> > ? Yes. Also, the orig. shunt resistor was wire wound. The cathodes
> > themselves are c. 27-ohms avg. so a series cathode-resistor is needed to
> > increase the driving Z of the cathodes. Another circuit improvement is to
> > add a ultra fast recovery 1a/400v diode in series with the shunt R. The
> > diode is oriented to prevent current from flowing in the shunt R when the
> > tubes are conducting. This makes for a more balanced load on the radio.
>
> What is the reverse recovery time of the diode you used?
Any idea what the part number of an appropriate device is?
Let's get this strait...from each cathode, we will have a 40 ohm resistor.
The 40 ohm resistors tie together with the 72 ohm shunt resistor and the
input from the exciter. The other end of the shunt resistor goes to ground
through the diode. Is the cathode of the diode tied to the resistor or ground?
(((73)))
Phil, K5PC
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