[ARC5] Fall Project: Navy ATD Transmitter, Part 2

[AKLDGUY .]

On Wed, Oct 11, 2017 at 6:55 PM, David Stinson <arc5 at ix.netcom.com> wrote:

> Re:  Fall Project: Navy ATD Transmitter Part 2


> The dual .1 uFd, C-107, leaked
> badly.  This cap is rated at 600V, but it's across
> the filament of the MO, V101 and the common of the
> two caps goes to the tap on the MO tank, not
> ground, so a smaller DC voltage rating will work.

The 600V rating may have been chosen because there may be relay windings
across
the filament line, just as there are in the Command transmitters. The
capacitors may be
intended to suppress the back EMF or voltage spike when the relays are
turned off.
If the capacitors are not connected or are non-functioning, there may be a
risk of heater
to cathode breakdown in the tubes.

Neil ZL1ANM
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