Thanks. I've already downloaded Lucas chess and some engines rating under 2000
Where I can find free downloadable chess engines rating ELO 1600-1900

Here's a good list of engines: http://www.computerchess.org.uk/ccrl/4040/. Pick some from farther down the list.
For a more complete list including multiple versions of the same engine, see http://www.computerchess.org.uk/ccrl/4040/rating_list_all.html.

Here's a good list of engines: http://www.computerchess.org.uk/ccrl/4040/. Pick some from farther down the list.
For a more complete list including multiple versions of the same engine, see http://www.computerchess.org.uk/ccrl/4040/rating_list_all.html.
Yes. That is the site where I found some engines. There is something for everyone.

Again if one want a good opponent, at level let's say 1900, it's to me clearly a better choice to pick up a very good engine well known to have a nice technique for lowering it's level, than a lower level engine.
There are may advantages : if done correctly, the kind of mistake the program will make are much more "human". Then if you progress, you just need to add one point to opponent strength instead of downloading a other one. And if you need help like analyse etc, then you have a good ally with the same engine.

it's a very old thread but the answer can be useful so here is an idea :
Look for some torrent named " 1145 chess engine torrent "
As the name suggest there is a huge amount of engines, including Celes Morphy Enigma Storm and such. I haven't checked if all are free or allowed, but I'm almost sure it's 100 legal and clean (haven't seen any big commercial engine at first sight not certain if there is some malware but not according MSE anyhow and no way there are malware if all freeware I think).
It's a good idea to keep this torrent alive unfortunately it has not been named very cleverly but it's really a treasure of massive number of old and not-so-old engines.
Now we can find some free engine not that old but playing a normal level and more like a human than old engines with some newer engines having the option of limiting the strength, sometimes adding a personality and a favourite strategy and such, making them very human like. Maybe that is better than searching for oldies to decrease the strength.
I finally obtained a copy of the torrent file. There are a handful of older, commercial engines (let your conscience be your guide). I ran the unarchived files against several AV programs, and four executable files were flagged heavily as trojans. (Two associated with commercial engines, and two associated with freeware engines.) I don't know whether they're false-positives or not. If you like rolling the dice...

My suggestions:
1) Pick up Lucas Chess. It comes with a whole bunch of engines.
2) Pick up some of the older commercial engines from their site if not in Lucas Chess. For example Komodo 9 and earlier are available at their site for free.

Leela older versions play very human like. Lucas chess has a huge collection of chess engines, some with fixed elo

Here are some of the engines that come with Lucas Chess. (And you don't need to use them from Lucas Chess. You can use another GUI.)

And five hidden files in the torrent that I haven't yet found. Why there would be hidden files, idk...
Edit - I found the five hidden files. They don't seem to be dangerous, unless xml files can be harmful. (A text file in one of the Crafty folders, and four xml files in a couple of Mediocre folders.)
Thanks. I've already downloaded Lucas chess and some engines rating under 2000