[time-nuts] DMTD Question
EWKehren at aol.com
EWKehren at aol.com
Mon Jan 25 14:11:13 UTC 2010
Going from 10 boards to 100 will reduce board cost by about 10%. Depending
of the final version the qty. 10 cost will be either $ 29 or 36. That
is for mixer and counter board. Take out $9 if you will not use the counter.
Bert
In a message dated 1/25/2010 8:44:29 A.M. Eastern Standard Time,
david.partridge at dsl.pipex.com writes:
Translation: FWIW == For What It's Worth
So, one hundred boards will probably cost only a little more than ten
boards.
Dave
-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of EWKehren at aol.com
Sent: 25 January 2010 13:27
To: time-nuts at febo.com
Subject: Re: [time-nuts] DMTD Question
I am not familiar with FWIW 100. Tell me more. Thanks Bert Kehren
In a message dated 1/25/2010 8:22:30 A.M. Eastern Standard Time,
david.partridge at dsl.pipex.com writes:
FWIW 100 boards will likely cost not a great deal more (say $5-20
depending
on board size than ten.
Dave
-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of EWKehren at aol.com
Sent: 25 January 2010 12:01
To: time-nuts at febo.com
Subject: [time-nuts] DMTD Question
Allow me to add some comments to this subject.
Five month ago I set out to make a DMTD that would be $ 200 max and be
such
that any one can build it with readily available parts. The unit also
includes five counters yielding a resolution of 1 E-15. Using five
counters not only gives Allan Variance but also frequency difference.
The
counter is powered by the computer through USB and also transfers the
data
to the PC.
The counter section is less than $30 of the total cost. The cost goal
has
been reached. The counter does not have to be used if one wants to use
his
present counter. The DM board does have high speed opto couplers that
allow other counters. Corby is presently using that approach. Cost does
not include the offset Osc. but a low cost solution is in the works,
subject to evaluation.
Corby Dawson and Richard McCorkle have been major contributors.
The goal is 1 E-13 and present tests show 3 E-13 right out of the box.
Having Cesiums, Rubidiums and Xtal Osc. the best I have is a FTS 1000
A-100
with 3.11 E-13 at one second. I also think I will never have any thing
better than the FTS unit. That is why my goal is 1 E-13.
The present unit uses SYPD-1 as mixers but Corby will test the unit
with a
couple of HP10514A's to evaluate the Mixer contribution.
I realize I am offending some of the purists on this site but I wanted to
keep cost down so I squeezed both channels on a very compact board
(4.3X2.9) and the counter is on a 4.3X2.3 board. How ever if we will not
reach 1
E-13 with this approach I have a fallback using individual boards for
each
channel still meeting the cost goal. Other Mixers will also be evaluated,
like the SRA1 since price and availability of the HP10514A/B will not
help
the cost goal.
1 E-13 should satisfy 95% of time-nuts and at $200 including PC boards.
The second board with some changes hopefully will be assembled this week
for testing and based on its results a third board will go to
ExpressPCB.
It is moving slower than what I had hoped for, but 3 E-13 right out of the
box with no special magnetic shielding or power supply decoupling gives me
hope.
PC boards will be the major cost factor, for my calculations I assume in
my
calculations that ten boards will be ordered at a time.
Bert Kehren Miami
_______________________________________________
time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
More information about the time-nuts
mailing list