> Z207, assuming it's a 4053B, if missing will
> silence most of the first voice.
Yup. $2.95...
> But the osc B pulse wave should be OK on that voice.
> Syntaur has Polaris keys. Much nicer than gluing the bits
> together...
Yup. That too... It works fine right now. Level and the same playing action as before. BUT - I should get a better key. Further, they are easy to take out and put in. I let that sucka marinate overnight with glue on 2 sides then reinfiorced the inside a little the next day. Nothing more I can do for it and it's right near the spring. :) This keyboard has taken a lickin' and keeps on tickin'...
Any ideas what to test while I wait for the IC? Did the cables and reseated just about everything. Don't want to buy a power supply unless I absolutely need to. BUT - it seems that the batteries and power supplies / transformers were all koo-koo when I started reviving them from stagnation and non-use. Do power supplies / transformers grow old and just die?
Tracy
--------------------------------------------
On Sat, 6/9/18, Tracy Barber adirondack_pc@...
[chromapolaris] <chromapolaris@yahoogroups.com>
wrote:
Subject: Re: [chromapolaris] OK - I Have Diagnostics Now And
They Are Weird
To: chromapolaris@yahoogroups.com
Date: Saturday, June 9, 2018, 1:42 AM
I checked all of the matrix with the
Fluke. Positive results! After a fashion...
The right top board measured in the
3.7x M Ohms range - all of them. The left top board
had some crap in the connector or something. I used
canned air first and then some Deoxy D5. Used the
leads in a consistent fashion and they ranged from 306 -
363
M Ohms. So, this is a good thing.
I had to trim the ribbon cables a
smidgeon and checked if they were even across. After
the Deoxy, they went in a little more than before.
This was the replacement board for the one in it when I
bought it. I think there may have been some Q.A.
issues sending that board out but I won't get into it
here.
Further, broke a key but trusty old
gorilla glue to the rescue!
Reseated EVERY DAMN chip and jumper in
that beast and lost 1 chip. A non-CEM, good
thing... $2.95 for a replacement.
So, the ribbon cables check out so far,
the key is fixed and playable and I've reseated the
entire
mutha... I'll get that chip ASAP because it may
not
work otherwise, unless it simply cuts off one of my 6
channels. Z207 clan...
Now what, boss? Anything I can do
with the chip missing or should I wait?
Tracy
--------------------------------------------
On Fri, 6/1/18, Bob Grieb bobgrieb@...
[chromapolaris] <chromapolaris@yahoogroups.com>
wrote:
Subject: Re: [chromapolaris] OK - I
Have Diagnostics Now And They Are Weird
To: chromapolaris@yahoogroups.com
Date: Friday, June 1, 2018, 4:53 PM
Resistance is
measured in ohms.
You never measure resistance in a
circuit with the power
on.
The meter uses its own current to
measure the resistance.
Any current in the same circuit from
the power being on will
cause an incorrect reading.
I don't think there is anything wrong
with the new
panels.
More likely something else could be
causing a short between
those
two signals. But we haven't
even determined that a
short exists,
it's just a theory at this point.
As I said before, measure the
resistance between other pairs
of SWSTB signals
to see what the resistance measures
(should be high) then
compare that with
the two signals I mentioned.
Maybe you should download the manual
for the meter that you
are using and
review how to use it for simple
measurements?
--------------------------------------------
On Fri, 6/1/18, Tracy Barber adirondack_pc@...
[chromapolaris] <chromapolaris@yahoogroups.com>
wrote:
Subject: Re: [chromapolaris] OK - I
Have Diagnostics Now And
They Are Weird
To: chromapolaris@yahoogroups.com
Date: Friday, June 1, 2018, 2:44
PM
So, stick the lack lead on one
and the red
lead on the other? What Ohms /
Volts will I be looking
for? Anything above 0?
The membranes are pretty tough
now that
Paul redid them. I have to
watch it though because
they have been jiggled around a
bit.
