JoeR
There are many detectors that classify as analog types - usually, they are much older models, but not always.
First, you can think of most of the older - pre-microcontroller - machines as being totally analog - at least anything that pre-dates the original White's Eagle (mid 1980s ??). There are far too many brands and models to name, but detectors like the early White's 6000 series, Garrett ADS series, early Tesoro's, etc. Actually, analog 'machines' include B.F.O.'s, TR's, early and even some current VLF motion detectors - because they use non-digital analog circuitry.
Then too, there are hybrid-type detectors that use a combination of both analog and digital circuitry, but have an analog ID meter. Most, but not all, digital designs have a microcontroller chip, use an LCD display and feature membrane (keypad) 'soft-touch' type switches as opposed to analog units which normally have 'real' switches and knobs.
As far as target ID goes ...analog units are considered to be the one's that have a needle-pointer type of target identification ID meter.
Joe