6DA5

6DA5 is also designated EM81.

The 6DA5 is an electronic tuning indicator, a cathode-ray tube with an indirect-heated oxide cathode, intended for use as a visual zero or level indicator in AM and FM receivers and other electronic instruments.

Construction

The tube has a base with a minimum of nine contact pins. It is suitable for parallel or series heater supply with AC or DC. The heater is rated at 6.3 V and draws 0.3 A. The datasheet states that the 6DA5 replaces the developmental type 6M40.

Ratings

Maximum ratings include a cold anode voltage of 500 V, a maximum operating anode voltage of 300 V, and a maximum anode dissipation of 0.8 W. The maximum cold screen voltage is 500 V and the maximum operating screen voltage is 300 V. The maximum cathode current is 10 mA. The maximum grid-leak resistance is 3 megohms, and the minimum anode load resistance is 200 kilohms. The maximum voltage between cathode and heater, DC or peak AC, is 100 V, with a maximum external resistance between cathode and heater of 20 kilohms.

Characteristics

The datasheet specifies a characteristic measurement at an anode voltage of 100 V, a screen voltage of 250 V, and a grid bias of −2 V. Under these conditions, the anode current is 0.8 mA and the transconductance is 1.8 mA/V. Input capacitance is given as 2 pF and feedthrough capacitance as 1.5 pF.

Additional operating conditions in the datasheet include a supply voltage of 25 V and a target voltage of 25 V. For one set of conditions, the plate series resistor is 0.5 megohm, the grid series resistor is 3 megohms, the negative grid bias is −1 V, the shadow sector on the target is 65 degrees, the plate current is 0.37 mA, and the target current is 2 mA. For another set of conditions, the negative grid bias is −14 V, the shadow sector is 5 degrees, the plate current is 0.02 mA, and the target current is 2.3 mA.

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 6DA5, hosted by Frank Philipse's Electron Tube Data sheets.

Documents held here and used to write this page.

• Charakteristické hodnoty: (filed under EM81)
• 6DA5