On Jul 16, 4:48*am, "Antonio Vernucci" wrote:
Mine has the same behavior, and the technical manual says that it's the way it
works so no problem.

Furthermore it seems rather logical as in A.M. mode the H.T.s are only
required when the mike paddle is depressed... The dynamotor speed settle time
is acceptable in this mode but try to figure out the dynamotor being turned on
and off at the keying speed in CW!

Hope this helps,

Thierry
--

Thanks for information. OK for CW, though for AM it gives me a strange feeling
to hear the dynamotor starting every time I push the microphone PTT. In the
BC-191 / BC 375 the dynamotor instead runs continuously, either CW or AM.

I have built an AC power supply for my ART-13 and I must now adapt its control
logic to that of the ART-13, which is not immediate to understand because the
schematic diagram is not easy to read (so many relays ...) and the service
manual describes things using a rather odd sentence structure, difficult to
follow. I do not succeed to get the antenna relay energized in any way, so I
fear I'll have quite a hard time in the near future to have it in working order.

73

Tony I0JX
Rome, Italy

I have the ART-13's 1950s descendant, the Collins 618S (ARC-38). This
has the same dynamotor behavior as the ART-13 - it runs continuously
when in CW mode. This is quite normal; when in AM mode the dynamotor
runs *only* in xmit mode. In the 618S B+ voltages for the xmit and
modulator
are generated by the dynamotor, B+ (and B-) for the rest of the system
is derived from the 115V 400 Hz supply. On my 618S I run the filaments
from a filtered 27.5V DC supply, the dynamotor from raw DC. This is
accomplished by minor rewiring of the 416W-1 power supply; it's
probably easier on an ART-13.

John VK3XAO