Quest Q40 Target ID Chart: Reading the Scale on a Light Machine

A two-digit numeric target ID on a 0 to 99 conductivity scale, as specified in the Q40 manual. That is the same convention used by almost every modern machine with a screen, which means the ordering is familiar and notes from another 0 to 99 detector will broadly transfer.

Broadly, not exactly. Operating frequency, filtering and firmware all shift where a given target lands, so a quarter that reads 82 on a Fisher will not necessarily read 82 here. Treat carried-over notes as a rough map and rebuild them properly against your own machine in your own ground.

The definition worth keeping in mind is the same on every detector: the target ID is the machine's estimate of a target's electrical conductivity, expressed as a number. It is not an identification, and it is being estimated from a weak signal through several inches of dirt.

Bands rather than values, because a single number would misrepresent how any detector behaves in real soil.

Quest publishes a built-in rechargeable lithium battery rather than AA cells, and that is a real trade rather than a straightforward upgrade. On the good side, you never buy batteries, the weight is lower, and voltage stays steady through the session instead of sagging. Sagging cells change how a detector behaves before they stop it working, which is a genuinely annoying failure mode that sealed lithium avoids.

On the other side, you cannot swap a flat battery in the field. When it is done, the day is done, and there is no equivalent of dropping in a fresh set of Rechargeable AA NiMH Batteries, 8 pack cells the way you would on an Fisher F22 or an Fisher F75. A USB power bank in the pouch is the standard workaround and worth carrying from the start.

Wireless audio draws from that same battery. Quest includes low latency wireless Lite headphones in the box, which is a meaningful saving given that ordinary Bluetooth headphones are unusable for detecting: normal Bluetooth delay makes pinpointing by ear impossible, which is why detector brands build their own low latency protocols. Running them costs runtime, and the battery runtime calculator will tell you roughly how many hunts a charge gives you.

Coil choice changes a machine more than most settings do, and on a smaller brand the availability of third-party coils is not guaranteed.

Someone who values weight and convenience over brand support. The Q40 is light, the rods release quickly for transport, the battery is sealed and rechargeable, and the headphones are already in the box. For a detectorist who wants to grab a machine and go without assembling a kit first, that adds up.

The argument against is service and community. Fisher, Garrett, Minelab and Nokta have far more owners, which means more forum knowledge, more second-hand coils and easier repairs. If you like solving problems by searching for someone who has had the same one, a mainstream machine is the safer purchase. The Fisher F22, the Nokta Simplex Ultra and the Minelab Vanquish 340 all compete at or near this money with much larger user bases.

For the closest comparable machines, see the Teknetics G2+ chart and the Time Ranger Pro chart. The budget detector ID comparison lays out what each brand actually publishes about its scale, which is the most honest way to compare them. Kit lists sit under intermediate setups.