Sensibly equivalent¶ to:
10LD12 28AK8 DH109
The UABC80 is a triple diode triode in a miniature envelope. It can be seen in the photograph that three separate valves exist within the envelope. The triode is at the left, the single diode at the right. In the middle is the double diode, with each half of the box anode insulated from the other.
The UABC80 and its brothers, the 300 mA PABC80 and 6.3 Volt EABC80 were specifically designed for use in the detector stage of early FM and FM/AM radios. Normally this valve featured in a ratio detector circuit for FM demodulation and a diode detector for AM as well as the first stage of audio amplification.
The electrodes seen end on. The thin vertical plate on the left is the heater connection. The three heaters are wired in series.
The reverse side with a clear view of the heater connections.
The triode segment, heater at the left and the grid visible within the anode.
The thin glass tube envelope is 21 mm in diameter, and excluding the B9A base pins, is 58 mm tall.
References: Datasheet, 3002 & 1040. Type UABC80 was first introduced in 1952.
Absolute Maximum Operating Conditions¶
Updated February 03, 2013. shape:thin.glass.tube construction:all.glass type:triple.diode.triode age:1950.1960 base:b9a heater:100ma pins:9 pin:1.a(d3) pin:2.a(d2) pin:3.k(d2) pin:4.h pin:5.h pin:6.a(d1) pin:7.k.k(d1).k(d3) pin:8.g1 pin:9.a