05-15-2014, 11:13 AM
(I do not know where to find data on 2848 xfmr).
Well, just find the ends of your primary.
A Pushpull for 2x45 impedance is about the same as 1x47.
If it was a pushpull transformer, the ends of it were probably connected to the anodes, use those.
Here what you could do to make sure:
1. Unsolder the voice coil.
2. Using a Variac and a Voltmeter, supply a goodly amount of AC voltage to the full primary (to P-P ends). Say, 60V. Measure the output by the Voltmeter out of the secondary. It should be close to 0.6V.
3. If not, find a tap and an end of the primary that will give you 97:1 ratio, that is 60V fed to primary gives you about 0.6V output. These are your contacts to use.
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Another alternative: at some point you will need a Push-Pull xfmr, so save this one and get an SE transformer with 97:1 ratio. (well, it is 100:1 in Philco 20).
Well, just find the ends of your primary.
A Pushpull for 2x45 impedance is about the same as 1x47.
If it was a pushpull transformer, the ends of it were probably connected to the anodes, use those.
Here what you could do to make sure:
1. Unsolder the voice coil.
2. Using a Variac and a Voltmeter, supply a goodly amount of AC voltage to the full primary (to P-P ends). Say, 60V. Measure the output by the Voltmeter out of the secondary. It should be close to 0.6V.
3. If not, find a tap and an end of the primary that will give you 97:1 ratio, that is 60V fed to primary gives you about 0.6V output. These are your contacts to use.
-----------
Another alternative: at some point you will need a Push-Pull xfmr, so save this one and get an SE transformer with 97:1 ratio. (well, it is 100:1 in Philco 20).
