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What's in your "lab"?

R

RJohan

pfm Member
I got a "new" 'scope yesterday, a Tektronics 502 true dual beam from, I guess, the early 1960:s. It's in an ugly 1960:s american cars metallic sea blue color shade (I love it!). Probably costed as much as a car when new. Always wanted to have something from Tek. And an even older Philips tone generator (dirt brown). Booth working nicely, they made things the proper way in those days!

So now it is:
- Tek 502 dual beam scope.
- HP very old scope.
- Philips tone generator.
- B&K valve volt meter.

Some modern stuff like multimeter, PC:s with soundcards, to booring to talk about.

Never does anything with them, but that's another story...

JohanR
 
Hi Johan ??

I just bought a 'new' 1970 ish Tektronics 335 portable scope off Ebay for £59 (little beauty too), don't you just love the quality ??

Why not post some piccies here ??

Mike
:cool:
 
*lab being a grand name for a cold corner of my garage + the desk in the study ;)

Avo digital multimeter
Maplin LCR meter
Thermocouple amp for DMM
Portable function generator
Marconi TF2015 RF signal generator
Marconi TF2171 synchronizer
Marconi AM/FM modulation / deviation meter
Marconi high impedance voltmeter (with powered valve-based probe!)
Hitachi Oscilloscope
Bench PSU
Temp controlled soldering station
Phillips crystal-controlled IF reference oscillator
PC-based 24-bit FFT analyser
VHF / UHF RF power/VSWR meter
Oil-cooled RF dummy load

A good mixture of old and new, but I have to say I'd love to change some of it for more modern (read: smaller) kit, but that old Marconi stuff keeps going.

The modulation meter was even recently serviced and calibrated, despite it dating back to the early 70's I guess, pretty good support I'd say.

Andy.
 
Well, we have the usual suspects:

Fluke 75 Multimeter
Maplin LCR Meter
Kiksui 2020 Scope
Neutrik TT402 Audio Analyser
Farnell function generators (various)
Levell micro-volt meter
Ersa temp. controlled soldering station
2 very nasty computers
and of course my favorite piece of equipment.... the lump hammer.

Remember:

Anyone can hit it and some will even get it working again, but it takes skill and judgement to know exactly where to hit it, and just how hard. That's all it takes to be a true engineer :D
 
From Andrew:
Marconi TF2171 synchronizer
Click to expand...

I've a TF2015 but couldn't find a TF2171 anywhere. Ended up buiding a 'locker box' which does the same job however.
 
can u guys advise what equipment i need to set up my own "lab" to build things like audio power supplies, ampps, etc.

as they say, you only buy once, so buy the best...

grateful for any suggestions.

i already have a temp controlled soldering iron and a draper multimeter (which i dont really like).

enjoy

ken
 
The standard workhorse is the oscilloscope and sometimes you can get them on eBay or at radio rallies for around £30-40. Stay away from the valve monstrosities as they're none too reliable although they do warm up the shack in winter. 20MHz bandwidth should be the minimum and will cater for most jobs in audio.

A signal generator comes next and they can be had for as little as £15 - in fact an old Sugden with reverse RIAA output, cost me all of a tenner from a radio rally. NiCad batteries make a good substitute for a power supply if only needed for short periods although a regulator such as a 317 is easily drafted into a simple bench PSU.

Buy a decent digital multimeter but stay away from the autoranging models unless you're sure about the reading the display. Some years ago, I bought some Micronta bench meters from a local Tandy store when they were on offer. These have been brilliant and apart from blowing a current fuse now and again, no problems have been encountered. I've since added Flukes, Racals and all kinds of esoterica but still rely heavily on the Microntas. Get a decent temperature controlled soldering iron such as the ones sold by Rapid. For around forty squids, you'll have a decent tool capable of tackling most workshop jobs.

Hope you enjoy the results of your hard work.
 
I'd just like to add that a PC with a decent sound card can act as a decent signal generator and also an analyzer.

My workbench is...

Old Dell Celeron Laptop* with a shit sound card.

Crappy multimeter that never seems to have enough resolution.

Impedence measuring jig. Basically this takes the output from an amp and feeds it into the soundcard on one channel and through a power resistor into the the other channel. The device under test is connected between the input and earth. This means that the resistor and the device under test act as a divider.

Measure a sweep or noise and you get the frequency response of the device under test.

Home made microphone preamp with measuring microphone made from Panasonic omnidirectional capsule from digikey heatshrinked onto the end of a thin acrylic rod.
 
I'd just like to add that a PC with a decent sound card can act as a decent signal generator and also an analyzer
Click to expand...
I feel this is the future as it is with amateur radio. The test gear on sale today is mainly processing power but of course, we already have heaps of this in a PC so it's pointless duplicating the facility in every bit of gear or amateur radio kit we have. Better and cheaper, quite apart from saving space, to have one processor for everything. I haven't tried the software programmes that works with soundcards but many seem to get along with them quite well.

It may soon be time to flog off all this energy hungry kit in the shop and rationalise things down to one or two multi purpose units controlled by a PC, who knows..??
 
A hassle I've got is the PC with the decent sound card is in a different room to the power amps and my laptop PC with a Line level stereo input has an awful sound card. I'm toying with the idea of getting a new Soundblaster External Audigy as then I could use the faster laptop... (which has a better sound card, but no line in (why do laptop makers not provide one anymore?)

Andrew Weekes knows a lot more than me about PC measurement systems.
 
I'd serioulsy consider the extra for one of the M-audio external USB sound cards.

My experience with SB stuff is not good, they are relatively inexpensive, but the SBLive, for example, could only sample at 48kHz - any other rate went through a real-time (and non-integer) sample rate conversion and sounded awful, and produced erroneous measurements.

The upside was they were cheap, which meant that when I was too lazy to design a 'proper' interface, with input protection, the replacement of an SBLive at about £20 wasn't a big deal ;)

Sound cards don't like DC...

www.m-audio.com is the place to look, you won't regret it. The ony thing I'd like is a 192kHz sample rate, 96k is limiting as it limits my measurements to 48k max. The ability to produce 24-bit, 1 million point high-res FFT analyses with a relatively cheap PC, soundcard and some suitable software is a definite winner though!

Andy
 
Originally posted by Andrew L Weekes
www.m-audio.com is the place to look, you won't regret it. The ony thing I'd like is a 192kHz sample rate, 96k is limiting as it limits my measurements to 48k max. The ability to produce 24-bit, 1 million point high-res FFT analyses with a relatively cheap PC, soundcard and some suitable software is a definite winner though!
Click to expand...

Check out www.picotech.com

Mark
 
The pico stuff is pretty good, but you'll see the 24bit resolution stuff is low-speed and for high-speed acquisition they are limited to 16-bit resolution.

I also think you are restricted to their own software, which is advantageous for most, since it's free with the hardware.
 
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