Central Electronics 600L 15m output coupler
The 15m coupler wasn't working correctly and wasn't potted like others (probably a replacement part), so I took it apart.
I don't see any damage to the wire insulation. The inductance of each part seems reasonable. I.e. no shorts. The bifilar winding has large spacing, so no short is expected there.
Still this coupler does not work. The yellow tubing used as spacer in the L2/L3 bifilar winding affects the capacitance between L2 and L3. Its characteristics might have changed.
I don't know whether that will be enought to this level of malfunction.
[A part of L4 winding shown here. 2 tunrs over the rest of L4 and 2 more turns over L2/L3]
[Another view of the outer L4 winding]
[With the outer L4 winding removed. The bifilar L2/L3 winding is shown with the yellow spacer. Both winding are brown. The yellow tubing is used as a spacer.]
[The SWR sensor]
[The SWR sensor. One of the diodes is visible here]