[sdiy] Hi frequency VC clock

[rsdio at audiobanshee.com]

Hi Mike,

That is, indeed, the most recent message in the thread. I am very interested in this topic, because I've started on a design that need just such a clock. However, I haven't even started reviewing the many references provided in the thread so far, so I didn't really worry when the topic fizzled out.

There's so much traffic on AH that I didn't notice how quiet SDIY has been.

Brian


On Jun 23, 2017, at 10:48 AM, Mike HEQX <mike at heqx.com> wrote:
> Is this the last communication that anyone sent? Have not seen anything else for a couple of days. Starting to worry that I am not getting anything from the list at all.
> 
> On 6/21/2017 9:18 AM, Steve Lenham wrote:
>> On 21/06/2017 12:25, Tom Wiltshire wrote:
>>> The reasons are pretty straightforward:
>>> 
>>> 1) Cheap
>>> 2) Available
>>> 3) VCO to 10+MHz.
>>> 
>>> Find me another chip that fulfils the above criteria and I'll use it! ;)
>> 
>> 74LS624/628/629?
>> 
>> Venerable but still in production, which perhaps says something.
>> Cheap-ish (though not as cheap as a 4046).
>> Good for 25MHz if you want but can go low too.
>> Still intended as PLL VCOs (so linear) but the OP wanted something to act as a sweepable clock generator, not an expo VCO. A device from this family (74S124, also still available but loves current) is used for that very purpose in the original Lexicon Prime Time delay, with triangle wave modulation.
>> 
>> Cheers,
>> 
>> Steve L.
>> Benden Sound Technology
>