Thread: Murphy V410 TV
View Single Post
Old 6th Oct 2018, 10:44 pm   #18
FERNSEH
Dekatron
 
FERNSEH's Avatar
 
Join Date: Mar 2005
Location: Gateshead, Tyne and Wear, UK.
Posts: 7,444
Default Re: Murphy V410 TV

Just about all the waxie and Hunts capacitors needed replacement.

The attached picture shows the results achieved so far. There's that frame linearity fault to sort out and also a curious disturbance on the picture which takes the form of random horizontal lines. The latter is the result of line timebase pulses entering the IF amplifier and causing bursts of oscillation. The effect is most apparent when the contrast control is turned down to minimum.

The V410 has a "gated" vision AGC system. I'm certain that this not a back porch sampling system and is more likely to be a sync cancelling circuit.

DFWB.
Attached Thumbnails
Click image for larger version

Name:	MurphyV410_7.jpg
Views:	227
Size:	86.5 KB
ID:	170436  
FERNSEH is offline