Hmm, if it's actually been etched you might have to try polishing it with a glass polishing compound.

That said, if the glass is still in good shape and it's just stubborn dirt, I've had good luck with Bar Keeper's Friend.

Absolutely no idea, Tim, but it would be interesting to see a picture.

I recently bought a pair of GE Form 101FR Clamshell streetlights which were originally used on Wilshire Blvd. in Los Angles California.  The problem I have is that the glass refractor for both fixtures looks really cloudy and dull instead of transparent/clear and shiny . They almost looks like they've either been acid etched or media blasted . Has anyone ever seen this or know how to remove it  ?  Whatever it is it's not like the usual "fog" I see on glass refractors which is usually caused by smoke or off-gassing from the gaskets . 

 I have a 1942 copy of "Fluorescent Lighting Manual" By Charles L. Amick .  It's pretty neat and even has a bunch of info on the early RF fluorescent tubes and fixtures . 

Interesting, I've always wondered if there was some good reference material for something like this. I suppose the chokes would be simpler but stuff like MV and F40 ballasts would be harder to do in a combined design. Breaking it up to having a separate step up transformer and choke section (like on the early fluorescent ballasts) might be easier. 

I have a older IES lighting handbook from the late 70s which is quite fun to read though. I don't have them but I think the older books on HID lighting and fluorescent lighting are also pretty nice as well.

Has anyone else gotten into the habit of collecting lighting books for supplemental information? I recently got a few for Christmas, including some on efficient fixture design from the 80s and one from 1952 on fluorescent lighting. A few days ago I received a book on pre-electric mine lighting from one of the staff members at my college. I told him about my hobby and one of his relatives wrote the book and had a few extra copies sitting around and he generously gave one to me. That book is very detailed and about a thousand pages long! At some point tonight I need to catalog all the books I have on lighting...

I've been busy getting back to college so to preface I apologize for not replying sooner. I will say I have found some information in the form of a book I got for Christmas. It's simply called Fluorescent Lighting and was published by Philips in 1952. It goes over all aspects of the stuff, but important to this topic it has a chapter on ballasts. There's a few calculations on how to make a choke for an FL lamp, so over this summer I shall have to try designing and making one. I'll probably start off with a 120v choke for a F20T12 lamp as that's what easiest to test for me.

I've found the lamp out now, so will light it tomorrow and do some measurements. Heading to bed now, it's been a long day and we actually have to get up in the morning   to let the council sparky in to have a look at some work we need doing.

If the currents right then you are likely to be all good with that ballast as it won't run as hot as mine. Will be interested to hear what the lamp voltage is when you measure it.