Unbekannt Grundig Ausgangsübertrager (Ref. 9060-100.02)

Hallo!

Leider muss Ich weiter auf English weil meine Deutsch Sprachkenntnisse mir nicht reichen (obwohl Ich es gut verstehen kann; so können die eventuelle Antworten auf Deutsch sein!)... Meine entschuldigung!

I recently bought a pair of output transformers from the firma Grundig (probably from the sixties) which someone took out from an old radio whose reference he lost (so, no starting point to look for schematics). What I have is the transformer's reference - 9060-100.02 (no Google results to be found) and the measured characteristics (on the attached file).

I've used several old Grundig transformers in my amplifier projects but I never encountered one like this before. The turn ratio is abnormally low (around 1:4) unlike the usual 1:40 for EL84 single-ended output transformers.
The other puzzling fact is the existence of not one but two secondary coils, almost similar but independent and wound with double wire. The primary is of rather standard aspect and follows the usual colour code (blue-red-yellow).
As usual I applied some AC voltage to the primary coil and took the readings from the secondaries in order to calculate the turn ratio (N) and the impedance ratio (Z) but the results are far from 'standard' to me. Here are the calculations:

Apply 230VAC to primary (red-blue wires)
Read 61V from sec1 (black-green1 wires) and 64V from sec2 (brown-green2 wires)
Turn ratio for secondary 1 (black-green1 wires) N=230/61=3,8; Z1 = N2 = 3,9x3,9 = 14,2
Turn ratio for secondary 2 (brown-green2 wires) N=230/64=3,6; Z2 = N2 = 3,6x3,6 = 12,9



Any ideas of what this is all about? Am I thinking straight or am I missing something? Are these really output transformers or some sort of interstage ones? Any help would be greatly appreciated!
Thanks to all,
Renato