[BrendaAnnD]

Careful. In all of these type sets I've seen, the field coil isn't used as part of the filtering circuit. On the Halson chassis I recently worked on, the 25Z5 was split up, one half doing the half wave rectification for the radio, the other half going directly to the field coil, with the other field coil connection going to B-. You can do a simple test to determine whether this would be the case with your radio. Measure the field coil with an ohmmeter. If it reads 7kOhm or greater, it should be wired as noted above. If it reads 2kOhm or under, then it's in the filtering circuit.