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Z207, assuming it's a 4053B, if missing will silence most of the first voice.
But the osc B pulse wave should be OK on that voice.

Syntaur has Polaris keys. Much nicer than gluing the bits together...

--------------------------------------------
On Sat, 6/9/18, Tracy Barber adirondack_pc@yahoo.com [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@...m>

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@yahoogroups.com

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

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 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

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