Sowter Type 1125

10k:2.5k+2.5 Input Phase Splitter Transformer. Two identical outputs

Coloured Leads 1125-F
Size f style F
APPLICATION combines the functions of a bridging input transformer and a highly accurate phase splitter for use in recording studio amplifiers using balanced transistor or valve circuits. Ideal for push-pull power amplifiers. Can be driven from a balanced or unbalanced source from low to high impedance (0 to 10k0 ohms). Provides high common mode noise isolation and the high input impedance means the amplifier will present minimal loading to the source.  Identical to type 8920 but with reduced ratio. A secondary Zobel network is probably not required to adjust the resonance behaviour depending on the actual input capacitance of the driven stage. Secondary impedance 10k Ohms with windings in series and 2.5 k Ohms in parallel
FEATURES Mumetal core for minimal harmonic distortion and exceptional bandwidth. Balanced two chamber winding and 4 separate electrostatic screens for the ultimate in rejection of hum and other types of noise from ground loops etc. The two chamber winding also ensures the two secondary windings are identical in resistance, capacitance and coupling factor resulting in almost perfect phase split drive to balanced amplifier even at high frequencies. Multiple interleaved windings ensuring exceptionally good bandwidth. High bandwidth and very low phase shift even at 5 Hz ensures excellent transient response. Mumetal can for magnetic shielding. A relatively large core ensures high level capability.
RATIO 1 : 0.5 + 0.5
FREQUENCY RESPONSE 10k0 Ohm source 20k0 + 20k0 ohm load - 3 dB 5 Hz and 50 kHz
DISTORTION 40 ohm source 20K+20K load 0.05% at +20 dBu 50 Hz
MAXIMUM LEVEL 0.5 % THD at 50 Hz (40 ohm source) +28 dBu (19 V)
Phase shift unbalance at 50 kHz <1.0 degree
DC Resistance 784 Ohms (primary) 400 Ohms (each secondary)
Inductance 149 H
E A Sowter Ltd The Boatyard Cullingham Road
Tel:+44(0)1473 252794
Fax:+44(0)1473 236188