From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-il1-x136.google.com (mail-il1-x136.google.com [IPv6:2607:f8b0:4864:20::136]) (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 10C023B2A4 for ; Mon, 14 Jun 2021 15:14:07 -0400 (EDT) Received: by mail-il1-x136.google.com with SMTP id d1so13138690ils.5 for ; Mon, 14 Jun 2021 12:14:07 -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=9/xuQ0z4RXBwqDTqUC1ZJ8AFAeoB+K5lFXV5Taf/08s=; b=q05QquMgehBLFpe8x2AUxLE2iVzudV2xCxAboUnX0xGAk19947b706UaLTfmd2vKRS vDU0mmwWIL5SlJ6+pGjgHiheZS6g00cv3JTIBtbVkMTMFTZTTFaWpt4qcXye62jQEUNN +M/NeqmfGOrL+nR98uAfaxgKjcYzgivf6lGQwOlf8beMiOryiOCBtA5ZEpBJ3zCZnVkC OVraXPoRH4n5Oay02jUHfxkN9Oh5UocP/UY0wWoreeKmrCyNVyaB1Dc4RZ/SzZK9h6Q3 myany60ppFHBq62HBoGd9S2C0lm7JYHvMoh/Zlicabd6kBMuf6hcFxumXnqR7tU+mx99 3FJg== 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=9/xuQ0z4RXBwqDTqUC1ZJ8AFAeoB+K5lFXV5Taf/08s=; b=SMgOV6/8nNF+MCFx1CZ4SlMggzcC32juTePMVGzTs4LcXobituN4cHzgj9gZmKPD36 ZFF9wQyh3NeSc37nmHfgS5lOnsNJSO1ZOrMnIVF1LdAqJJ5S6aoHRuFNbnvS0xuSO1a3 MWA+ELx/oNrqVQPQDgof67YvaPDzzb393f7uw5fmHwNu9z8ZT6DPRy/O9DtYW8ISjyBp v2IbdTwsReN1vp5EPxDm4IWH8VTtVTG9p1rhadyutZB7jnzhCfvOq2lr0L10R2v+UDoG 6Vduu/pv3rJIuS0T7brQgOTQt/+C1bmTq5+kLpa4oRLJrcAkAd88TEAYt3jDuqOgZeMs OA3Q== X-Gm-Message-State: AOAM5339c6U9aqjSRb+7RMs/ZfXmm+XEKnWuGqc6OytesLU6cu5lydvo tVGRA3C0q6EOkCsP+GoLP9G2HxSEHSk3XCU1CNOFMTS+tzexnAQM X-Google-Smtp-Source: ABdhPJxY2Tiku028wkhM5byXCU7AqMFacz6DxX+OcdZi6yEjxm0PKw56lIyLgzldCWl4oIST/zEAVPWKTqxLt1aJRk0= X-Received: by 2002:a92:c7d0:: with SMTP id g16mr14938109ilk.194.1623698046270; Mon, 14 Jun 2021 12:14:06 -0700 (PDT) MIME-Version: 1.0 References: <20210614120705.31634f9a@spidey.rellim.com> In-Reply-To: From: Nathan Owens Date: Mon, 14 Jun 2021 12:13:55 -0700 Message-ID: To: "Gary E. Miller" Cc: starlink@lists.bufferbloat.net Content-Type: multipart/alternative; boundary="000000000000455b0b05c4bea93c" 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 19:14:07 -0000 --000000000000455b0b05c4bea93c Content-Type: text/plain; charset="UTF-8" I am able to buy the same chip, the uBlox M8Q as hat: https://www.amazon.com/MAX-M8Q-Raspberry-Multi-Constellation-Receiver-Support/dp/B08HJFYPGX/ On Mon, Jun 14, 2021 at 12:09 PM Nathan Owens wrote: > 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 >> > --000000000000455b0b05c4bea93c Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
On Mon, Jun 14, 2021 at 12:0= 9 PM Nathan Owens <nathan@nathan.io<= /a>> wrote:
<= div dir=3D"ltr">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 ideall= y non-USB would be better?

<= div dir=3D"ltr" class=3D"gmail_attr">On Mon, Jun 14, 2021 at 12:07 PM Gary = E. Miller <gem@relli= m.com> wrote:
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
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Starlink mailing list
Starlin= k@lists.bufferbloat.net
https://lists.bufferbloat.net/listinfo/starlink
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