[Boatanchors] Viking II Modulator Question

[Gary Schafer]

The Viking II uses a modulation transformer with a little "too high"
secondary impedance. This causes the modulator tubes to go into slight
clipping before 100% modulation is obtained.
The capacitors across the modulation transformer are there to act as a low
pass filter along with the inductance of the transformer. It acts as a
splatter choke.

If you look in some of the older handbooks they talk about "building out" a
modulation transformer with the capacitors to form a low pass filter to
limit splatter. The other way is to add a choke and capacitors after the
modulation transformer.

73
Gary  K4FMX

> -----Original Message-----
> From: boatanchors-bounces at mailman.qth.net [mailto:boatanchors-
> bounces at mailman.qth.net] On Behalf Of Paul Baldock
> Sent: Monday, August 24, 2009 11:42 AM
> To: boatanchors at mailman.qth.net
> Subject: [Boatanchors] Viking II Modulator Question
> 
> The Viking  II modulator has a .001uF Cap across the push -pull
> secondary of the driver transformer and a .01uF Cap across the
> push-pull primary of the mod transformer. Anybody know why?
> 
> Thanks
> 
> - Paul
> 
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