sysop@hub:~/explainers/technician-toolkit-guide$

technician-toolkit-guide

Most hardware jobs fail on the way to the job: the wrong bit, no adapter, no way to test a cable. This is the kit that covers ninety-five percent of what a small company throws at you, with what each piece is for.

screwdrivers and bits

Six heads cover nearly everything in IT. A bit that is one size too small ruins the screw on the first try: when it wobbles, it is the wrong one.

Where	What you meet
Desktop PCs, servers, racks	Phillips PH2 for nearly everything. Cage nuts want a 10 mm socket or the little hook tool. Some server rails are Torx T15.
Notebooks	Phillips PH0 and PH1 on the bottom, PH00 inside. Business models increasingly Torx T5 and T8. One M.2 screw that is always missing.
Apple	Pentalobe P5 on the MacBook bottom, P2 on the iPhone, Torx T3 to T8 and tri-point inside.
Hard disks, game consoles, some printers	Torx T8 and T9, often the security version with a pin.
Wall mounts, monitor arms	Hex keys 3 to 5 mm, and M4 screws of the right length for the monitor: too long cracks the panel.

A bit set with a slim, long shaft reaches the deep holes of notebooks. Thick handles do not.
Magnetic tips are fine near modern electronics and save every dropped screw.
Press hard, turn slowly. A rounded-out screw head costs an hour.
Keep screws in order: an ice-cube tray, a magnetic mat, or stuck to a sheet of paper where you draw the outline of the device. Notebook screws differ in length, and a long one in a short hole goes through the board.
An electric precision screwdriver is a luxury that pays off from the tenth notebook on.

opening and holding

Plastic opening tools and picks: for clips on notebook covers and monitor bezels. Never a metal screwdriver: it leaves marks and slips into the battery.
Tweezers, angled and pointed: for ribbon cables, jumpers and the screw in the fan.
ESD wrist strap, clipped to bare metal of the case. Cheap, and the damage it prevents shows up weeks later as "random crashes".
A head torch. Under desks and in racks you need both hands.
Side cutters and flat-nose pliers, small. For cable ties and bent case tabs.
Compressed air or an electric blower, a soft brush, isopropyl alcohol (90 percent or more) and lint-free cloths.
Thermal paste, a small tube. Needed every time a cooler comes off.
Cable ties, hook-and-loop ties and a roll of labels. Hook-and-loop in racks: it comes off again without a knife.

a multimeter, and the three things to measure

Checking a notebook charger: red probe into the middle of the plug, black on the outside. The reading should be the voltage on the label, or a little above. Zero means the charger or its cable is dead.

Question	Setting	Good
Is this charger or power brick alive?	DC volts, 20 V or auto	The voltage on its label, within about 5 percent. USB-C chargers show 5 V until a device asks for more.
Is this CMOS or UPS battery flat?	DC volts	A CR2032 coin cell: 3.0 V new, replace below 2.8 V. A 12 V UPS battery: about 12.6 to 13 V rested, below 12 V it is done.
Is this cable or fuse broken?	Continuity (the beep)	A beep from end to end. No beep: broken.
Does the PC power supply deliver?	DC volts, on a plugged-in running system	Yellow 12 V, red 5 V, orange 3.3 V, each within 5 percent. Measure at a spare drive plug.

Never measure inside a power supply or on the mains side. The capacitors hold a charge that injures, long after unplugging. A PC power supply is replaced, not repaired.
A basic meter with automatic range is enough. Pay for good probes and a fuse on the current input, not for digits.
A cheap USB-C power meter shows what charger and cable really negotiate: the answer to "it charges slowly".

for the network

A cable tester with a remote end: shows broken or swapped pairs in ten seconds. The models for a few dozen euros test wiring, not speed.
A tone generator and probe: finds one cable in a bundle of forty, and the wall socket that nobody labelled.
A crimping tool and pass-through plugs, or better: a punch-down tool and keystone jacks. Hand-crimped plugs are the first suspect in every later fault.
A short patch cable you trust, marked. Swapping it in settles half of all "the port is dead" tickets.
A USB network adapter, 2.5 Gbit, with USB-A and USB-C. For notebooks without a port and for capturing next to a suspect device.
A USB to serial console cable (RJ45 and USB-C ends). The day a switch has lost its configuration is not the day to order one.
A small unmanaged switch and a travel router: to put your notebook between two devices, or to give a room network for an afternoon.
A PoE tester or a PoE injector: is the port dead, or the access point?

the USB sticks

Four labelled sticks save more time than any single tool. Write the date on the label: an installer from two years ago means two hours of updates.

One multi-boot stick (Ventoy) holds all installers and rescue systems as plain ISO files. Keep a second, classic one for the machines that refuse to boot it.
Rescue system: something with disk tools, ddrescue, a browser and a network stack. SystemRescue or a Linux live image.
The maker's diagnostics for the hardware you have most of.
Use fast sticks or a small SSD in a USB case. Installing from a slow stick doubles the time.
The driver stick is for the fresh installation that has no network driver and therefore cannot fetch one.

adapters and spares that pay for themselves

Have	Because
USB-C to HDMI and to DisplayPort, HDMI to DisplayPort both ways (active)	Meeting rooms. Every time.
A USB-C dock or hub you know	To test whether the user's dock is the problem.
A known-good power cable, a C13 and a cloverleaf C5	Cheapest fix there is.
A universal notebook charger, USB-C with 100 W, and a certified 100 W cable	Most notebooks since 2020 charge from it.
A SATA to USB adapter and an M.2 case for NVMe and SATA	To clone, to rescue data, to look at a drive from a dead machine.
CR2032 cells	Clock resets and settings lost after power-off, on PCs older than five years.
A cheap USB keyboard and mouse, cabled	Firmware menus and dead batteries.
One spare of whatever you have twenty of	Monitor, dock, charger, switch: a spare turns an outage into a swap.

what not to buy

Kits with 120 bits of which 100 are for nothing. Twenty good ones beat them.
Certifying cable testers for thousands, unless you sell cabling. Rent one for the day.
Soldering stations, unless you solder. Board-level repair is a trade of its own.
Driver updater and "PC tune-up" software, ever.
Canned air by the crate: an electric blower pays for itself in a month.

Prices and makes change, kinds of tools do not. Buy bits and pliers once, from a tool maker rather than from a gift set. Related: notebook hardware guide, desktop PC hardware guide, network hardware guide, connector identifier, storage upgrade planner, hardware buying guide, wizard: the PC does not start.