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Bench Setup

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What equipment do I need for a safe repair bench setup?

Hi memoryman, Welcome to the party. :tu:

You should get some really good advice when the techs finish work. ;)
Meantime here's a few of my Do Nots.

Number one rule is don't touch anything you can't outrun. :cheesy:
Don't work Alone.
Don't wear Jewelry
Don't work in bare feet
Don't use cheap low grade DMM's if you are working on high voltage gear
Don't assume something is off,, always check.

I work on a wooden bench.
I stand on a 20mm thick rubber mat

As to equipment just get the basics first,,
A good DMM and meantime build a light bulb limiter
they are cheap and simple to make and can save
a lot of heartache try to fault find.

Do I need an Isotap or Variac?

Do I need a bread knife and a grapefruit knife in my kitchen?    Only if I am cutting bread and grapefruit.

Those are great things for a complete shop to have, but it all depends on what you are doing.   Those tools will not be of any use if you are winding pickups or building speaker cabinets.

Iso transformers are a must for working on SMPS, but I rarely use one otherwise.   I find the variac mainly of use working on solid state stuff rather than tube stuff.   Neither will be much help building overdrive pedals.

I have got by for many years now without a Variac, but I couldn't survive without a good dummy load.  @Phatt has already mentioned a limiting lamp.  You can get by without one on valve/tube amps, but it is essential for working on solid-state amps (unless you enjoy repeatedly replacing brand new semiconductors).  While they overlap a Variac and a limiting lamp serve rather different needs.

A signal generator and test signal sources such as a cassette or MP3 player.  Doesn't have to be fancy or super low distortion but it should have at least a reasonably clean sine output and be able to cover the audio range, 10Hz to 10kHz.

At least one good multimeter rated for the highest voltage you expect to encounter.  Both analogue and digital meters have their strengths and weaknesses, so I have several of each.

An oscilloscope.  Again it doesn't have to be fancy but even the most basic CRO is better than no CRO at all.

Working on synths and guitars I have found a frequency counter very useful for precise tuning, and it also removes the need for a signal generator with an accurately calibrated dial.

A Megger or similar high voltage insulation tester and high range megohmmeter.

A neon screwdriver to detect high voltages has been a life saver when a "dead" mains circuit or "discharged" high voltage caps in valve/tube amps turned out not to be.

I also have an LCR bridge for testing capacitors and inductors.

Bench power supplies of voltage range and current capacity depending on your needs, what you get in to.  I have several, 5V, 12V, +/-15V, 6.3 and 12.6VAC, and switchable high voltage up to 400 volts.

A bench loudspeaker, or two if you work on stereos.

And hand tools, lots of them.  A good soldering iron and stand (I have several of different powers), and a solder sucker, the biggest you can find.  Screwdrivers of every type and size, ditto pliers, and in particular good sidecutters.  I also have several suture clamps that get a lot of use.  Lenses and magnifiers for the increasingly microscopic world inside electronic gear.  Lots of dusting brushes, a "dustbuster", and big vac.  A torque-limited power driver and multi-bit sets for when you have to take out or replace lots of screws (synths, speaker boxes, etc).  Adjustable spanners small, medium and large, and socket sets and drivers.  A range of clamps, spring and screw, from tiny to large.  A bench vyce or three of different sizes.  Hacksaw small and large (particularly for cutting new pot shafts to length, but you should have a specific dirty area for metalwork well away from the electronics bench and speakers).

Writing implements, pencils, pens, felt tip pens in colours and sizes.

A bench notebook, and these days a digital camera with good macro capability for "records shots".

A bench calculator or slide rule (which never has a flat battery).

Leads; screened signal leads that allow you to adapt any sort of connector to any other sort, unscreened speaker leads both long and short, clip leads for informal connections.

Power boards (with inbuilt overload protection) so you have somewhere to plug everything in, and an Earth Leakage Breaker if there isn't one on the main switchboard.  (and note that if you use an isolation transformer you defeat the operation of an ELB.)

And by no means least, good lights, both general and adjustable so you can really see what is going on.

A rubbish bin and storage boxes to keep stock components and hardware in order and easy to find.

I also have several computers, for office work such as job sheets and records keeping, design work such as circuit simulation, PCB layout, circuit drafting, internet access to find circuits and component datasheets (giving advice and asking for help), and an old clunker for experimental work in the workshop which would be no loss should I happen to accidentally apply 400 volts to one of its ports.

Thermocouple (contact) and non-contact thermometers, sundry weights and scales, micrometer, vernier calipers.

etc., (I'm sure others will chime in with what I've forgotten).


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