Cgs synth

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

Ken

>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/>