12SK7 requires 12 volts on the filament, 6SK7 6 volts. A 12SK7 probably won't work. Even if it does the radio will take a long time to play and won't be as good as it should.
Norm
:what is difference between 12sk7 tube and 6sk7 tube iam restoring 1946 farnsworth eo66 and have found 12sk7 in place of 6sk7
Don't put a 6SK7 in your radio until you read this first.
Are you talking about the Farnsworth ET-066? That model is an AC/DC radio that uses two 6SS7 tubes, not 6SK7 tubes. (There is a total of 6 tubes, including a 12SA7, a 12SQ7, a 50L6 and a 35Z5.)
With AC/DC sets, the heater current (in this case 150 milliamps) is equally critical. All heaters in the string MUST have the same current rating. The 6SS7 has a 150 ma heater, while the 6SK7 has a 300 ma heater. Using a 6SK7 will put stress on the heaters in the string. However, replacing one 6SS7 with a 12SK7 (which has a 150 ma heater) will raise the heater string voltage 122.8 volts to 129.1 volts.
Although this is high, it won't stress the heater string. It will, however, lower the voltage supplied to each heater, causing the radio to function weakly. Therefore, if this is a model ET-066, using 6SS7 tubes is prefered.
:Hi Wilton
:
: 12SK7 requires 12 volts on the filament, 6SK7 6 volts. A 12SK7 probably won't work. Even if it does the radio will take a long time to play and won't be as good as it should.
:
:Norm
:
:
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: :what is difference between 12sk7 tube and 6sk7 tube iam restoring 1946 farnsworth eo66 and have found 12sk7 in place of 6sk7
Agree with Steven, since this is an AC/DC radio, filaments wired in series, 6SS7 and 12SK7 would be interchangeable. I was going by tubes mentioned in your posting and not radio type. In this case 6SK7 is not acceptable.
Norm
:Wilton
:
:Don't put a 6SK7 in your radio until you read this first.
:
:Are you talking about the Farnsworth ET-066? That model is an AC/DC radio that uses two 6SS7 tubes, not 6SK7 tubes. (There is a total of 6 tubes, including a 12SA7, a 12SQ7, a 50L6 and a 35Z5.)
:
:With AC/DC sets, the heater current (in this case 150 milliamps) is equally critical. All heaters in the string MUST have the same current rating. The 6SS7 has a 150 ma heater, while the 6SK7 has a 300 ma heater. Using a 6SK7 will put stress on the heaters in the string. However, replacing one 6SS7 with a 12SK7 (which has a 150 ma heater) will raise the heater string voltage 122.8 volts to 129.1 volts.
:
:Although this is high, it won't stress the heater string. It will, however, lower the voltage supplied to each heater, causing the radio to function weakly. Therefore, if this is a model ET-066, using 6SS7 tubes is prefered.
:
::Hi Wilton
::
:: 12SK7 requires 12 volts on the filament, 6SK7 6 volts. A 12SK7 probably won't work. Even if it does the radio will take a long time to play and won't be as good as it should.
::
::Norm
::
::
::
:: :what is difference between 12sk7 tube and 6sk7 tube iam restoring 1946 farnsworth eo66 and have found 12sk7 in place of 6sk7