[sdiy] Difficult 2164 behaviour between different sections.

[Erik Dower]

I was thinking that might be the way to go. On my circuit, there is a very small amount of fm happening when the gain cell is attenuating, but a very distinct jump in frequency once it starts amplifying.

epk

> On Jul 15, 2019, at 4:57 PM, Tom Bugs <admin at bugbrand.co.uk> wrote:
> 
> I didn't exactly - I rejigged things so that different sections were used for the critical parts.
> 
> Best, Tom
> 
> On 14/07/2019 21:05, Erik Dower wrote:
>> Hi Tom,
>> 
>> Did you ever resolve this issue? Unfortunately I find myself in a similar situation.
>> 
>> Thanks,
>> 
>> epk
>> 
>>> On May 30, 2018, at 10:29 PM, Tom Bugs <admin at bugbrand.co.uk> wrote:
>>> 
>>> Thanks all.
>>> 
>>> Beefing up the 0V is something I tried on another point of the circuit, but I don't think I tried it on the 0V pin itself - good point!
>>> 
>>> I will try Rbias some more for sure.
>>> 
>>> And agree with many of the points from David - it has been an eye opener & I will have a few more deep sessions with it.
>>> 
>>> I'll report back..
>>> 
>>> Cheers - Tom
>>> 
>>> 
>>> On 30/05/2018 19:41, David G Dixon wrote:
>>>> That's an excellent idea.  I was thinking something similar, because if
>>>> there is any external impedance at that pin, then those control inputs are
>>>> going to interact because of those internal 5k impedances.  That's probably
>>>> the issue -- your ground isn't really ground.
>>>> 
>>>>> -----Original Message-----
>>>>> From: Synth-diy [mailto:synth-diy-bounces at synth-diy.org] On
>>>>> Behalf Of Oakley Sound
>>>>> Sent: Wednesday, May 30, 2018 9:11 AM
>>>>> To: Synth DIY
>>>>> Subject: Re: [sdiy] Difficult 2164 behaviour between
>>>>> different sections.
>>>>> 
>>>>> It could well be internal to the 2164 but have you tried
>>>>> lowering the the resistance to the 0V pin? Temporarily cludge
>>>>> a ruddy big wire from the PSU's 0V directly to pin 8, in
>>>>> parallel with what you've already got on the board, and see
>>>>> what happens.
>>>>> 
>>>>> Tony
>>>>> 
>>>>> www.oakleysound.com
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