[BC] "Cusp Rotation"

[Phil Alexander]

On 16 Mar 2007 at 9:48, Kent Winrich wrote:

> You are expecting the manufacturers to provide this info??? 
> HAHAHAHA  They dont know half of what they put out.  

Actually, at least some of them will measure the exact value
for you in test. AFAIK all of the majors have published, or
will supply their average numbers on request. My concern is
finding a DYNAMIC way to hit the match - much like we do with
a CPB for impedance. Every time you tweak a phasor, there is
a chance of upsetting rotation. Think about that one for awhile
and you'll see where I'm coming from.

 
> I like the idea of your Vector analyzer.  Sure would be easier than 
> going through the OIB and what have you that I did for my two HD 
> installs.  UGH.

Ron Rackely has the answer to that, but you still have to take the
station down for a time to use it. The equipment Ron uses in
addition to the RF amp and analyzer can be found on Steve Tunwall's
site. It is the best thing we have so far, but read the first
sentence of this paragraph again and think about running a set of
MP's only to find one or two out of limit. Then think about the
possible effect of the adjustments on rotation. This is not a
pretty thought.

---------------------------------------------
Phil Alexander, CSRE, AMD
Broadcast Engineering Services and Technology 
(a Div. of Advanced Parts Corporation) 
Ph. (317) 335-2065   FAX (317) 335-9037