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Don't know if the original caps were polar or bi-polar (E-II)

Don't know if the original caps were polar or bi-polar (E-II)

2012-12-10 by Gil

I have a nice Emulator II which doesn't sample from the day I got it.

You see no signal when playing into the input (using another synth, or an electric guitar). 

I decided to investigate this and found that what seems to be the sampling circuit, has two electrolyte caps, which on the schematics are marked as "alum-electro (nonpolar) 4.7uf" but on the actual board,  regular POLAR caps are used. These caps I put myself when recapping the machine.

I tend to think that this causes the sampling circuit not to work,
BUT - a closer look at the board reveals a + sign near each of these two caps, as if the engineers did intend to use regular POLAR caps there... 

I'm afraid to replace them with non-polars so I don't damage the circuit ..... Any advice ?

You can see the diagram at page 42 of the manual, here:

http://www.synthesizerarchiv.de/circuits/emu/emulator2_circuits/emulator2_circuits.pdf

Thanks !

RE: [vintagesynthrepair] Don't know if the original caps were polar or bi-polar (E-II)

2012-12-10 by Brian

You can replace with non-polar without any problem

 

Regards

Brian G3OYU
Show quoted textHide quoted text
From: vintagesynthrepair@yahoogroups.com
[mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of Gil
Sent: 10 December 2012 1:13
To: vintagesynthrepair@yahoogroups.com
Subject: [vintagesynthrepair] Don't know if the original caps were polar or
bi-polar (E-II)

 

  

I have a nice Emulator II which doesn't sample from the day I got it.

You see no signal when playing into the input (using another synth, or an
electric guitar). 

I decided to investigate this and found that what seems to be the sampling
circuit, has two electrolyte caps, which on the schematics are marked as
"alum-electro (nonpolar) 4.7uf" but on the actual board, regular POLAR caps
are used. These caps I put myself when recapping the machine.

I tend to think that this causes the sampling circuit not to work,
BUT - a closer look at the board reveals a + sign near each of these two
caps, as if the engineers did intend to use regular POLAR caps there... 

I'm afraid to replace them with non-polars so I don't damage the circuit
..... Any advice ?

You can see the diagram at page 42 of the manual, here:

http://www.synthesizerarchiv.de/circuits/emu/emulator2_circuits/emulator2_ci
rcuits.pdf

Thanks !

Re: Don't know if the original caps were polar or bi-polar (E-II)

2012-12-11 by Gil

Thanks,

I replaced them with bi-polars, no change in behavior (works just as before, no sample in signal).

What do you think ? should I keep the bi-polars there, or switch back to the polars ?

As I said before, the schematics calls for bi-polars, but the on the circuit board there are + signs near each cap, implying for polar capacitors... Why would they mark the polarity on the board if they ask for non-polar caps there ?

Just wondering...



--- In vintagesynthrepair@yahoogroups.com, "Brian" <brian@...> wrote:
Show quoted textHide quoted text
>
> You can replace with non-polar without any problem
> 
>  
> 
> Regards
> 
> Brian G3OYU
> 
>  
> 
> From: vintagesynthrepair@yahoogroups.com
> [mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of Gil
> Sent: 10 December 2012 1:13
> To: vintagesynthrepair@yahoogroups.com
> Subject: [vintagesynthrepair] Don't know if the original caps were polar or
> bi-polar (E-II)
> 
>  
> 
>   
> 
> I have a nice Emulator II which doesn't sample from the day I got it.
> 
> You see no signal when playing into the input (using another synth, or an
> electric guitar). 
> 
> I decided to investigate this and found that what seems to be the sampling
> circuit, has two electrolyte caps, which on the schematics are marked as
> "alum-electro (nonpolar) 4.7uf" but on the actual board, regular POLAR caps
> are used. These caps I put myself when recapping the machine.
> 
> I tend to think that this causes the sampling circuit not to work,
> BUT - a closer look at the board reveals a + sign near each of these two
> caps, as if the engineers did intend to use regular POLAR caps there... 
> 
> I'm afraid to replace them with non-polars so I don't damage the circuit
> ..... Any advice ?
> 
> You can see the diagram at page 42 of the manual, here:
> 
> http://www.synthesizerarchiv.de/circuits/emu/emulator2_circuits/emulator2_ci
> rcuits.pdf
> 
> Thanks !
>

RE: [vintagesynthrepair] Re: Don't know if the original caps were polar or bi-polar (E-II)

2012-12-11 by Brian

Some non-polar caps do have a positive and negative marking, don't ask me
why I don't know.  You would need to consult the schematic to ascertain
whether or not the caps get reverse polarity volts on them at any time.

