Up until now, I've always shot 4x5 transparencies, with acceptable results, simp ly because I don't have the space for a darkroom to do black and white. I recen tly started taking an introductory black and white class at a local art school. The class has taught me, among other things, an infinite number of new ways to ruin what would otherwise have been a perfectly good photograph. Despite the se tbacks I've suffered at my own hands, I'm hooked. Now I'd like to use a bathroo m in my house to set up a small darkroom. (So far I've only been developing and printing 35mm in the class.) I'm thinking of purchasing a used Omega C-700 enl arger for 35mm to keep costs down while I'm still getting my feet wet in black a nd white.

My question is this: Is it possible, or even desirable, to fit a cold light head in a 35mm enlarger? I've read the pros and cons of condensor vs. cold light he ads, and would like the flexibility of installing a cold light head later. Can this be done? Also, what is a jam nut?

Thanks for any insight you advanced b&w folks can provide me.