I spent 3 years researching DIY silver generators. I wound up buying the SilverPuppy. It runs on almost any power source, from house power, solar or batteries (car to 9 volt dry cells). They have a SilverGen over at the chateau which is also a very good unit, but the Puppy has a few more options, like automatic cycling current swap from AC to DC. This eliminates oxide build up on the electrodes which makes for a nasty looking batch that must be filtered. The Puppy also has a magnetic stir feature.
_http://silverpuppy.com/
Do not be suckered in with particle size, in regard to home made CS. It will all be ionic and this is always very small particle, unless you overcook it and the particles agglomerate. You will know this by the color it takes on... from a light yellow to a darker yellow reddish if you really overdo it. The Puppy has an auto cut off which stops the process at consistently about 12 ppm. It is crystal clear and never overdone.
Here is a pic of my Puppy in action. It will make up to 1 gallon batches at a time, but it is really slow in that volume. I make 1 liter at a time. I am very happy with this piece of equipment, and the fellow who makes them has very good customer service.