Regards

Brian G3OYU

 

From: vintagesynthrepair@yahoogroups.com
[mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of Gil
Sent: 11 December 2012 9:07
To: vintagesynthrepair@yahoogroups.com
Subject: [vintagesynthrepair] Re: Don't know if the original caps were polar
or bi-polar (E-II)

 

  


Thanks,

I replaced them with bi-polars, no change in behavior (works just as before,
no sample in signal).

What do you think ? should I keep the bi-polars there, or switch back to the
polars ?

As I said before, the schematics calls for bi-polars, but the on the circuit
board there are + signs near each cap, implying for polar capacitors... Why
would they mark the polarity on the board if they ask for non-polar caps
there ?

Just wondering...

--- In vintagesynthrepair@yahoogroups.com
<mailto:vintagesynthrepair%40yahoogroups.com> , "Brian" <brian@...> wrote:
>
> You can replace with non-polar without any problem
> 
> 
> 
> Regards
> 
> Brian G3OYU
> 
> 
> 
> From: vintagesynthrepair@yahoogroups.com
<mailto:vintagesynthrepair%40yahoogroups.com> 
> [mailto:vintagesynthrepair@yahoogroups.com
<mailto:vintagesynthrepair%40yahoogroups.com> ] On Behalf Of Gil
> Sent: 10 December 2012 1:13
> To: vintagesynthrepair@yahoogroups.com
<mailto:vintagesynthrepair%40yahoogroups.com> 
> Subject: [vintagesynthrepair] Don't know if the original caps were polar
or
> bi-polar (E-II)
> 
> 
> 
> 
> 
> I have a nice Emulator II which doesn't sample from the day I got it.
> 
> You see no signal when playing into the input (using another synth, or an
> electric guitar). 
> 
> I decided to investigate this and found that what seems to be the sampling
> circuit, has two electrolyte caps, which on the schematics are marked as
> "alum-electro (nonpolar) 4.7uf" but on the actual board, regular POLAR
caps
> are used. These caps I put myself when recapping the machine.
> 
> I tend to think that this causes the sampling circuit not to work,
> BUT - a closer look at the board reveals a + sign near each of these two
> caps, as if the engineers did intend to use regular POLAR caps there... 
> 
> I'm afraid to replace them with non-polars so I don't damage the circuit
> ..... Any advice ?
> 
> You can see the diagram at page 42 of the manual, here:
> 
>
http://www.synthesizerarchiv.de/circuits/emu/emulator2_circuits/emulator2_ci
Show quoted textHide quoted text
> rcuits.pdf
> 
> Thanks !
>

Re: [vintagesynthrepair] Re: Don't know if the original caps were polar or bi-polar (E-II)

2012-12-11 by Kim Günther Hansen

Try this forum – maybe someone there knows

http://eiiiforum.com/index.php?PHPSESSID=j4a0c6j5hbbd0jkj1lvc5k24p4&board=5.0

Kim

Show quoted textHide quoted text
From: Brian <brian@....uk>
Reply-To: "vintagesynthrepair@yahoogroups.com" <vintagesynthrepair@yahoogroups.com>
Date: Tue, 11 Dec 2012 16:16:26 +0100
To: "vintagesynthrepair@yahoogroups.com" <vintagesynthrepair@yahoogroups.com>
Subject: RE: [vintagesynthrepair] Re: Don't know if the original caps were polar or bi-polar (E-II)

Some non-polar caps do have a positive and negative marking, don’t ask me why I don’t know. You would need to consult the schematic to ascertain whether or not the caps get reverse polarity volts on them at any time.

Regards

Brian G3OYU

From: vintagesynthrepair@yahoogroups.com [mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of Gil
Sent: 11 December 2012 9:07
T o: vintagesynthrepair@yahoogroups.com
Subject: [vintagesynthrepair] Re: Don't know if the original caps were polar or bi-polar (E-II)


Thanks,

I replaced them with bi-polars, no change in behavior (works just as before, no sample in signal).

What do you think ? should I keep the bi-polars there, or switch back to the polars ?

As I said before, the schematics calls for bi-polars, but the on the circuit board there are + signs near each cap, implying for polar capacitors... Why would they mark the polarity on the board if they ask for non-polar caps there ?

Just wondering...

