Hammond Mfg. Co. Ltd.

, Electronics Division

www.hammondmfg.com

125ESE
UNIVERSAL SINGLE ENDED TUBE OUTPUT TRANSFORMER

 Designed for general purpose or replacement use (not Hi-Fi), in single ended, tube output circuits.
 Frequency response: 100 Hz. - 15 Khz at full rated power (see graphs for detailed response).
 For full frequency response (20 Hz. to 20 Khz.) - see our 1627-1642 Series.
 For push-pull output use, see our 125 Series.
 Open style with minimum 12" long primary & secondary leads.
 All sizes use butt stacked cores (using 29M6 steel) with an air gap, to reduce D.C. core saturation.
 Primary impedance range from 2,500 to 10,000 Ohms.
 Secondary impedance range from 4 to 32 Ohms.

WHT
YEL

GRN

BLU ORG

BLK
BRN
 Hammond Mfg. Co. Ltd., Electronics Division

www.hammondmfg.com
ELECTRICAL SPECIFICATIONS**
Schematic and Hook Up Data
Characteristic Typical
Input Impedance 2500 - 10000  PRIMARY SECONDARY
Output Impedance 4/8/16/32 
Output Power 15 Watts BRN WHT 32  @ 10,000 PRI
Max. DC Bias 80 mA 16  @ 5,000 PRI
8  @ 2,500 PRI

Primary - DCR
Blue – Brown 103.0  YEL 16  @ 10,000 PRI
Secondary DCR 8  @ 5,000 PRI
Black – Orange 167 m 4  @ 2,500 PRI
10,000 
Black – Green 225 m
OR
Black – Yellow 297 m
5,000  GRN 8  @ 10,000 PRI
Black – White 412 m 4  @ 5,000 PRI
Inductance @ 1.0 kHz, 1.0 V OC OR
Primary – Blue – Brown 5.43 Hy 2,500 
Sec – Black – Orange 3.70 mH
Sec – Black – Green 8.20 mH ORG 4  @ 10,000 PRI
Sec – Black – Yellow 16.2 mH
Sec – Black – White 32.1 mH

Impedance @ 1.0 kHz, 1.0 V OC BLU BLK 0

Primary – Blue – Brown 33.8 K
Sec – Black – Orange 22.8 
Sec – Black – Green 49.5 
Sec – Black – Yellow 98.0  125ESE
Sec – Black – White 200.0  SINGLE ENDED AUDIO 15W 80mA DC
See graphs for specific PRI: 10,000; 5,000; 2,500 OHM
response, Typ. 1.0db from SEC: 4, 8, 16, 32 OHM
Frequency Response 100Hz to 15KHz DATE CODE MADE IN CANADA

Dielectric Strength 1500Vrms

Temperature Range -40 To 105C
Hammond Mfg. Co. Ltd., Electronics Division

www.hammondmfg.com
Hammond Mfg. Co. Ltd., Electronics Division

www.hammondmfg.com
 Hammond Mfg. Co. Ltd., Electronics Division

www.hammondmfg.com

PRIMARY SECONDARY
TYPICAL TEST CIRCUIT
R S/
2

RL OUT

R S/
2
Measurement instruments
Hp4192a impedance analyzer
Hp3456a DVM
Keithley 2002 DVM
D scope series iii audio analyzer
Wayne Kerr 3255B with a 3265B

* All graphs input level 20dbu.

** The results are typical and are subject to normal manufacturing and electrical tolerances.

This drawing and the information in it is the property of Hammond Manufacturing. It may not be reproduced, transmitted or used in any manner whatsoever without the written permissio n of
Hammond Manufacturing. Data subject to change without notice.