AIRMASTER | Playing w/ Distorted Audio | Loudspeaker Woes

All capacitors less the micas were replaced in addition to out of tolerance resistors. The 8uF AC dropper capacitor is tacked in at this point and a fuse will be added as well down the road. The radio is now playing, but the audio is distorted due to the loudspeaker that needs to be rebuilt.
----------------------------------------------------
A simple old school method and procedure to calculate the required capacitor value to drop the AC voltage across the Heater string on vintage radios or alike that can take the place of a resistive line-cord or ballast tube.

A capacitor does not generate heat like a power resistor, so this is a big advantage, but surge voltage needs to be mitigated as well.
----------------------------------------------------
Another vintage radio (mid 1930s) from the shed to the shop, an AIRMASTER (Trade Name) 5 Tube Radio w/ Ballast Tube. The BM49B Ballast Tube rated at 300 mA is missing, so I will most likely use an AC capacitor in series to drop the Heater string voltage. A closely matching schematic is for an Automatic 939 in Riders 11-3.

6A7 - Converter
6D6 - I.F. Amplifier
6Q7 - Detector
25L6 - Output
25Z5 - Rectifier
Missing Ballast - 49V @300 mA - BM49B

The playlist for the series:
   • AIRMASTER | 5 Tube Radio w/ Ballast Tube  

LC Test Circuit:
   • LC (Front-End) AM Broadcast Tester - One C...  

Thanks for watching and subscribing to my channel on vintage radio repair and other related circuits.

#restoreoldradios