aheerfor@...... wrote:

> >
>
> The piano wire is directly attached to the upper main
> frame. I didn't use a turnbuckle.
> ...
> The problem
> is, I can't get the boom in a center position. I didn't get much
> farther. Perhaps the soft soil I live on (clay and sand) causes
> the boom proble,?
> <
>
> No, the problem is the attachment of the wire to the upper main frame.
> The point of attachment has to be slightly displaced towards the wanted
> direction of the boom.
>
> Some kind of screw adjustment of this point is desirable, so that the
> period of oscillation around the center position can be adjusted to 20
> seconds or similar.
>
> Regards, Anders
>

Marchal and Anders,

The above seems like a way to go.  Marchal you could try
drilling the bar through, inserting a bolt and nuts, drill through
the bolt sideways, and reattach the boom wire.  A shaft
coupler could work also, but with the added advantage of
being able to slide up or down the metal bar.  Of course,
adjusting the rear setscrew/s comes into play for period
adjustments also.

Marschal,  if you can center now after repairs, what are you
using for the amplifier, etc.?  The curtain rod you use, is
it solid?  How much weight in the mass? (I've had problems
with the boom/mass ratio with my S-G's)  The key now if 
everything works right is your coil and magnet.

Meredith Lamb

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