80s are Temporarily out-of-stock and will ship as soon as they arrive.
The 80 was originally intended for radios or small amplifiers. This diode is a somewhat smaller version than the 5U4G, intended for lower DC output current, and lower voltage. The maximum value for the capacitor is 20uF, which is lower than with 5U4G, however since the 80 is intended for maximum 135mA, the value of 20uA is sufficient. Output ripple is also lower because of higher Anode impedance of this tube. It must be said if you are working at the lower current such as below 135mA, the 80 is a very good choice.
For ultra low ripple, it is recommended to use the Lundahl LL1673 dual coil choke in low CMR configuration. In this configuration, there is virtually no field radiation from the choke. (See link to circuit diagram, at the bottom of this page).
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