[Collins] Bucking Voltage

[David Knepper]

The consensus from Peter, K2LRC, and Heinz is that the secondary voltage
from the 516F-2 power transformer as a bucking winding is too small to get
any kind of primary reduction voltage.

See the response below from Heinz

Dave, W3ST
Secretary to the Collins Radio Association
Publisher of the Collins Journal
www.collinsra.com
----- Original Message -----
From: "Heinz und Hannelore Breuer" <hbreuer@debitel.net>
To: "David Knepper" <cra@floodcity.net>
Cc: <collins@mailman.qth.net>
Sent: Sunday, November 09, 2003 2:08 PM
Subject: Re: [Collins] Bucking Voltage


> Hi Dave,
>
> this topic "Bucking transformer" has been discussed on various
> boatanchor lists several times. I just don't remember if it showed up
> here before.
>
> A 5V transformer is too small. Better take a 10V or even a 12,6 V
> filament transformer. Most line voltages are running at 125V or even
> higher. Getting it down by 10V or even more would be for the benefit of
> the transformers. The A-line might have been made with a 110V primary
> back then.
>
> Choose a transformer with a secondary current rating high enough to run
> the primary current of the Collins unit you want to use. Connect the
> secondary of this transformer in serial with the primary of the Collins
> unit. Connect the primary to the line voltage. Just make sure it "bucks"
> the voltage and does not "step it up". If it steps up just change the
> wires.I made an external box containing the bucking transformer, it has
> a power cord which goes to the power outlet in the wall and also an
> outlet where I plug in my unit which I want to run on a reduced line
voltage.
>
> 73
> Heinz DH2FA, KM5VT
>
>
>
>
> David Knepper wrote:
> >
> > Someone mentioned that they use the unused 5 volt secondary winding to
buck
> > the primary voltage in an HT-37.  I wonder if the same could be done
with
> > the power transformer in the Collins 516F-2.
> >
> > I wonder why this trick circuitry has not been discussed before to
reduce
> > the A.C. voltage on the primary, thus, giving some relief to the
transformer
> > from the over 120 volt line voltage in many areas.
> >
> > Thank you.
> >
> > Dave, W3ST
> > Secretary to the Collins Radio Association
> > Publisher of the Collins Journal
> > www.collinsra.com