--- In vintagesynthrepair@yahoogroups.com, "Brian" <brian@...> wrote:
>
> ; You can replace with non-polar without any problem
>
>
>
> Regards
>
>; Brian G3OYU
>
>
>
> From: vintagesynthrepair@yahoogroups.com
> [mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of Gil
> Sent: 10 December 2012 1:13
> To: vintagesynthrepair@yahoogroups.com
> Subject: [vintagesynthrepair] Don't know if the original caps were polar or
> bi-polar (E-II)
>
>
>
>
>
> I have a nice Emulator II which doesn't sample from the day I got it.
>
> You see no signal when playing into the input (using another synth, or an
>; electric guitar).
>
> I decided to investigate this and found that what seems to be the sampling
> circuit, has t wo electrolyte caps, which on the schematics are marked as
> "alum-electro (nonpolar) 4.7uf" but on the actual board, regular POLAR caps
> are used. These caps I put myself when recapping the machine.
>
>; I tend to think that this causes the sampling circuit not to work,
>; BUT - a closer look at the board reveals a + sign near each of these two
> caps, as if the engineers did intend to use regular POLAR caps there...
>
> I'm afraid to replace them with non-polars so I don't damage the circuit
> ..... Any advice ?
>
> You can see the diagram at page 42 of the manual, here:
>
> http://www.synthesizerarchiv.de/circuits/emu/emulator2_circuits/emulator2_ci
> rcuits.pdf
>
> Thanks !
>

Re: Don't know if the original caps were polar or bi-polar (E-II)

2012-12-15 by Gil

The board has the marking... not the non polar caps :/

It has the positive marks near each of the location where the non polar caps should go. This is what causes the confusion...
(scheme says non polar but there are marks on the board)



--- In vintagesynthrepair@yahoogroups.com, "Brian" <brian@...> wrote:
Show quoted textHide quoted text
>
> Some non-polar caps do have a positive and negative marking, don't ask me
> why I don't know.  You would need to consult the schematic to ascertain
> whether or not the caps get reverse polarity volts on them at any time.
> 
> Regards
> 
> Brian G3OYU
> 
>  
> 
> From: vintagesynthrepair@yahoogroups.com
> [mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of Gil
> Sent: 11 December 2012 9:07
> To: vintagesynthrepair@yahoogroups.com
> Subject: [vintagesynthrepair] Re: Don't know if the original caps were polar
> or bi-polar (E-II)
> 
>  
> 
>   
> 
> 
> Thanks,
> 
> I replaced them with bi-polars, no change in behavior (works just as before,
> no sample in signal).
> 
> What do you think ? should I keep the bi-polars there, or switch back to the
> polars ?
> 
> As I said before, the schematics calls for bi-polars, but the on the circuit
> board there are + signs near each cap, implying for polar capacitors... Why
> would they mark the polarity on the board if they ask for non-polar caps
> there ?
> 
> Just wondering...
> 
> --- In vintagesynthrepair@yahoogroups.com
> <mailto:vintagesynthrepair%40yahoogroups.com> , "Brian" <brian@> wrote:
> >
> > You can replace with non-polar without any problem
> > 
> > 
> > 
> > Regards
> > 
> > Brian G3OYU
> > 
> > 
> > 
> > From: vintagesynthrepair@yahoogroups.com
> <mailto:vintagesynthrepair%40yahoogroups.com> 
> > [mailto:vintagesynthrepair@yahoogroups.com
> <mailto:vintagesynthrepair%40yahoogroups.com> ] On Behalf Of Gil
> > Sent: 10 December 2012 1:13
> > To: vintagesynthrepair@yahoogroups.com
> <mailto:vintagesynthrepair%40yahoogroups.com> 
> > Subject: [vintagesynthrepair] Don't know if the original caps were polar
> or
> > bi-polar (E-II)
> > 
> > 
> > 
> > 
> > 
> > I have a nice Emulator II which doesn't sample from the day I got it.
> > 
> > You see no signal when playing into the input (using another synth, or an
> > electric guitar). 
> > 
> > I decided to investigate this and found that what seems to be the sampling
> > circuit, has two electrolyte caps, which on the schematics are marked as
> > "alum-electro (nonpolar) 4.7uf" but on the actual board, regular POLAR
> caps
> > are used. These caps I put myself when recapping the machine.
> > 
> > I tend to think that this causes the sampling circuit not to work,
> > BUT - a closer look at the board reveals a + sign near each of these two
> > caps, as if the engineers did intend to use regular POLAR caps there... 
> > 
> > I'm afraid to replace them with non-polars so I don't damage the circuit
> > ..... Any advice ?
> > 
> > You can see the diagram at page 42 of the manual, here:
> > 
> >
> http://www.synthesizerarchiv.de/circuits/emu/emulator2_circuits/emulator2_ci
> > rcuits.pdf
> > 
> > Thanks !
> >
>

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