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Television Standards Converters, Modulators etc Standards converters, modulators anything else for providing signals to vintage televisions.

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Old 25th Jun 2005, 11:26 am   #1
oldeurope
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Exclamation dangerous modulators !

Hi,
I found this in the description of the LV20.

http://images.google.de/imgres?imgur...lr%3D%26sa%3DG

" I was half way through the restoration of this set, when I accidentally connected my VHF modulator to the live chassis and blew the modulator up. Doh! "


It is importand to make the areal output of the modulator
potential free and use an isulatet box for it.

This should be standard for a thing used with vintage equipment.
Look in my modulator thrads and the schematic how it can be
made. The caps are so called Y- caps. For your safety use only
this with an Y written on.

Kind regards
Darius

In the pics you can see the potential free coax RF output of
the London Birmingham modulator and the new modulator for the
Mark III standard converter
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Last edited by oldeurope; 25th Jun 2005 at 11:39 am.
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Old 25th Jun 2005, 12:08 pm   #2
Nickthedentist
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Default Re: dangerous modulators !

Or I suppose you could use one of those isolated aerial sockets salvaged from a typical 1980s TV which used a live-chassis design.
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Old 25th Jun 2005, 12:41 pm   #3
oldeurope
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Default Re: dangerous modulators !

Hi Nickthedentist,
they are female and you need a male.

Darius

In the pics you can see how it is made in the
Birmingham modulator. I swaped this one with Mike
for the PYE FV1.
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Old 25th Jun 2005, 7:40 pm   #4
Harry Wergs
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Default Re: dangerous modulators !

I suppose you could always make sure that the chassis is connected to mains neutral, and not mains line !!!
Harry
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Old 28th Jun 2005, 10:29 pm   #5
Danny
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Default Re: dangerous modulators !

hi all i have a distribution system so all my sets are ready to go when i want
to run them ( the ones ive restored that is) and i used old reclaimed isolators from colour sets. i fitted a coax plug and then plugged it into my dist amp.
then plugged the fly leads into them.
yes you should always make shure the mains is connected the right way round!.
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