Is there a tube that can be substituited for a type 26 triode used in a Model 18 Radiola?

I have looked in the tube substituitions but did not see any listed.

Steve

There are no tubes as a direct substitute for #26. The 26 was made with a high current, low voltage filament so it doesn't allow hum in AC radios. This heavy filament is slow to heat & cool so it doesn't respond to the 60 cycle AC.

If you have a bad 26, resolder the two large filament pins. Any resistance here and the tube will not operate. If a 26 was plugged into a 71A socket it's all over.

Here are a couple things you could try. If you are missing one #26, leave the socket on the far left open. Connect your antenna to the second RF stage. The radio will still operate.

You might try #30 tubes in the RF stages. They were made for DC and have a 2 volt filament but in some cases will operate.. There will be hum if used in an audio stage.

These are temporary ideas to test a radio. Watch for 26 tubes at swap meets and flea markets.

Norm

: Is there a tube that can be substituited for a type 26 triode used in a Model 18 Radiola?

: I have looked in the tube substituitions but did not see any listed.

: Steve

: There are no tubes as a direct substitute for #26. The 26 was made with a high current, low voltage filament so it doesn't allow hum in AC radios. This heavy filament is slow to heat & cool so it doesn't respond to the 60 cycle AC.

: If you have a bad 26, resolder the two large filament pins. Any resistance here and the tube will not operate. If a 26 was plugged into a 71A socket it's all over.

: Here are a couple things you could try. If you are missing one #26, leave the socket on the far left open. Connect your antenna to the second RF stage. The radio will still operate.

: You might try #30 tubes in the RF stages. They were made for DC and have a 2 volt filament but in some cases will operate.. There will be hum if used in an audio stage.

: These are temporary ideas to test a radio. Watch for 26 tubes at swap meets and flea markets.

: Norm

:

:

: : Is there a tube that can be substituited for a type 26 triode used in a Model 18 Radiola?

: : I have looked in the tube substituitions but did not see any listed.

I will try that.

To resolder the filament pins, what would be the best way to remove the base?

Thanks

Steve

Steve

Just reheat the pins and reflow solder with your soldering iron. You don't need to remove the base.. The wires from the filament to pins sometimes oxidizes. When this happens the tube will have a high resistance connection and not light. It is a big problem with 26's as they operate on high current and low voltage filament.

Norm

: : Steve

: : There are no tubes as a direct substitute for #26. The 26 was made with a high current, low voltage filament so it doesn't allow hum in AC radios. This heavy filament is slow to heat & cool so it doesn't respond to the 60 cycle AC.

: : If you have a bad 26, resolder the two large filament pins. Any resistance here and the tube will not operate. If a 26 was plugged into a 71A socket it's all over.

: : Here are a couple things you could try. If you are missing one #26, leave the socket on the far left open. Connect your antenna to the second RF stage. The radio will still operate.

: : You might try #30 tubes in the RF stages. They were made for DC and have a 2 volt filament but in some cases will operate.. There will be hum if used in an audio stage.

: : These are temporary ideas to test a radio. Watch for 26 tubes at swap meets and flea markets.

: : Norm

: :

: :

: : : Is there a tube that can be substituited for a type 26 triode used in a Model 18 Radiola?

: : : I have looked in the tube substituitions but did not see any listed.

: I will try that.

: To resolder the filament pins, what would be the best way to remove the base?

: Thanks

: Steve

Steve,

Check EBAY for RCA Radiotron No. 26. I have bought these and other tubes on that site for my Radiola.

Steve, check e bay..several on there now, good conductance, checked..great starting bid.

: Is there a tube that can be substituited for a type 26 triode used in a Model 18 Radiola?

: I have looked in the tube substituitions but did not see any listed.

: Is there a tube that can be substituited for a type 26 triode used in a Model 18 Radiola?

: I have looked in the tube substituitions but did not see any listed.

Use a no. 30 tube (2volt fil) in some cases it works
but may hum. To do a good fix use a small bridge rectifier to convert the AC to DC in the filiment circuit put a large capacitor across the out put
and use the no. 30, without a series resistor. Has
worked fine in many cases. 1h4 tube will also work but
needs a new socket or to be rebased. 26 tubes are not
disgustingly expensive though and are still available
from great companies like antique radio supplies in Tempe Arizona.
regards
Ashwick