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Old 09-25-2009, 06:51 AM
rollei35guy rollei35guy is offline
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Join Date: May 2008
Posts: 86
Quote:
Originally Posted by radio nut View Post
I used my digital meter and it does not show ac from the plus or ground of the cap to chassis ground or with my test leads on the plus and ground of it.
Looking at the schematic I believe this set has a 'floating ground'. That is the ground is not on the chassis but at several points that are tied together. Sometimes a solder lug or a tube socket lug, or a combination. There is usually a capacitor and/or high value resistor to chassis to bypass ac line noise. One side of the secondary of the speaker transformer runs to chassis ground too.

These are a bit safer than the notorious hot chassis models. Of course if that capacitor to chassis shorts then all bets are off. There are special caps for that purpose.

Look at the chassis and try to find where the points for this floating ground are.

Are you using an isolation transformer? Recommended regardless of the set.
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