Dear James,
Thank you for the information regarding the "Butterworth"
filters! It's always nice to set things straight. In the
book "Vintage Hi-Fi Spotter's Guide Vol 1" there is a copy
of a Marantz advertisement with an "interview" of Saul
Marantz where he states: "we've developed the first commercial
application of the "Butterworth" or phase-linear filter."
Perhaps this is were the misconception came from.
Several references have been made to a SAE VIB. Is that the
SAE VI with the LED readout? Any other changes? How does a
SAE VI compare with an SAE VIB?
What more can you tell us about the Charlie Tuner? I've only
seen a few fuzzy picures. There seems to be nothing on the
internet about it. What are its specifications and abilities?
Does it have similar or better performance specs when compared
to the 10b?
As you may tell, I really like RF and have restored
Collins R-390a and R-392 series of military HF
receivers.
Best regards,
Paul Bigelow
--- In SAE_Talk@..., James Bongiorno <sstinc@e...> wrote:
Dear Paul,
Probably the biggest misconception about the 10B was the term
coined by some
idiot in Marantz marketing. The 10B (and subsequently the 20 DID
NOT use the
"butterworth" configuration for the IF. Many people have been very
confused
about this over the decades. The 10B used 'LINEAR PHASE FILTERS'
which are
much better. For the uninitiated, the alignment proceedure is a
nightmare.
You must remember that there was an original "10" of which there
were about
100 units made and Marantz would like to forget about that as it
was a sort
of botch. It used torroid ferrites in the IF instead of the pot
cores that
went into the 10B. Anyway, no RF engineer in his right mind would
use the
"butterworth" configuration for the IF as the phase can never be
right.
Unfortunately, the SAE used filters (linear phase) but were sealed
units
from Filtech. Since they were sealed, there were no IF adjustments.
Fortunately the filters were barely acceptable and held up pretty
good over
time. However, they were no match for the 10B.Please bear the
following in
mind. There have been only 3 tuners ever made in this world that
had 18
poles of linear phase filters in the IF: the 10B, the original
Sequerra, and
my "Charlie". This is one of the elements that separates these
three tuners
from all of the rest.
James Bongiorno
Paul Anthony Bigelow wrote:
Dear James,
Those performance specs for the 10b are remarkable (especially
the adjacent figure)! Would the SAE Mk. VI have similar
performance
in this regard? Doesn't the SAE make use of Butterworth filters
in the IF as does the Marantz? Maybe the filters are used in
a scaled down fashion placing the Mk. 6 performace around that
of the Marantz 20b?
My offer to anyone of $1000 for a working Marantz 10b still
stands! (and probably will remain standing for a long time!) :-)
Paul Bigelow
--- In SAE_Talk@..., James Bongiorno <sstinc@e...> wrote:
Dear Paul,
Most people, make that virtually no one, understands the design
of
the 10B
and this is a fact. Even though the stability of the tuner is
quite
remarkable over time, it is very critical in its alignment
proceedures.
There are not 5 people in this country who could properly align
this unit.
If you knew the IF characteristics of the design you would
understand that
closely spaced station interference is practically impossible
with
this
tuner. Correctly aligned, the ADJACENT channel selectivity is a
whopping 38
dB's and the alternate channel selectivity is over 100 dB's.
AND
this is in
NARROW BAND which is the only mode that the 10B operates under.
This is
truly remarkable considering that the 10B makes better specs
and
performance
in its "narrow" band mode than virtually all other tuners in
their
wide band
mode.
James Bongiorno
pbigelow@u... wrote:
Hello James,
I have no first hand knowledge of image problems with
the 10b, I have just encountered reports of problems with
the close spaced signals. The 10b's reported on, of course,
may have needed work or alignment. If I had a properly
restored one, I could answer my own question pretty
quickly.
Anybody out there want to sell me a working Marantz 10b
for $1000? :-)
Paul Bigelow
---------------------------------------------------------------------
---
Get your money connected @ OnMoney.com - the first Web site
that
lets
you see and manage all of your finances all in one place.
---------------------------------------------------------------------
---
Community email addresses:
Post message: SAE_Talk@...
Subscribe: SAE_Talk-subscribe@...
Unsubscribe: SAE_Talk-unsubscribe@...
List owner: SAE_Talk-owner@...
Shortcut URL to this page:
---------------------------------------------------------------------
---
Whatever happened to the class clown? Find out at
Classmates.com,
your online high school class reunion. With 4.4 million alumni
already registered, there's a good chance you'll find him here:
---------------------------------------------------------------------
---
Community email addresses:
Post message: SAE_Talk@...
Subscribe: SAE_Talk-subscribe@...
Unsubscribe: SAE_Talk-unsubscribe@...
List owner: SAE_Talk-owner@...
Shortcut URL to this page:
