[sdiy] Re: quantizer

[peter edwards]

Hello Ray and everyone else who has responded, Thank you for the input!!
I am using an HCF4013 on one of the circuits and a CD4013 on the  
other. both aren't working. I believe that both should work with  
15volt supplies.
The first quantizer I built I made a mistake with the power  
connection and it was only getting ground and -15v.... no +15. Then  
the TL074 burned... so I assumed it the missing +15 was the cause ...  
even though that seemed strange. So I fixed the power and replaced  
the TL074.. same problem. then I replaced each chip one at a time  
with no change. THEN I built the second one and it's the same problem  
with the new circuit... there is no voltage output and the TL074 gets  
hot and burns if I leave it hooked up too long.  I have it configured  
so that I'm feeding an LFO(from the sound lab) going to the input and  
the out is going to the sound lab VCO1 CV input. WHen the quantizer  
circuit is NOT powered, the LFO passes straight through to the VCO.  
When I apply power to the quantizer, the output of the quantizer goes  
to zero. . . all of the chips are in the correct orientation.. the  
power is hooked up correctly and I have have a good, clean power  
supply of exactly +&-15vdc.
-pete


On Jan 8, 2009, at 10:00 AM, Ray Wilson wrote:

> Hi Pete
>
> I have sold quite a few of these boards and no one has reported a  
> problem and mine works fine as well. If the supply is reversed or  
> the chips are in backwards they will get really hot (and need  
> replaced). Other than that I can't think of what could be causing  
> the issue. Are the chips socketed? If so were the sockets oriented  
> correctly? If not are the chips oriented correctly. Check that  
> first and let me know what you find.
>
> Also you must use CD40XX CMOS chips and not 74HCXX or other high  
> speed types because they have power supply limitations. Far more  
> unlikely but possible that both TL074s were bad. All of the chips  
> in the circuit are spec'd for up to 15V. Is your supply putting out  
> more than that?
>
> Do they only get hot when you are connected to another module? What  
> is the resistive load you are driving? Is the output jack wired  
> correctly. If you are putting the output to a hard ground I could  
> see the chip getting hot and you getting no output.
>
> Let me know what you find.
>
> Ray
>
>
>
>
> ----- Original Message ----- From: "peter edwards"  
> <synth at casperelectronics.com>
> To: "Ray Wilson" <raywilson at comcast.net>
> Sent: Thursday, January 08, 2009 3:19 AM
> Subject: quantizer
>
>
>> Hello Ray,
>> I just built 2 quantizers at the same time and they both do not  
>> work. When I plug them in the TL074 IC gets hot. It's the same on  
>> both.
>> I have a good deal of experience building modules, so I don't  
>> think  this is an obvious blunder. I'm using the specified ICs. I  
>> don't get it.
>> Have other people had problems??
>> thanks!
>> -pete
>