22-06-2015, 04:13 PM
awkward to answer really from a safety point of view I would recommend an isolating TX even I f its only two back to back transformers say from old battery chargers.
Then again I worked an radios and tv sets for over 20 years with out one.
I only bought one when tv sets started to use full wave rectifiers so the chassis was always at half mains voltage .
on an AC only set most (not all ) will have a mains isolating transformer .
if you intend to use scopes ect you do really need one as the negative os the probe will be connected to earth.
Please remember that high DC volts can also give you a nasty shock.
Always try and work on a set plugged into the mains with one hand in your pocket.
and stand on say a rubber mat.
in other words just be careful check the chassis with a neon screw driver ,try Not to hold the chassis while taking voltage readings
So a nice thing to have (isolating TX ) but not essential .
Rob T
Then again I worked an radios and tv sets for over 20 years with out one.
I only bought one when tv sets started to use full wave rectifiers so the chassis was always at half mains voltage .
on an AC only set most (not all ) will have a mains isolating transformer .
if you intend to use scopes ect you do really need one as the negative os the probe will be connected to earth.
Please remember that high DC volts can also give you a nasty shock.
Always try and work on a set plugged into the mains with one hand in your pocket.
and stand on say a rubber mat.
in other words just be careful check the chassis with a neon screw driver ,try Not to hold the chassis while taking voltage readings
So a nice thing to have (isolating TX ) but not essential .
Rob T
if its made by hand it can be repaired by hand
