View Single Post
Old 17th Jan 2008, 6:05 pm   #14
mastermanx2001
Retired Dormant Member
 
Join Date: Jun 2007
Location: London, UK.
Posts: 366
Default Re: Quad 2 Valve power amp questions

Hi Ed, Thanks for the info, The Quad II already has a a 2A mains fuse, perhaps this could be reduced to nearer your recommendation of 1A. My pair of IIs still have the original Belling Lee fuses in (could be from the late 50s!) Looking at the circuit diag, fot the II, I see the HT centre tap to earth, but cannot see it on the transformer tag strip (see photo). I presume that it must be connected internally, so may not be easy to gert at. Any suggestions? Regards, Paul.

Quote:
Originally Posted by Ed_Dinning View Post
Hi Paul, fusing is usually in the centre tap lead of the HT winding as well as on the mains input side; this protects against most faults, say 1A for the mains and 150/250mA for the HT.
39C is not that hot. Typically the hot spot temp is allowed to 120C max.
If you really want to reduce it you could add an external heater transformer and disconnect the heater wires from the normal one.

Ed
mastermanx2001 is offline