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Faulty A143-4 vclfo/vco?

Faulty A143-4 vclfo/vco?

2016-07-26 by jaccoville@yahoo.com

Hello Dieter,

While building my new drone station I discovered something odd. 
With all new bought modules there is one which doesn't work properly, an A143-4. 
Now I already own two of them so I compared them with the same (factory) settings, al jumpers in place except for the busCV jumper which I took out. 
With all pots ccw and in LFO mode I slowly turn up the frequency on channel 1. 
There is a big difference between the two modules, one will fully CW in a rather high speed, the other (faulty?) is probably only half that speed. 
In VCO modus this is about the same, the good module goes really high (as it should) the other one stays at medium frequency. 
The only way to get a really high frequency is by putting the common pot cw. 
I tried al channels and checked all jumpers but I don't know what this problem is. 
Please help. 

Best regards

Jacco Ville
The Netherlands

Re: [Doepfer_a100] Faulty A143-4 vclfo/vco?

2016-07-27 by Florian Anwander

On 26.07.16 23:11 , jaccoville@yahoo.com [Doepfer_a100] wrote:
>  except for the busCV jumper which I took out.
If there is an exception, then this is not a comparison.

Have them both setup really the same, then you may find significant results.

AW: [Doepfer_a100] Faulty A143-4 vclfo/vco?

2016-07-27 by yahoo@doepfer.de

Hello Jacco,

all A-143-4 should have a similar frequency range. Maybe the frequency
offsets were not adjusted as prescribed. There are four trimming
potentiometers on the A-143-4 pc board which are labelled "OFFSET 1" ...
"OFFSET 4". These are used to define the frequency offsets. You may try to
adjust the trimming potentiometers of the second module so that they match
to the other module.

Another reason could be a faulty heater. One of the integrated circuits is
equipped with a piggyback heater which warms up the circuit at about 40
degrees Celsius. If the heater is defective this may also cause a different
frequency range (and even the scale is probably off). Simply compare the
temperature of the heaters of the two modules about 10 minutes after power
on by means of touching them with the finger.

Pay also attention that the jumpers for the bus CV are the same for both
modules. Otherwise one of the modules may pick up a CV from the bus which
may cause different frequencies.

Hope this helps
Dieter Doepfer
Show quoted textHide quoted text
> -----Ursprüngliche Nachricht-----
> Von: Doepfer_a100@yahoogroups.com [mailto:Doepfer_a100@yahoogroups.com]
> Gesendet: Dienstag, 26. Juli 2016 23:11
> An: Doepfer_a100@yahoogroups.com
> Betreff: [Doepfer_a100] Faulty A143-4 vclfo/vco?
>
>
> Hello Dieter,
>
> While building my new drone station I discovered something odd.
> With all new bought modules there is one which doesn't work
> properly, an A143-4.
> Now I already own two of them so I compared them with the same
> (factory) settings, al jumpers in place except for the busCV
> jumper which I took out.
> With all pots ccw and in LFO mode I slowly turn up the frequency
> on channel 1.
> There is a big difference between the two modules, one will fully
> CW in a rather high speed, the other (faulty?) is probably only
> half that speed.
> In VCO modus this is about the same, the good module goes really
> high (as it should) the other one stays at medium frequency.
> The only way to get a really high frequency is by putting the
> common pot cw.
> I tried al channels and checked all jumpers but I don't know what
> this problem is.
> Please help.
>
> Best regards
>
> Jacco Ville
> The Netherlands
>
> ------------------------------------
> Posted by: jaccoville@yahoo.com
> ------------------------------------
>
>
> ------------------------------------
>
> Yahoo Groups Links
>
>
>

Re: [Doepfer_a100] Faulty A143-4 vclfo/vco?

2016-07-27 by Jacco Ville

Hello Florian,

My other two A143-4's are  also without the CVBus jumper , don't use the bussystem at all, and they work fine. 
Comparison went 1:1. 

Jacco


Verstuurd vanaf mijn iPhone SE Lunatik 
Show quoted textHide quoted text
> Op 27 jul. 2016 om 09:27 heeft Florian Anwander fanwander@mnet-online.de [Doepfer_a100] <Doepfer_a100@yahoogroups.com> het volgende geschreven:
> 
> On 26.07.16 23:11 , jaccoville@yahoo.com [Doepfer_a100] wrote:
> > except for the busCV jumper which I took out.
> If there is an exception, then this is not a comparison.
> 
> Have them both setup really the same, then you may find significant results.
>

Re: AW: [Doepfer_a100] Faulty A143-4 vclfo/vco?

