A Necessity. Without a decent meter, you are virtually blind as far as fault finding is concerned. I reccommend an AVO 8 or similar, 20000 Ohms per Volt. capable of measuring up to 5KV AC or DC, 10 Amps AC or DC and resistance from 1 Ohm to about 200 MegOhms.
Highly Reccommended. The best kind incorporates a diode tester and an audible continuity checker. Some also include facilities for measuring capacitance and transistor gain, or Hfe.
A vital safety item. Don't leave home without it.
This should be very high on your list. A good clear display, frequency response up to 10 Mhz. At the very least able to resolve 5 Mhz clearly.
TEST PATTERN GENERATOR.
Virtually Essential. Should be capable of displaying cross hatch, grey scale and white raster. The ability to generate 405 and 625 Line signals on VHF/UHF is also a priority.
RF SIGNAL GENERATOR.
Very Important for RF/IF alignment. An accurate dial is important. Needs to be capable of generating IF signals for both standards. Also cabable of generating AM and FM signals.
It may come as a surprise to learn that I don't rate these terribly highly. It is often just as quick to try plugging in a replacement and some faults in a valve that would debilitate a TV set, such as microphony or intermittency, would not necessarily show up on a valve tester. The AVO one is better than the Mullard, but at the end of the day, substitution is always the best test. Have I saved you a few pounds....?
I Don't own one! In fact, I advise against sticking probes under final anode caps to measure EHT voltages. Many sets have other ways in which this can be measusred.
The following items do have their uses, but can mainly be considered luxuries, albeit one or two may be seen as time savers!! : Frequency Counters (Handy for Decoder work), Spectrum Analysers, RF Diode Probes, Wobulators, Sweep Generators. Some sets specify the use of a wobulator, but budget, size and price force me to put them in this section. If you feel that you need these items, by all means add them to your arsenal, but I have coped for over 15 years without!!