I can't remember where I got this set, probably in the 1980s, but it was the closest I came to a 'project'.
The radio worked, and I could hear the sound of TV channels. As far as I recall, it had symptoms of a failed frame output transformer.
In the service manual I see a frame output
choke (S57 on a diagram, replacement part MK.511.88) but not a frame output
transformer. Does that make sense? Or am I missing something?
Long ago I kidded myself that the 520A was a rare and valuable secondhand set, because it was originally more than twice as costly as the relatively commonplace Bush TV22. I'm almost certain that the 520A was priced at 112 or 115 guineas.
Back to reality
it's not valuable, one was
auctioned for £48 in 2009.
Mullard equivalent
At
http://www.thevalvepage.com/tvmanu/mullard/mullard.htm I see –
Quote:
…MTS501 is a repackaged Philips 520A and the MTS684 the Philips 683U. They even cost the same…
|
– but there, the (1950/1951) price of the MTS501 is £79-16-0, and this
Jonz Valve Page photograph of a (pre-October 1949) MTS5
21 (£102-18-0) –
– appears to be an almost perfect match for my 5
20A:
The fabrics that cover the loudspeaker grille may be different. And if you wonder how the fabric of mine became so tattered, it's thanks to cats. In the first photograph above there's Pickle, emerging from a brief expedition into the shockingly dusty interior.
More on the Mullard MTS 521/521A:
Postscript:
http://www.thevalvepage.com/tvmanu/philips/philips.htm confirms that the 520A was also released as the Mullard MTS521.
Distinction
1934/1945 Philips 520A
radio pictured at
http://www.jllacer.com/Euro_Radios/philips520A.htm