2016-07-27 by Jacco Ville

Hello Dieter,

I double checked the jumpers and though I didn't measure I felt the piggybag heater was warm. 

I contacted my supplier in Holland and he suggested to send it in. 
Honestly....thank you very much for your reply but I don't want to "experiment" with a brand new module by touching the offsets and messing things up. 

Because I am a bit unpatient I ordered a new one from Thomann. 
Should be there tomorrow. 

Hopefully it will work just as fine as the others. :-)

Thank you again

Best regards 

Jacco Ville
The Netherlands


Verstuurd vanaf mijn iPhone SE Lunatik 
Show quoted textHide quoted text
> Op 27 jul. 2016 om 09:50 heeft yahoo@doepfer.de [Doepfer_a100] <Doepfer_a100@yahoogroups.com> het volgende geschreven:
> 
> Hello Jacco,
> 
> all A-143-4 should have a similar frequency range. Maybe the frequency
> offsets were not adjusted as prescribed. There are four trimming
> potentiometers on the A-143-4 pc board which are labelled "OFFSET 1" ...
> "OFFSET 4". These are used to define the frequency offsets. You may try to
> adjust the trimming potentiometers of the second module so that they match
> to the other module.
> 
> Another reason could be a faulty heater. One of the integrated circuits is
> equipped with a piggyback heater which warms up the circuit at about 40
> degrees Celsius. If the heater is defective this may also cause a different
> frequency range (and even the scale is probably off). Simply compare the
> temperature of the heaters of the two modules about 10 minutes after power
> on by means of touching them with the finger.
> 
> Pay also attention that the jumpers for the bus CV are the same for both
> modules. Otherwise one of the modules may pick up a CV from the bus which
> may cause different frequencies.
> 
> Hope this helps
> Dieter Doepfer
> 
> 
> 
>> -----Ursprüngliche Nachricht-----
>> Von: Doepfer_a100@yahoogroups.com [mailto:Doepfer_a100@yahoogroups.com]
>> Gesendet: Dienstag, 26. Juli 2016 23:11
>> An: Doepfer_a100@yahoogroups.com
>> Betreff: [Doepfer_a100] Faulty A143-4 vclfo/vco?
>> 
>> 
>> Hello Dieter,
>> 
>> While building my new drone station I discovered something odd.
>> With all new bought modules there is one which doesn't work
>> properly, an A143-4.
>> Now I already own two of them so I compared them with the same
>> (factory) settings, al jumpers in place except for the busCV
>> jumper which I took out.
>> With all pots ccw and in LFO mode I slowly turn up the frequency
>> on channel 1.
>> There is a big difference between the two modules, one will fully
>> CW in a rather high speed, the other (faulty?) is probably only
>> half that speed.
>> In VCO modus this is about the same, the good module goes really
>> high (as it should) the other one stays at medium frequency.
>> The only way to get a really high frequency is by putting the
>> common pot cw.
>> I tried al channels and checked all jumpers but I don't know what
>> this problem is.
>> Please help.
>> 
>> Best regards
>> 
>> Jacco Ville
>> The Netherlands
>> 
>> ------------------------------------
>> Posted by: jaccoville@yahoo.com
>> ------------------------------------
>> 
>> 
>> ------------------------------------
>> 
>> Yahoo Groups Links
> 
> 
> 
> ------------------------------------
> 
> ------------------------------------
> 
> 
> ------------------------------------
> 
> Yahoo Groups Links
> 
> 
>

Re: AW: [Doepfer_a100] Faulty A143-4 vclfo/vco?

2016-07-27 by Jacco Ville

-----all A-143-4 should have a similar frequency range. Maybe the frequency
offsets were not adjusted as prescribed-----

Hello Dieter,

What is that prescription?
I mean, are these offset pots some kind of course regulation?
Do I have to use a frequencycounter?

