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PostPosted: Wed Aug 10, 2022 10:39 pm 
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IS going from 50MHz to 100MHz crossing some sort of hard physical line (not that I know of, BTW).

I wanted to source a 100MHz can oscillator as a (sorta) high frequency standard, but the cheapest one I could find was $127!!! A 50MHz oscillator from the same source was 1/33 the price.

That seems like a pretty steep step.

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PostPosted: Wed Aug 10, 2022 11:26 pm 
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Let us know if you find a good PLL solution. I suppose the trouble with PLLs is that the computer would have to write to it to set the frequency; but if it's not running yet, how can it, unless there's a really low-frequency default at which the computer is guaranteed to be able to run before it kicks the frequency up near its maximum dependable limit.

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PostPosted: Thu Aug 11, 2022 12:46 am 
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Actually, I was just looking for stand alone 5V oscillator in a can. They do have them, they just cost a lot. Digikey have them listed to over $3000. Their cheapest is $127.

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PostPosted: Thu Aug 11, 2022 1:13 am 
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It might be because you need 5v, by the time a lot of electronics got over 50 MHz they were mostly running at 3.3v. Some 5v systems that did need a fast clock used a PLL to multiply a 25 or 33 MHz input, for example the MC88915.


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PostPosted: Thu Aug 11, 2022 1:58 am 
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I have a few spares that I bought from China a while back (they were suspiciously inexpensive, but they seem to perform to spec, at least to the extent that my 'scope can validate).

I don't know if I just got lucky, but I'm happy to drop one in the mail if you pm me your address.


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PostPosted: Thu Aug 11, 2022 4:45 am 
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BillO wrote:
Actually, I was just looking for stand alone 5V oscillator in a can.
Perhaps it's the "in a can" aspect that's problematic. At any rate, I had no difficult with price or availability in 2015 when I selected an 80 MHz oscillator in SMD format. (And it's 5V powered.)

I hacked my own mounting, as this was for a through-hole project (wire wrap, in fact) with very little available space.

-- Jeff
Attachment:
adapter for SMD oscillator.jpg
adapter for SMD oscillator.jpg [ 85.88 KiB | Viewed 624 times ]
Attachment:
oscillator hack.png
oscillator hack.png [ 142.63 KiB | Viewed 624 times ]

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PostPosted: Thu Aug 11, 2022 3:44 pm 
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CountChocula wrote:
I have a few spares that I bought from China a while back (they were suspiciously inexpensive, but they seem to perform to spec, at least to the extent that my 'scope can validate).

I don't know if I just got lucky, but I'm happy to drop one in the mail if you pm me your address.

PM sent. Thanks Count!

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PostPosted: Thu Aug 11, 2022 3:45 pm 
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Dr Jefyll wrote:
Perhaps it's the "in a can" aspect that's problematic. At any rate, I had no difficult with price or availability in 2015 when I selected an 80 MHz oscillator in SMD format. (And it's 5V powered.)

I hacked my own mounting, as this was for a through-hole project (wire wrap, in fact) with very little available space.

That's another possibility I could look into.

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