Path: ...!local-4.nntp.ord.giganews.com!Xl.tags.giganews.com!local-1.nntp.ord.giganews.com!nntp.supernews.com!news.supernews.com.POSTED!not-for-mail
NNTP-Posting-Date: Fri, 31 May 2024 11:40:05 +0000
From: john larkin <jl@650pot.com>
Newsgroups: sci.electronics.design
Subject: Re: Yttrium iron garnet
Date: Fri, 31 May 2024 04:40:05 -0700
Message-ID: <s9dj5jpr1somh4kmc7if7pcddm3ji4kd1j@4ax.com>
References: <v368qb$106vv$1@dont-email.me> <v37nll$17q1d$2@dont-email.me> <cipe5jtcttecs7r5k9pngm94gqseoo913u@4ax.com> <v393pp$1ihhr$1@dont-email.me> <v39g2i$1kegm$1@dont-email.me> <X1Z5O.409$Ktt5.58@fx40.iad> <n71h5j5ls6v3u75eg8gr6sni800upq5l4i@4ax.com> <v3as3c$1s3ma$1@dont-email.me> <q1th5j1kttmnuc2dd0p97831dejitku55e@4ax.com> <v3b46v$1td5u$1@dont-email.me> <ir9j5j983n81lq4erqer68lhrgr2u95jmn@4ax.com> <v3cc62$2720o$1@dont-email.me>
User-Agent: ForteAgent/8.00.32.1272
MIME-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 8bit
Lines: 108
X-Trace: sv3-mjKWzMxwLYh5tAn5nP8vMk2hayIrNZxtr0w9FKocxDbwWGH+bOHzjKGTuJfsSO0HWop/LoG2xwbxRmM!tKwbNzbnZbDmjz1s0lCo33MLL0xdlCT6nKYXLFjobAN5ekwpSKoPd/JOLZsskCEE9FMi06x3FvRY!/lzqzw==
X-Complaints-To: www.supernews.com/docs/abuse.html
X-DMCA-Complaints-To: www.supernews.com/docs/dmca.html
X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers
X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly
X-Postfilter: 1.3.40
Bytes: 5491

On Fri, 31 May 2024 13:29:02 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:

>On 5/31/24 12:40, john larkin wrote:
>> On Fri, 31 May 2024 00:04:47 -0000 (UTC), Phil Hobbs
>> <pcdhSpamMeSenseless@electrooptical.net> wrote:
>> 
>>> john larkin <jl@650pot.com> wrote:
>>>> On Thu, 30 May 2024 21:46:20 -0000 (UTC), Phil Hobbs
>>>> <pcdhSpamMeSenseless@electrooptical.net> wrote:
>>>>
>>>>> john larkin <jl@650pot.com> wrote:
>>>>>> On Thu, 30 May 2024 11:03:19 GMT, Glen Walpert <nospam@null.void>
>>>>>> wrote:
>>>>>>
>>>>>>> On Thu, 30 May 2024 09:14:58 -0000 (UTC), Cursitor Doom wrote:
>>>>>>>
>>>>>>>> On Thu, 30 May 2024 15:45:21 +1000, Bill Sloman wrote:
>>>>>>>>
>>>>>>>>> On 30/05/2024 3:37 am, john larkin wrote:
>>>>>>>>>> On Wed, 29 May 2024 17:12:21 -0000 (UTC), Cursitor Doom
>>>>>>>>>> <cd999666@notformail.com> wrote:
>>>>>>>>>>
>>>>>>>>>>> On Wed, 29 May 2024 13:52:34 +1000, Bill Sloman wrote:
>>>>>>>>>>>
>>>>>>>>>>>> Yttrium iron garnet tuned oscillators were around back then, but
>>>>>>>>>>>> their 2GHz to 8GHz range was too high for me to count with the
>>>>>>>>>>>> integrated circuits around then - we had to go the Gigabit Logic's
>>>>>>>>>>>> GaAs parts to get to 800MHz, and that became the unique selling
>>>>>>>>>>>> point of the system.
>>>>>>>>>>>
>>>>>>>>>>> YIG oscillators were quite the thing back in the day, but I'm
>>>>>>>>>>> guessing they've been completely superseded by now to get to ever
>>>>>>>>>>> higher frequencies. Seems we've gone from -
>>>>>>>>>
>>>>>>>>> This misses Jan Panteltje's thread "Small magnetic tunable filter for
>>>>>>>>> 6G and beyond" which is about Yig being used today.
>>>>>>>>
>>>>>>>> That article makes it seem like YIG is some revolutionary, new, emerging
>>>>>>>> technology!
>>>>>>>
>>>>>>> Use of YIG filters as a replacement for varactor tuning could turn out to
>>>>>>> be significant.  2022 Microwave Journal article:
>>>>>>>
>>>>>>> <https://www.microwavejournal.com/articles/37980-reinventing-yig-
>>>>>>> technology-for-microwave-filter-applications>
>>>>>>
>>>>>> The VIDA oscillators still look like giant expensive power hogs. They
>>>>>> don't specify modulation bandwidth on the data sheets that I see, but
>>>>>> it must be terrible.
>>>>>>
>>>>>> One can't modulate a hundreds-of-mA electromagnet very fast.
>>>>>>
>>>>>> An LC osc with a varicap is a more sensible VCO. Narrowband, one can
>>>>>> varicap a coaxial ceramic resonator, or a PCB ring oscillator, or
>>>>>> something. Cheap and fast.
>>>>>
>>>>> And far, far noisier than the best YIGs.
>>>>
>>>> Coaxial ceramic resonators have Qs in the thousands, and low tempcos.
>>>>
>>>>
>>> If you can find one at the exact frequency you need.  YIGs have a huge
>>> tuning range.
>>>
>>> IIRC you also said that they’re piezoelectric.
>> 
>> The CCRs are high-K, usually shorted, transmission lines, not
>> piezoelectric. Prop delay is a tiny fraction of c. You can TDR them as
>> such. Z is usually in the 10 ohm ballpark.
>> 
>>>
>>> I’m not saying that YIG is the answer to everything, but for some things
>>> it’s amazing and (AFAIK) unique.
>> 
>> No argument, but they will always be big and expensive slow-tuning
>> power hogs, which is fine in a spectrum analyzer.
>> 
>> RF synthesizer chips are pretty amazing these days too. They make a
>> pretty good first LO too, but they are small and cheap.
>> 
>>>
>>> Sure improves spectrum analyzers!
>> 
>> I wonder if the latest SAs use YIGs.
>> 
>> 
>>>
>>> Cheers
>>>
>>> Phil Hobbs
>
>I gather many spectrum analyzers these days mix successive
>slices of the spectrum down to where an ADC can acquire the
>whole slice, and the remaining processing is all software FTs.
>
>No need for YIG oscillators, and the LO synthesizer needs
>only coarse steps.
>
>Jeroen Belleman

Yes, digital IF.

The price of a several-GHZ sa has dropped by over 10:1 in the last 20
years, mostly from using a lot of digital stuff.

You can get an impressive 8 GHz RF synth chip for about $5 now.