strange oscillator

On Monday, February 7, 2022 at 10:06:30 AM UTC+11, jla...@highlandsniptechnology.com wrote:
> On Sun, 06 Feb 2022 19:11:27 GMT, Jan Panteltje <pNaonSt...@yahoo.com> wrote: 
> >On a sunny day (Sun, 06 Feb 2022 09:54:32 -0800) it happened John Larkin <jjla...@highlandtechnology.com> wrote in <sr9qvg5gc3rues8uv...@4ax.com>:  
> >>On Fri, 04 Feb 2022 07:19:08 GMT, Jan Panteltje <pNaonSt...@yahoo.com> wrote: 
> >>>On a sunny day (Thu, 03 Feb 2022 15:58:32 -0800) it happened John Larkin <jjla...@highlandtechnology.com> wrote in <l61ovg5sopebot77r...@4ax.com>: 

<snip>

> >The twisted wire is cheaper :-)
>
> A PCB transmission line oscillator would be OK, I guess.

Jan wasn't exactly using a long length of twisted pair - it looked more like a capacitor than a delay line.

Twisted pair delay line is cheaper (in small quantities) than a purpose built PCB, an would probably work at 1.5GHz.

-- 
Bill Sloman, Sydney

On a sunny day (Sun, 06 Feb 2022 15:06:15 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
<2ok00hhf4nvrtvhap8oakeo98lpmcsodtq@4ax.com>:

>A PCB transmission line oscillator would be OK, I guess.

Probably.

I am using the ADF4350 in some project,
output frequency range: 137.5 MHz to 4400 MHz:
 http://panteltje.com/panteltje/newsflex/download.html#ADF4350_test
 has differential RF out,
10 for 9$49 on ebay
?

complete evaluation board, I have it:
 https://www.ebay.com/itm/264492637509
10 USD

Chip needs some wires from your FPGA for programming though
and some reference frequency around < 30MHz IIRC.

https://www.ebay.com/itm/174058719176

On Mon, 07 Feb 2022 05:19:16 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

>On a sunny day (Sun, 06 Feb 2022 15:06:15 -0800) it happened
>jlarkin@highlandsniptechnology.com wrote in
><2ok00hhf4nvrtvhap8oakeo98lpmcsodtq@4ax.com>:
>
>>A PCB transmission line oscillator would be OK, I guess.
>
>Probably.
>
>I am using the ADF4350 in some project,
>output frequency range: 137.5 MHz to 4400 MHz:
> http://panteltje.com/panteltje/newsflex/download.html#ADF4350_test
> has differential RF out,
>10 for 9$49 on ebay
>?
>
>complete evaluation board, I have it:
> https://www.ebay.com/itm/264492637509
>10 USD
>
>Chip needs some wires from your FPGA for programming though
>and some reference frequency around < 30MHz IIRC.
>
>

We use LMX2571, a really nice synthesizer. It only costs $7.50 but
it's kind of a big deal to use. We had to write the driver from
scratch and it was ugly. It wouldn't be so bad to program at one fixed
frequency, but would still need a uP or an FPGA and code. I just want
a tiny reasonably stable complementary 1.5 GHz clock.

The 10EP11 naturally oscillates at about 1.5G, with outputs connected
directly to inputs inverted, basically a prop delay oscillator. I
wonder if it can be persuaded to oscillate more predictably with an LC
tank in the loop. Maybe even above 1.5G.





-- 

I yam what I yam - Popeye