Despite the limited involvement of Hitchcock in this film, I quite fancied seeing this for historical and cultural reasons. A great deal of it was annoying, overlong, and not at all funny but I found Teddy Brown on the xylophone entertaining, there was the odd sight of The Three Eddies - three black men in blackface (culture was awfully iffy for much of the 20th century) - performing two enjoyable routines, and I appreciated Cicely Courtneidge just for being Cicely Courtneidge.
The linking material with the efforts of Gordon Harker trying to get a decent TV reception was cutting edge stuff. Experimental broadcasts had only begun the year before and was only available for a handful of people in the south east of England. Personally, I'm surprised that anyone outside London and not very, very rich gave a hoot about the service.
Source: Network DVD