This is a vintage Marconi BD851 14" B&W broadcast monitor from around 1958, I won this monitor for a very cheap price on Ebay some months ago!!!:D This monitor was a general purpose monitor for TV studio control rooms outfitted with Marconi camera chains, most particularly the Marconi MKIII! Having a Marconi MKIII camera chain myself this monitor is ideal for use with it! I was told these monitors produce superb sharp B&W pictures!!! This monitor is in excellent shape cosmetically, looks good on the outside, on the inside it is almost clean as whistle without caked dust and dead insects which is totally awesome!!!:D
I powered it up with the variac and the valves lit up and the tube which was good start, however no form of display on the screen and I smelled something burning and noticed one of the capacitors was dripping brown liquid which I thought would be PCB oil. Turns out that faulty capacitor is an electrolyitc so I wonder if it is PCB oil or electrolyte substance of some form? So this monitor needs a restoration job starting with the replacement of all paper capacitors and faulty electrolytics, I will have to order a batch of replacement caps from Futurlec and get started! Hopefully that's all that's needed to get this monitor operational.
Anyways here below are pictures and a couple of videos of this monitor: