View Single Post
  #7 (permalink)  
Old June 19th 07, 02:44 AM posted to uk.rec.audio
Phil Allison
external usenet poster
 
Posts: 927
Default Mains Transformer for tubes - suppliers in UK


"Ian Bell Boy Idiot "

Just got an email from Maplin to say they are out of stock of their one
and
only type of mains transformer for tube supplies (250-0-259 @150mA and
6.3VAC secondaries).

Where else can I get something similar in the UK?



** For a one off project - use two AC transformes.

The first supplies the valve heaters while the second operates in reverse
from the output of the first to supply the HT voltage.

Eg:

Tranny 1 = 240 volts to 9 volts (then rectified and regulated to give 6.3
DC )

Tranny 2 = 12 volts to 240 volts ( rectified to give 250 volts DC
approx )

NOTE:

Tranny 2 needs to have a somewhat higher secondary voltage to avoid high
magnetising currents when operated in reverse.

( This does not apply to a toroidal transformer )



........ Phil