From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io1-xd31.google.com (mail-io1-xd31.google.com [IPv6:2607:f8b0:4864:20::d31]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 2B8613B2A4 for ; Mon, 14 Jun 2021 15:09:31 -0400 (EDT) Received: by mail-io1-xd31.google.com with SMTP id h5so4079264iok.5 for ; Mon, 14 Jun 2021 12:09:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nathan.io; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=HSSKR4iWphTzbgWDfd8oxo2/vbEyCuXMOOU9FTPJiQw=; b=CD9nVgFlaT8EXUDpLEnrc13DuVhiHKowAM3XsVqFo00OPPo60hr72gOfNgIb/2ZF2Y 9s0f5r+xRFmq4Z42ssIjFLh4xvkQF4ibx4Tr2OkqX8W2/U2fQliNg2txSzfj7M+GTcRL s+pX0fRT2HeFjIVeb7muoGdJkjYsV5augULycGiFJd58ktJYCh4bS0Zb0k94Tb511M2r ZrzRZP4gQHn6W7SdBUDzegQHE3Q+saLT3IsVAn/qQYVm10S4kwv+3kt9nI9W5SnZacxS jnKmHXNXVgEVNjiewTHUed0/siEPMgHP6hx9fxTobgDbFLWgbpGRaA/BqiT8dYhpz5ZV sw/w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=HSSKR4iWphTzbgWDfd8oxo2/vbEyCuXMOOU9FTPJiQw=; b=p6Zz0cRlDiiGDrAMixUahMzuxrgH6J2vavZDFOdENHKWSQDh2fBezyXLXbevg/Qr8r TKvX3t3Ht5dwFfSVKpMl71MiQaf8FKW14CXwErcaBTPYkFaCzVa2DZ/jVOgSY4F+lPhA J25ioJsEdVPnGuxOZDtbClvXliF7fXRwEWxb9OMhQt4xMT47BHKXaN7jyqm2O3m8gytp qOFtGpZ6Sp4d+02MQmXK0VaMTpcPyxTqjOCXkGlFJPeLNCKJ2XNoAcMgTK/PbdevqzDC QhTU5qWV0mh64wjK2xU9Y3fdNr8mHjnzVAzZYRxqdJudFbnBzAjsmHGl6dGdeEfELP6L OICA== X-Gm-Message-State: AOAM532gsWpfF2D4iGkvzY4JGcxF4Dm+zkYO3J4IN5oX3khFV13dsSyi TSuOwltlhty/I6hrIxD7btOLaNslFuDMrnt3TzLvym+VnIDGBA== X-Google-Smtp-Source: ABdhPJxIfztIAQtTCCezmBInBU+cGrr6QFk5ujvSKRhNgkS9o6WiEpoaFcWwb6zTcv3C7ytyqQbYvjQ9YFLdRrDCGJo= X-Received: by 2002:a02:a710:: with SMTP id k16mr18326882jam.46.1623697770384; Mon, 14 Jun 2021 12:09:30 -0700 (PDT) MIME-Version: 1.0 References: <20210614120705.31634f9a@spidey.rellim.com> In-Reply-To: <20210614120705.31634f9a@spidey.rellim.com> From: Nathan Owens Date: Mon, 14 Jun 2021 12:09:19 -0700 Message-ID: To: "Gary E. Miller" Cc: starlink@lists.bufferbloat.net Content-Type: multipart/alternative; boundary="000000000000d3a8f605c4be980b" Subject: Re: [Starlink] GPS Dongle? X-BeenThere: starlink@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Starlink has bufferbloat. Bad." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 14 Jun 2021 19:09:31 -0000 --000000000000d3a8f605c4be980b Content-Type: text/plain; charset="UTF-8" Thanks for the info Gary! Why wouldn't you recommend the hat? Anything you'd recommend that is actually purchasable? I can't seem to find any of the Navisys units, and ideally non-USB would be better? On Mon, Jun 14, 2021 at 12:07 PM Gary E. Miller wrote: > Yo Nathan! > > On Mon, 14 Jun 2021 10:40:36 -0700 > Nathan Owens wrote: > > > Sorry, it was MACx-1, but either way, I decided to go for an Adafruit > > Raspberry Pi GPS "Hat", which does 1PPS. > > I do not recommend that HAT. There are much better ones available at > similar prices. > > > I'll setup a raspberry pi > > with RT_PREEMPT > > RT_PREEMPT is overkill. The best you can get on a RasPi is about 54ns > accuracy. Due to the clock granularity of 54ns. > > > and run as a Stratum-1 Clock locally. > > But always have other chimers in your configuration file. > > > This should > > help with better irtt timings. This can be done for <$100 if anyone > > else wants super accurate time. > > For some definition of "super". > > > > Does anyone know if any MAC1-X GPS dongles or anything similar are > > > available anywhere? > > They pop up now and then. Right now GPS parts are hard to find, much > less at good prices. Search for Navisys GR-601W, GR-701W, or GR-801W. > The "W" suffix says it outputs PPS. > > The MAC1-X, or any PPS over USB, will only get you to > 1 milli second > because of the USB. > > RGDS > GARY > --------------------------------------------------------------------------- > Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703 > gem@rellim.com Tel:+1 541 382 8588 > > Veritas liberabit vos. -- Quid est veritas? > "If you can't measure it, you can't improve it." - Lord Kelvin > _______________________________________________ > Starlink mailing list > Starlink@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/starlink > --000000000000d3a8f605c4be980b Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Thanks for the info Gary!

Why would= n't you recommend the hat? Anything you'd recommend that is actuall= y purchasable? I can't seem to find any of the Navisys units, and ideal= ly non-USB would be better?

=
On Mon, Jun 14, 2021 at 12:07 PM Gary= E. Miller <gem@rellim.com> wro= te:
Yo Nathan!
On Mon, 14 Jun 2021 10:40:36 -0700
Nathan Owens <nath= an@nathan.io> wrote:

> Sorry, it was MACx-1, but either way, I decided to go for an Adafruit<= br> > Raspberry Pi GPS "Hat", which does 1PPS.

I do not recommend that HAT.=C2=A0 There are much better ones available at<= br> similar prices.=C2=A0

> I'll setup a raspberry pi
> with RT_PREEMPT

RT_PREEMPT is overkill.=C2=A0 The best you can get on a RasPi is about 54ns=
accuracy.=C2=A0 Due to the clock granularity of 54ns.

> and run as a Stratum-1 Clock locally.

But always have other chimers in your configuration file.

> This should
> help with better irtt timings. This can be done for <$100 if anyone=
> else wants super accurate time.

For some definition of "super".

> > Does anyone know if any MAC1-X GPS dongles or anything similar ar= e
> > available anywhere?

They pop up now and then.=C2=A0 Right now GPS parts are hard to find, much<= br> less at good prices.=C2=A0 Search for Navisys GR-601W, GR-701W, or GR-801W.=
The "W" suffix says it outputs PPS.

The MAC1-X, or any PPS over USB, will only get you to > 1 milli second because of the USB.

RGDS
GARY
---------------------------------------------------------------------------=
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
=C2=A0 =C2=A0 =C2=A0 =C2=A0 gem@rellim.com=C2=A0 Tel:+1 541 382 8588

=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 Veritas liberabit vos. -- Quid es= t veritas?
=C2=A0 =C2=A0 "If you can't measure it, you can't improve it.&= quot; - Lord Kelvin
_______________________________________________
Starlink mailing list
Starlin= k@lists.bufferbloat.net
https://lists.bufferbloat.net/listinfo/starlink
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