[Heatercathodeshort]

I started to sell the Marconi 20" 4800 in late 1969 just before the change to 625 UHF.
The early models had a few stock faults, tuner gang earthing strips and those nasty circular black electrolytics.

The last models I sold must have been around 1977 with the green printed panel. They were great receivers and regardless of fault could be repaired in less than 15 mins. You could even change the tube in less than 5 mins!

With a good tube the picture is excellent and well exceeds what the customer expected.

Customers hated the blacked out screen, correct of course with black level clamp. It gave the appearance of a breakdown and it took a long time to convince customers this was correct particularly with the fantastic RBM A640.

I will always have happy memories of the Thorn 1500, in fact of all the Thorn television chassis. [ OK except the 1600 and 4000] Only 2 difficult chassis in over 30 years production of millions of units. John.