[Amps] Filament life

[Gudguyham at aol.com]

In a message dated 7/15/2006 8:47:32 AM Eastern Daylight Time, r at somis.org  
writes:

Lou ==  The SB-220 uses a current-limiting type filament transformer  
that  allows no more than 60% of the 3-500Z's rated filament inrush   
current to flow, so step-starting the filament is unnecessary.    
However, the inrush current to the HV transformer is such that it   
will eventually erode the contacts of the ON/OFF switch, so a step-  
start is still useful.
end



Yes, I thought that filament transformer was designed that way, but if  
confronted with the question on a YES or NO basis, Would it be best to cycle the  
filaments or leave them on during a session on the air? BTW the Ameritron 
manual  states that the filament transformer is designed with "impedance" that  
essentially step starts the filament.  Lou