metcals.

Frequency generators are easy to come by cheap.



[Edited on November 3, 2008 at 1:48 PM. Reason : but I haven't looked into this stuff in at least 3 years]

11/3/2008 1:46:11 PM

Quote :

"but Using the lab at work after hours is way more efficient than trying to get your own stuff"

yeah, thats what i figured, but the labs in my department are more geared towards nuclear stuff and not ee stuff

11/3/2008 1:59:46 PM

Scope: I just bought a LeCroy WaveMaster A620A scope. 6GHz, 4x20GS/s, real-time waveshape analysis, etc.

Power supply: California Instruments iXII, 6kVA up to 400V (AC,DC, AC+DC). Variable voltage, frequency, and high crest factor capable. Has arbitrary waveform generation when hooked up to PC.

Soldering iron: some generic Weller temperature-controlled station

Multimeter: I use a Fluke 287. Anything that measures true-rms, frequency, etc.

11/3/2008 2:09:18 PM

You're kidding, right?

11/3/2008 4:23:14 PM

^^ Are you saying you just bought a $50,000 scope for personal use?

11/3/2008 5:17:24 PM

Oscilloscope: An old Tektronix 485 oscilliscope I got from dannydigtl

Multimeter: Radio Shack special

Power Supply: Home made

Soldering iron: Weller

For most of the things I hobby around with (low power analog), more expensive stuff would be nice, but it's not neccessary. I can't really justify the cost. I do have a short wishlist:

-A digital o-scope. Nothing too fancy, but I would like the ability to hold a waveform and save it. Tektronix has a couple of relatively inexpensive digital models that I've considered. They're also running a 15% trade-in special through the end of the month.

-Power supply. I would like something capable of handling larger loads.

A nice soldering station is worth spending a couple of extra bucks on.

11/3/2008 5:50:13 PM

yeah i saw those ones that were <$1000 bucks

11/3/2008 5:59:03 PM

gofigure is spot on


easier to get a job then buy a 10 ghz scope

11/3/2008 7:17:36 PM

fuckin' A, everything mentioned in this thread is overkill... depending on what you're planning to work on, a 10MHz scope is enough for power stuff (induction heating, pulse transformer drivers, etc)... if you're looking to get into high RF stuff, then you may want a nicer scope...

You can get by with a 150$ scope (mine is a dual trace 60MHz scope), 50$ multimeter (grabbed mine at Lowes), 150$ LC meter (should probably shop this online), a 10$/40W pen-style soldering iron for boards, and a 20$ 150W gun-style soldering iron for larger wires.

When you buy a used scope, MAKE DAMN SURE you test it before you even make an offer. If the scope has a test output use that, if not, stick the probe in a wall socket and look for 60Hz

For a power supply, you should shop eBay for an old Variac. I found my 0-280V 7.8kVA Variac for around 150$ shipped with a blown fuse, I suspect because the guy didn't realize that model had internal fusing... realistically you will not find a deal like that unless you buy broken and do your homework, but you should be able to find a 0-140V >=1.5kVA unit for around 50$ easy.

11/3/2008 7:44:22 PM

he didn't say anything implying home use. for all i know he is building a setup at work/school (or whatever he's doing, i think he told me he was in school still).

but no, the equipment i bought was for a lab i built at work.

11/3/2008 8:20:49 PM

nah

^ i am still at ga tech, but this is just for messing around at home

^^ thx for the advice

[Edited on November 3, 2008 at 8:25 PM. Reason : 

11/3/2008 8:23:01 PM

Quote :

"a 10MHz scope is enough for power stuff"

You wont see the majority of the leakage inductance ringing with a scope this slow. You might be ok if its an analog scope. Or you could just over spec the hell out of any fet switching a transformer winding.

I use an analog and digital scope at work. They are relatively slow but still not this slow.

11/5/2008 8:02:02 PM

well what would you suggest is a good rate?

11/5/2008 8:05:21 PM

i have no idea what you're trying to do.

i measure side projects at work.

11/5/2008 8:11:36 PM

Take nyquist of your switching supply and multiply by 10

11/5/2008 8:22:01 PM

i doubt his goal in personal projects is designing power supplies.

who would want to do that?

11/5/2008 8:34:28 PM

Quote :

"You wont see the majority of the leakage inductance ringing with a scope this slow. You might be ok if its an analog scope. Or you could just over spec the hell out of any fet switching a transformer winding."

10MHz might be a bit on the low side, but I would say very workable if it's an analog scope. To clarify, I wouldn't recommend a digital scope at the price point I mentioned under any circumstances, if you can even find a real digital scope at that price. With the analog scope you can easily get an idea of the peak inductive rise even if you can't count cycles in the ringdown.

On my 60MHz analog scope I have a little bit of trouble triggering the ringdown in resonant switching but with enough care in the triggering I've been able to get clean pictures of ringdown and parasitic oscillations at several MHz above resonance. I'd say anything much more than 60MHz is massive overkill for a student/hobbyist and the extra data you glean from even a 60MHz scope is probably not of that much value -- isolating the conditions under which parasitic oscillations occur are about the only time I've needed that extra resolution.

For reference, I generally play with resonantly switched circuits < 200KHz for driving induction heating coils, hand-wound ferrite transformers, and Tesla coils. Leakage inductance of the load isn't a concern so much as assumption. I think these guys are coming from more of a professional EE perspective, where my perspective is more one of "how much power can I run through this puppy before components start going ballistic".

PS. if you aren't aware of this, most manufacturers of passives are more than happy to sample to hobbyists and students. IC manufacturers are also pretty generous when it comes to students / hobbyists. Power transistors are the hardest to sample, but you can generally find someone to sample low-end (<100W) stuff from. I've sampled easily over $1000 in components by going directly to the manufacturer and asking for a few at a time as I needed them. As a general rule, you don't know until you ask. They don't really seem to care if you let 'em know what you're doing with it and it's clear that you're not just trying to resell it.

11/5/2008 9:35:53 PM