1L4

1L4 is also designated DF92.

The 1L4 is a directly heated pentode with fixed slope, intended for RF or AF amplification.

Construction

The 1L4 has direct heating. Its filament can be supplied in parallel at 1.4 V and 50 mA, with filament voltage limits of 1.2 V minimum and 1.6 V maximum. The envelope is type A19-2, and the base is type 7C10. The tube can be mounted in any position.

Ratings

The maximum anode voltage is 120 V, the maximum grid No. 2 voltage is 100 V, and the maximum cathode current is 6.5 mA. The maximum altitude without pressurization is 3 km.

Capacitance and Pinout

Grid No. 1 to anode capacitance is 0.01 pF maximum, input capacitance is 3.6 pF, and output capacitance is 7.5 pF. Pin 1 is connected to the filament negative and internal grid No. 1 shield; pin 2 is the anode; pin 3 is grid No. 2; pin 4 is an internal connection; pin 5 is connected to the filament negative and internal grid No. 3 shield; pin 6 is grid No. 1; and pin 7 is the filament positive.

Equivalence is asserted only where the archive's own literature states it directly, in at least 40 separate documents. Tubes that merely substitute in some circuits are not listed here.

Original manufacturer datasheets for 1L4, hosted by Frank Philipse's Electron Tube Data sheets.

Documents held here and used to write this page.

• Capacités interélectrodes (sans blindage extérieur)
• "Miniwatt" (filed under DF92)

1 further designation appears alongside 1L4 in the literature but below the evidence threshold used here, so it is not listed as equivalent.