5002K (600 : 600)

Balanced audio output transformer (Urei 1176 Rev A–E compatible)
 
The 5002K is a 600:600 Ω balanced output transformer, faithfully inspired by the original UA‑5002 used in Urei 1176 revisions A–E. Built with CRGO M6 laminations and bifilar winding, it delivers classic compression tone with a dedicated 20:1 tertiary feedback winding for negative feedback (NFB) in the output stage.
        
 
 
Model
5002K
Turns Ratio
1 : 1
Impedance Ratio
1 : 1
Nominal Impedance
600 Ω : 600 Ω
Primary DCR
54 Ω (bifilar)
Secondary DCR
54 Ω (bifilar)
Primary Inductance
~2.3 H @ 100 Hz
Core Material
CRGO M6 (grain-oriented silicon steel)
Core Format
EI‑57
Core Options
Gapped
Feedback Winding
~20:1 ratio, ~45 turns
Feedback DCR
1.52 Ω / 255 Ω
 
Frequency Response
 
Flat from 20 Hz to 20 kHz
Gapped version emphasizes saturation and character
Measured with 600 Ω source / 600 Ω load