See thats the pointer I need there was just tons of information. Quite nice and the price is right. Regards Paul
On Thu, Feb 13, 2014 at 11:11 AM, Chris Albertson <[email protected] > wrote: > You can buy the chip already on the PCB with supporting circuitry for > less then the price of the chip alone. No need to go with a bare > chip. I think the reason is that the tiny SMT package chips sell in > the millions and only a hob best would use the larger DIP through hole > package. Look at eBay #221326355393 as an example. The 3>71 price > includes shipping. The advantage is __Programming__. When you are > working on something like this you tend to want to re-program the > chips ten times an hour and it s VERY convenient to be able to leave > it plugged into the USB port on your computer. Also for debugger a > continuous stream of data on your computer screen, maybe captured to a > file, gives yo insight to the internals. > > That is the advantage of development with the Arduino vs. a bare chip, > you don't have to pull the chip to re-program it. Yousimply change a > line of code using a text editor and click the "load" icon and a few > seconds later you are running again. It is a very fast development > cycle. > > You don't save either cost or space by using a large DIP chip the SMD > chip soldered to a PCB is about the same cost and size but also comes > with the pull up resisters, voltage regulater, standard 6-pin FTDI > interface and so on. > > On Thu, Feb 13, 2014 at 6:36 AM, paul swed <[email protected]> wrote: > > Lars has done a very good job here and good to see the comments and > > excitement. > > Have to agree with HAL that holdover is far more than a second and I am > in > > a good location with the GPS antenna at 90'. I see my 3801 go into > holdover > > occasionally and its not seconds. > > > > Cheapest tinker 10 Mhz is a Xtal with a varicap diode in circuit to > adjust > > frequency. > > Sub $ 5 I would guess. > > > > I was intrigued by the Arduino also and then went looking for > information. > > Just about drowned in whats out there and pricing for the chip is from 99 > > cents to $5. > > What bootloader X Y or Z. I like the pure chip 28 pin approach and do > > appreciate that this won't be H maser accurate. > > > > Looked at the schematic and would appreciate a more complete picture. > > Lars thats a bit more painful to do because everything has to be explicit > > in the schematic when other may build what you have shared. > > Though I have shared some ugly schematics on time-nuts. Guilty as > charged. > > Regards > > Paul. > > WB8TSL > > > > > > On Thu, Feb 13, 2014 at 3:59 AM, Hal Murray <[email protected]> > wrote: > > > >> > >> [Context is cheap VCXO] > >> > >> > When used inside a GPSDO it only has to "hold over" for one second > until > >> the > >> > next correction. > >> > >> Only if you have a good antenna and/or antenna location. > >> > >> I have several low cost GPS units located in far-from-ideal locations. > >> They > >> work most of the time but often fade out for minutes at a time. > >> > >> [This is a poor setup for using the output of a GPSDO to feed other > >> measuring > >> setups, but it's great for finding corner cases in things like ntpd.] > >> > >> > >> -- > >> These are my opinions. I hate spam. > >> > >> > >> > >> _______________________________________________ > >> time-nuts mailing list -- [email protected] > >> To unsubscribe, go to > >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >> and follow the instructions there. > >> > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > -- > > Chris Albertson > Redondo Beach, California > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
