This is my postwar Philips B6X12A valve radio from 1962. The amplifier is designed in such a way you bi-amplify effect.Bi-amplify is just separating your high tones from your low tones and running them through their own separate amplifier.
- Country of origin: The Netherlands
- Build-year: 1961-1962
- Valves: 10 (ECC85, ECH81, EF89, EBF89, EAA91, ECC82, EL84, EZ81 and an EM80)
- Type: Super-Hetrodyne, IF-frequency 452/10.7KHz
- Wavelengths: Broadcast, HW, MW, LW and FM
- PSU: 110-245V AC 50/ 60Hz
- Speakers: 2x 800 Ohms (OTL)
- Chassis: wood
- Dimensions: 600mm x 289mm x 258mm
- Weight: 11.8Kg
You can find the schematic here.
Reason for the revision
The sound was very dull when I've first played the radio. After a while the sound stopped working as well.
So I saw the opportunity for doing a revision.
I've basically did some basic repairs, just replace the old capacitors and carbon resistors with new ones of equal value (or a little bit higher).
The new resistors are metalfilm type ranging from 1, 2 or 3 Watts of power dissipation.
There is also a 4 Watt resistor in use, you need to get creative in replacing this one, because it's taking all the "hits" from the rectifier valve.
I've combined 4 x 33 Ohms 10 Watts to give me 132 Ohm and 40 Watts.