[time-nuts] Re: Thunderbolts ...

[Dana Whitlow]

My experiences with the T'Bolt have not been entirely satisfactory.  If I
set the loop
lime constant long enough to get a satisfying smoothing of the GPS noise (a
few hundred
seconds), then the thermal sensitivity of the VCXO on the T'Bolt rears its
ugly head and
I see a lot of my HVAC system cycling instead.  The T'Bolt E supposedly has
a double-
oven XO, so I'd like to give that a try.  But my wallet says "whoa"!

According to Bodnar, his units do have some choices in the time constant
setting.
I've been considering ordering a Bodnar just for frequency agility, but
have been
holding off out of concern for the complications of dealing with a foreign
supplier.

Dana




On Tue, Jul 20, 2021 at 12:42 PM John Ackermann <jra at febo.com> wrote:

> The Bodnar GPSDO is great for what it is, and has the great advantages of
> small size, low power consumption, low cost, and frequency agility.  But it
> doesn't have an OCXO so its short term and holdover performance isn't in
> the same league as the T'bolt or Z38whatever boxes.
>
> John
>
> On Jul 20, 2021, 1:11 PM, at 1:11 PM, Bob Darlington <
> rdarlington at gmail.com> wrote:
> >Same.  He probably got 250+ requests in short order.  I'm curious how
> >the
> >Leo Bodnar GPSDOs compare.   I'm considering one of these over a
> >thunderbolt for field use for ham radio EME work.
> >
> >-Bob N3XKB
> >
> >On Tue, Jul 20, 2021 at 10:59 AM Wes <wes at triconet.org> wrote:
> >
> >> I wrote Tom, at the address he gave, on Saturday with a query.  So
> >far, no
> >> reply.
> >>
> >> Wes  N7WS
> >>
> >>   On 7/19/2021 4:59 PM, John Miles wrote:
> >> > If you're looking for a low cost surplus GPSDO, the ones Tom
> >mentioned in
> >> > his post on Saturday are the ones you want.  Not a Thunderbolt-E,
> >and not
> >> > something from the China surplus/e-waste market.
> >> >
> >> > -- john, KE5FX
> >> >
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