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CGS63 PSU delay not working

CGS63 PSU delay not working

2013-01-18 by Joachim

Hi,

yesterday I tested a PSU (+5V, +/- 15V) with a CGS63 Power Supply Delay but at the and of the relays
I get no voltage. I get +14.2V at pin 6 of the 741 (the output) and nothing at the link near RCO
so my guess is that I have a faulty BC 338. Or is the +14.2V wrong there?

I have also posted this yesterday on Electro Music:
http://www.electro-music.com/forum/viewtopic.php?t=56546

As there is no local store where I could get another BC338 to test my guess I would have to
order it from an online shop so it would be nice if anyone could comment whether the 741 is
behaving as expected.

Cheers
Joachim

Re: CGS63 PSU delay not working

2013-01-18 by cg_synth

Yes, the 741 output should do that to turn the relays on.
Next, look at the collector of the transistor. That should go down to near
zero volts. If it does, then you have problem with the relays, RCD, or the
trackwork between them. If it doesn't, check the emitter really is connected
to ground, and check the resistors between the 741 and the base and groud.
The base should go to about 0.6 or 0.7 volts when the 741 output is at 14.2
volts.

Ken
Show quoted textHide quoted text
>Hi,
>
>yesterday I tested a PSU (+5V, +/- 15V) with a CGS63 Power Supply Delay but
at the and of the relays
>I get no voltage. I get +14.2V at pin 6 of the 741 (the output) and nothing
at the link near RCO
>so my guess is that I have a faulty BC 338. Or is the +14.2V wrong there?
>
>I have also posted this yesterday on Electro Music:
>http://www.electro-music.com/forum/viewtopic.php?t=56546
>
>As there is no local store where I could get another BC338 to test my guess
I would have to
>order it from an online shop so it would be nice if anyone could comment
whether the 741 is
>behaving as expected.
>
>Cheers
>Joachim
>
>
>------------------------------------
>
>The CGS Modular Synth home page: http://www.cgs.synth.net/
>Yahoo! Groups Links
>
>
>
>
_______________________________________________________________________
Ken Stone sasami@... otherunicorn@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

Re: CGS63 PSU delay not working

2013-01-19 by Joachim

Thanks for the answer.

I think the problem is that I have two separate PSU's for +/-15V and +5V
and they are not connected other than through the AC lines and the corresponding
main earth line. I measure 5V between the 'digital' ground of the
+5V PSU and the 'analog' ground of the +/-15V PSU and as the CGS63 utilizes
the +5V line for the relays that is definitely wrong.

Now I'm trying to figure out how I need to connect both PSU's correctly.

Joachim

Am 18.01.2013 21:47, schrieb sasami@...:
Show quoted textHide quoted text
> Yes, the 741 output should do that to turn the relays on.
> Next, look at the collector of the transistor. That should go down to near
> zero volts. If it does, then you have problem with the relays, RCD, or the
> trackwork between them. If it doesn't, check the emitter really is connected
> to ground, and check the resistors between the 741 and the base and groud.
> The base should go to about 0.6 or 0.7 volts when the 741 output is at 14.2
> volts.
>
> Ken
>
>> Hi,
>>
>> yesterday I tested a PSU (+5V, +/- 15V) with a CGS63 Power Supply Delay but
> at the and of the relays
>> I get no voltage. I get +14.2V at pin 6 of the 741 (the output) and nothing
> at the link near RCO
>> so my guess is that I have a faulty BC 338. Or is the +14.2V wrong there?
>>
>> I have also posted this yesterday on Electro Music:
>> http://www.electro-music.com/forum/viewtopic.php?t=56546
>>
>> As there is no local store where I could get another BC338 to test my guess
> I would have to
>> order it from an online shop so it would be nice if anyone could comment
> whether the 741 is
>> behaving as expected.
>>
>> Cheers
>> Joachim
>>
>>
>> ------------------------------------
>>
>> The CGS Modular Synth home page: http://www.cgs.synth.net/
>> Yahoo! Groups Links
>>
>>
>>
>>
> _______________________________________________________________________
> Ken Stone sasami@... otherunicorn@...
> Modular Synth PCBs for sale <http://www.cgs.synth.net/>
> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>
>
>
> ------------------------------------
>
> The CGS Modular Synth home page: http://www.cgs.synth.net/
> Yahoo! Groups Links
>
>
>
>

Re: CGS63 PSU delay not working

2013-01-19 by cg_synth

You need to connect the 0V from the 5v supply to the 0V of the +/-15V supply.

Ken
Show quoted textHide quoted text
>Thanks for the answer.
>
>I think the problem is that I have two separate PSU's for +/-15V and +5V
>and they are not connected other than through the AC lines and the
corresponding
>main earth line. I measure 5V between the 'digital' ground of the
>+5V PSU and the 'analog' ground of the +/-15V PSU and as the CGS63 utilizes
>the +5V line for the relays that is definitely wrong.
>
>Now I'm trying to figure out how I need to connect both PSU's correctly.
>
>Joachim
>
>Am 18.01.2013 21:47, schrieb sasami@...:
>> Yes, the 741 output should do that to turn the relays on.
>> Next, look at the collector of the transistor. That should go down to near
>> zero volts. If it does, then you have problem with the relays, RCD, or the
>> trackwork between them. If it doesn't, check the emitter really is connected
>> to ground, and check the resistors between the 741 and the base and groud.
>> The base should go to about 0.6 or 0.7 volts when the 741 output is at 14.2
>> volts.
>>
>> Ken
>>
>>> Hi,
>>>
>>> yesterday I tested a PSU (+5V, +/- 15V) with a CGS63 Power Supply Delay but
>> at the and of the relays
>>> I get no voltage. I get +14.2V at pin 6 of the 741 (the output) and nothing
>> at the link near RCO
>>> so my guess is that I have a faulty BC 338. Or is the +14.2V wrong there?
>>>
>>> I have also posted this yesterday on Electro Music:
>>> http://www.electro-music.com/forum/viewtopic.php?t=56546
>>>
>>> As there is no local store where I could get another BC338 to test my guess
>> I would have to
>>> order it from an online shop so it would be nice if anyone could comment
>> whether the 741 is
>>> behaving as expected.
>>>
>>> Cheers
>>> Joachim
>>>
>>>
>>> ------------------------------------
>>>
>>> The CGS Modular Synth home page: http://www.cgs.synth.net/
>>> Yahoo! Groups Links
>>>
>>>
>>>
>>>
>> _______________________________________________________________________
>> Ken Stone sasami@... otherunicorn@...
>> Modular Synth PCBs for sale <http://www.cgs.synth.net/>
>> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>>
>>
>>
>> ------------------------------------
>>
>> The CGS Modular Synth home page: http://www.cgs.synth.net/
>> Yahoo! Groups Links
>>
>>
>>
>>
>
>
>
>------------------------------------
>
>The CGS Modular Synth home page: http://www.cgs.synth.net/
>Yahoo! Groups Links
>
>
>
>
_______________________________________________________________________
Ken Stone sasami@... otherunicorn@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

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