I have recently acquired an old "radio" from a friend of mine. The data plate offers the following information: Radiola 20, Model AR-918, 550-1500 kilocycles. It has five tubes, four knobs, and two large "tuning" type controls on the front panel
There is also a DC voltage indicator that reads to five volts with three volts being marked as redline. Also, there is a four wire lead with battery clips.

Can anyone tell me where I can find additional information on this radio.

Thank You

Hi Steve

You are lucky to have the Radiola 20 with tubes and the plug in volt meter.

The schematic can be found on nostalgiaair. Go to the home page, click on Rider Vol #1, then click on RCA 1-17.

Norm

: I have recently acquired an old "radio" from a friend of mine. The data plate offers the following information: Radiola 20, Model AR-918, 550-1500 kilocycles. It has five tubes, four knobs, and two large "tuning" type controls on the front panel
: There is also a DC voltage indicator that reads to five volts with three volts being marked as redline. Also, there is a four wire lead with battery clips.

: Can anyone tell me where I can find additional information on this radio.

: Thank You

:I also recently purchased a Radiola 20, Model AR-918 and tried to find the schematic on nostalgiaair, but could find Radiola 18
and Radiola 21. Could someone direct to the Radiola 20? Possible the site changed since the original feedfack.
Thanks very much.
Ken

Hi Steve

: You are lucky to have the Radiola 20 with tubes and the plug in volt meter.

: The schematic can be found on nostalgiaair. Go to the home page, click on Rider Vol #1, then click on RCA 1-17.

: Norm

:
: : I have recently acquired an old "radio" from a friend of mine. The data plate offers the following information: Radiola 20, Model AR-918, 550-1500 kilocycles. It has five tubes, four knobs, and two large "tuning" type controls on the front panel
: : There is also a DC voltage indicator that reads to five volts with three volts being marked as redline. Also, there is a four wire lead with battery clips.

: : Can anyone tell me where I can find additional information on this radio.

: : Thank You

Hi Steve,
You're lucky to find such a fine old radio. This set uses type199 tubes. These were the first really low current consumption tubes designed to operate from dry cell batteries. They have a filament voltage of 3 volts (later increased to 3.3 volts for reliability) and are intended to operate from a 4 1/2 volt battery (3 cells) with a rheostat control (variable resistor) to reduce the voltage to 3 volts. The meter is provided to adjust this. As the batteries age and their voltage drops the rheostat can be adjusted to compensate so they can work down to one volt per cell. These tubes are fragile and expensive so it's important to ensure the correct batteries are connected to the right terminals, if the B battery is joined to the filament (A) terminals they will immediately burn out. Also when operating the set the voltage must be set correctly. Use maximum resistance to get lowest voltage and bring it up to the mark (3 volts). Since it's 75 years old I'd check the meter accuracy first. Connect two cells to supply 3 volts and measure the meter voltage with your accurate multimeter and check the set's voltmeter reads the same. Good luck with the restoration. Don Black.
: I have recently acquired an old "radio" from a friend of mine. The data plate offers the following information: Radiola 20, Model AR-918, 550-1500 kilocycles. It has five tubes, four knobs, and two large "tuning" type controls on the front panel
: There is also a DC voltage indicator that reads to five volts with three volts being marked as redline. Also, there is a four wire lead with battery clips.

: Can anyone tell me where I can find additional information on this radio.

: Thank You