A brewpal wonders whether it is possible to force carbonate beer with a soda syhpon. If so, what would be the parameters? If this is a silly question: I’ve never seen one of those thingies in my life. :
I dont know. But I recently got one of these. Works great. Especially for quick carbing small samples for a final taste test before packaging.
Should I interpret that as a no? 
But this requires a keg?
No, it goes on a soda bottle. I fill a 12oz bottle about 8oz, squeeze out the air, screw on the poppet lid, hit it with 30psi, shake and refrigerate. One I left over night, another I left about 3 hours. Both were carbonated enough to make head and give an idea of what it will be like finished. Its a great way to sample a beer in its intended state and really see if its ready or not.
I got one of these when they first came out many years ago and they’re great, work quite well with bog-standard plastic pop bottles of any size, and it offers some control over the level of carbonation to boot. Definitely much better than trying to use a siphon bottle.
I don’t use it regularly, but it has most definitely come in handy on many occasions.
And it works.
+1 to this. Theses are quick and easy to use and relatively inexpensive. I’ve seen some stainless steel ones out there (ohhhh, the next shiny object!), but these plastic ones work just fine for the money.
not a keg but it does require a co2 bottle and qd