Toroidal Transformer for 3CX800A7 amplifiers 230V primary

  • 2 x 464V @ 640mA
  • 13.7V @ 5A
  • 12.2V @ 2A
  • Self resetting thermal trip
  • 160mm diameter x 90mm height
  • Weight 7.5Kg

Price excl VAT: £224.50
incl VAT: £269.40


Toroidal transformer designed for use with 3CX800A7 amplifiers. It is a direct replacement for the SIGA 4956 as fitted to Linear Amp UK Discovery amplifiers that use the 3CX800A7 triode.

The transformer supplies a dual secondary for HT at 464V/640mA per section and designed to then go through a voltage doubler/rectifier circuit to provide HT for the 3CX800.

Heater winding is 13.7V at 8A

Additional tap for control circuits 12.2V @ 2A

Primary voltage is 230V 50/60Hz

A self-resetting thermal trip is incorporated in the transformer wired in series with the primary. The trip operates at approximately 120C.

All voltages stated are ‘open circuit’ voltages.

The current ratings stated are maximum current ratings when used for SSB. The transformer can be used up to its maximum rating. For modes requiring continuous carrier (RTTY/FSK/ etc) then you should aim for about 50% duty cycle or derate accordingly.