Best regards

Jacco Ville


Verstuurd vanaf mijn iPhone SE Lunatik 
Show quoted textHide quoted text
> Op 27 jul. 2016 om 09:50 heeft yahoo@doepfer.de [Doepfer_a100] <Doepfer_a100@yahoogroups.com> het volgende geschreven:
> 
> Hello Jacco,
> 
> all A-143-4 should have a similar frequency range. Maybe the frequency
> offsets were not adjusted as prescribed

AW: AW: [Doepfer_a100] Faulty A143-4 vclfo/vco?

2016-07-28 by yahoo@doepfer.de

The instructions for the adjustment of the frequency offset is: about 32Hz
in VCO mode with all manual frequency controls at the front panel in center
position (no external CVs via sockets or bus).

Best wishes
Dieter Doepfer
Show quoted textHide quoted text
> -----Ursprungliche Nachricht-----
> Von: Doepfer_a100@yahoogroups.com [mailto:Doepfer_a100@yahoogroups.com]
> Gesendet: Mittwoch, 27. Juli 2016 14:22
> An: Doepfer_a100@yahoogroups.com
> Betreff: Re: AW: [Doepfer_a100] Faulty A143-4 vclfo/vco?
>
>
>
> -----all A-143-4 should have a similar frequency range. Maybe the
> frequency
> offsets were not adjusted as prescribed-----
>
> Hello Dieter,
>
> What is that prescription?
> I mean, are these offset pots some kind of course regulation?
> Do I have to use a frequencycounter?
>
> Best regards
>
> Jacco Ville
>
>
> Verstuurd vanaf mijn iPhone SE Lunatik
>
> > Op 27 jul. 2016 om 09:50 heeft yahoo@doepfer.de [Doepfer_a100]
> <Doepfer_a100@yahoogroups.com> het volgende geschreven:
> >
> > Hello Jacco,
> >
> > all A-143-4 should have a similar frequency range. Maybe the frequency
> > offsets were not adjusted as prescribed
>
>
>
> ------------------------------------
> Posted by: Jacco Ville <jaccoville@yahoo.com>
> ------------------------------------
>
>
> ------------------------------------
>
> Yahoo Groups Links
>
>
>

Re: AW: AW: [Doepfer_a100] Faulty A143-4 vclfo/vco?

2016-07-28 by Jacco Ville

Goodmorning Dieter,

Thank you, it's something I can work with. 

Best regards,

Jacco Ville

Verstuurd vanaf mijn iPhone SE Lunatik 
Show quoted textHide quoted text
> Op 28 jul. 2016 om 09:16 heeft yahoo@doepfer.de [Doepfer_a100] <Doepfer_a100@yahoogroups.com> het volgende geschreven:
> 
> The instructions for the adjustment of the frequency offset is: about 32Hz
> in VCO mode with all manual frequency controls at the front panel in center
> position (no external CVs via sockets or bus).
> 
> Best wishes
> Dieter Doepfer
> 
> > -----Ursprungliche Nachricht-----
> > Von: Doepfer_a100@yahoogroups.com [mailto:Doepfer_a100@yahoogroups.com]
> > Gesendet: Mittwoch, 27. Juli 2016 14:22
> > An: Doepfer_a100@yahoogroups.com
> > Betreff: Re: AW: [Doepfer_a100] Faulty A143-4 vclfo/vco?
> >
> >
> >
> > -----all A-143-4 should have a similar frequency range. Maybe the
> > frequency
> > offsets were not adjusted as prescribed-----
> >
> > Hello Dieter,
> >
> > What is that prescription?
> > I mean, are these offset pots some kind of course regulation?
> > Do I have to use a frequencycounter?
> >
> > Best regards
> >
> > Jacco Ville
> >
> >
> > Verstuurd vanaf mijn iPhone SE Lunatik
> >
> > > Op 27 jul. 2016 om 09:50 heeft yahoo@doepfer.de [Doepfer_a100]
> > <Doepfer_a100@yahoogroups.com> het volgende geschreven:
> > >
> > > Hello Jacco,
> > >
> > > all A-143-4 should have a similar frequency range. Maybe the frequency
> > > offsets were not adjusted as prescribed
> >
> >
> >
> > ------------------------------------
> > Posted by: Jacco Ville <jaccoville@yahoo.com>
> > ------------------------------------
> >
> >
> > ------------------------------------
> >
> > Yahoo Groups Links
> >
> >
> >
> 
>

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