OK, I see - high resistance.
check for high Ohms on the
pairs. Unless I was sold a
bad brand new set of face
"plates", they should
be
fine. Each line in the ribbons
are good, except one
has a small piece missing.
Still 3/4 there.
Try this with the power on?
Since last message, I have
reseated the
connectors and have done so much
with it I should be a
whiz,
but no - just a Dummy for
Electronics. Except for
computers, which are close but
not close enough.
Tracy
--------------------------------------------
On Fri, 6/1/18, Bob Grieb bobgrieb@...
[chromapolaris] <chromapolaris@yahoogroups.com>
wrote:
Subject: Re: [chromapolaris] OK
- I
Have Diagnostics Now And They
Are Weird
To: chromapolaris@yahoogroups.com
Date: Friday, June 1, 2018,
8:50 AM
What I would
suggest is that you use a
multimeter
to see if there is an
electrical
connection
between the two signals that I
mentioned. You can
measure
between other SWSTB pairs
to see what the resistance
should be
(high). I would say
do not unplug the flexes from
the
membranes, or do any cleaning
or
spraying until you have
determined if there is a
problem.
If you find a connection
between those
two signals that
shouldn't be there, then try
to
figure
out where the short is.
But do
your measurements first,
especially since the flexes are
somewhat fragile and you don't
want to
mess with them
any more than absolutely
necessary.
Ideally, you use a meter and
an
oscilloscope to make
measurements that indicate
where problems lie, then you
change
chips, fix traces, etc
to fix the problem.
Bob
--------------------------------------------
On Fri, 6/1/18, Tracy Barber adirondack_pc@...
[chromapolaris]
<chromapolaris@yahoogroups.com>
wrote:
Subject: Re: [chromapolaris] OK
- I
Have Diagnostics Now And
They Are Weird
To: chromapolaris@...m
Date: Friday, June 1, 2018,
12:58 AM
Bob -
I actually have them here.
Section 9 of the service
manual
has the pairs.
That's
where I got the info, from
the
site. You have a good
idea, however... I was
looking
at these but didn't
come up with any way to do
anything with them. Your
example would be "J" and
"K",
vibrato
and pitch pedal, glide
and rate pedal if you put
all
the cross overs together.
So, you're saying check out
the
ribbon
cables again for anything out
of
the ordinary? That I
can do. Clean them with
alcohol, yes?
I sprayed the connectors
with
canned
air and used a little Deoxy
D5
on them to clean them up
already. Made sure they
were
in and lined up
properly.
Unfortunately, I can't check
the
side
that is connected to the
face
plates because they're
buried
under the material. Also,
they're brand new.
Sheesh... I also did the
"S"
curve as told to
by the
video. I sure wished
they would've spent a few more
$
on real connectors. You
also
can't get a swab in
there
to clean the contacts
better.
I wonder if an alcohol
pad would work?
Tracy
****
If you go to this site,
and
scroll
down to the bottom, you
can see the connections
to the
front
panel membrane
switches.
These are not shown in
the
service
manual schematics.
http://www.rhodeschroma.com/?id=polarisserviceschematics
If you look at switches
A and G
you
will see that one end of
each is common, and
only the
other end
is different.
One connects to J9A-3
SWSTB4
and the
other connects to J9A-4
SWSTB5. If
something
is
shorting those two
signals together, such
as a
solder
splash, or possibly a bit
of the old membrane
flex still
in the
connector, then when
you press G, you could
get an
A.
A lot of other pairs
of
switches would also be
joined
by such
a short. I suggest
you troubleshoot the
front
panel issue
and get it resolved
before trying to
troubleshoot
anything
else. A DMM
measuring
resistance should help
to see
if there
is some kind of short
between those two
signals.
Bob
------------------------------------
Posted by: Tracy Barber
<adirondack_pc@...>
------------------------------------
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Re: [chromapolaris] OK - I Have Diagnostics Now And They Are Weird
2018-06-09 by Tracy Barber