Just am RH Designs analyser/timer - But you'd have to pry it out of my cold, dead hands first
You are possibly wondering why?! It is true there is no substitute for test strips, but test strips take time to make and process, and for me anyway, time is a fairly precious resource. The analyser/timer from RHD (now sold through SDS) allows you to take readings from the projected image on the baseboard of highlight, shadow and anything in between, and it calculates and displays both the required exposure and contrast. You can adjust both to put particular parts of a negative on a particular shade of grey(zone). The analyser can be programmed and calibrated for up to 8 different paper types. so when you switch from e.g. multigrade IV to a fast paper like Kentmere everything is worked out. Calibration for each paper takes a little time, but you only do it once. These beasties are now £340 new. I would buy another tomorrow if mine failed. It gives me the ability to have a quick session in the darkroom because I can get very close first time with no test strips. Don't think, however, that they are a totally automated solution. My experience is that you still have to learn how to "use the machine", which takes a little time and practice. If you want to know more, read up on RHD website.
There IS no substitute for test strips for the ultimate fine-tuning, but an RHD analyser comes pretty close, if your pockets are deep enough.
I like the Besseler because it beeps every second during the exposure. That is a big, big advantage during printing while you are dodging or burning in. There are a few other timers that do the same thing and can probably be considered equivalent.
Thanks for the advice, Now sorted with a simple electronic timer thanks to this forum. So my enlarger Leitz Valloy II is is wired to a UK 3pin plug but no earth wire, I have a Kettle style three pin plug for the enlarger timer to connect to the enlarger. Th instructions for the timer show the enlarger being earthed into the plug that connects to the timer. There is no earth wire so do i need to earth another way or is it ok without?
If you have any concerns, use an RCD breaker between the wall socket and the timer.
Thanks. I thought I'd be ok as essentially it's just like a table lamp but the breaker is a good precaution.
For the earth-current breaker to work when there is a fault on the enlarger, you will need to have an earth on the metal chassis of the enlarger (assuming that the lamp-socket is in a metal head, which it is in the Valoy I think). If the earth wire only starts in the timer, then a short inside there could pop the switch, but the device doesn't give protection automagically with just a two-core cable to the enlarger. And you do have the correct size fuse in the plug of course, not 13A? ;)
[Bearing in mind that I'm not a professional electrical engineer, your safety is your responsibility etc. etc.]
EDIT: Maybe I misunderstood about the timer - if there is no earth wire out of the timer then how can one expect to trip the earth-current breaker at all???