Good idea! A user could specify, say 3 satellites, with orbital elements. Without internet access, ?there is no way to change these elements as orbits are corrected though, unless one edits them an recompile¡¯s the code -- Sverre
LA3ZA
http://la3za.blogspot.com
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Another possible feature would be satellite rise and set times if there is room in the mcu for the tables.
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Thanks for publishing this nice project, I'll have to put it on my to-do list! :-)
Karl Jan - LA3FY tor. 30. sep. 2021 kl. 08:04 skrev Sverre Holm < svholm54@...>:
My Arduino GPS Clock is now published. It shows GPS info such as UTC time and locator, also local time with daylight saving for a user-configurable timezone, solar and lunar position and rise/set times, NCDXF beacons in real time and much more. Date and time formats adaptable to most formats in use.?On my blog and on GitHub.?
See?
--
Sverre
LA3ZA
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My Arduino GPS Clock is now published. It shows GPS info such as UTC time and locator, also local time with daylight saving for a user-configurable timezone, solar and lunar position and rise/set times, NCDXF beacons in real time and much more. Date and time formats adaptable to most formats in use.?On my blog and on GitHub.?
See?
--
Sverre
LA3ZA
http://la3za.blogspot.com
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Re: PC Boards for QEX Step Attenuator Available
If you are interested in a board, at $3.00 ppd CONUS, please reply off line [click the ¡°Private¡± button].
The first order is sold out and there is sufficient additional interest for a second order.
I will be making a second order next week.
I expect to receive the second set boards near the end of October.
Dick K9IVB
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PC Boards for QEX Step Attenuator Available
I have ordered a limited batch of boards from JLCPCB for the QEX September/October ?2021 ¡°Miniature SMA Step Attenuator¡± pp 9-21 by Tom Alldred VA7TA.
?
If you are interested in a board, at $3.00 ppd CONUS, please reply off line [click the ¡°Private¡± button].
I expect to receive the boards in the first week of October and will have 8 spare boards available.
If there is sufficient additional interest, I would be willing to make a second order.
?
See attached for some additional info.
?
Dick K9IVB
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Re: 10 MHz Rubidium OCXO frequency standard information
Hi Halden,
I use the AR-60A for the Tektronix DC503-A frequency counter (instead of its 10 MHz oscillator) and use the Datum LPRO-101 for the R&S SME03 RF generator.
-- Cheers Attilio
?
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Re: 10 MHz Rubidium OCXO frequency standard information
Hi Attilio,
That looks consistent with my understanding.? The temperature has to be managed to prevent the unit from damaging itself with its heat.? I wish I had a manual for mine, but that's what I get for buying cheap, surplus equipment.
What's your application?
Cheers,
Halden
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Re: 10 MHz Rubidium OCXO frequency standard information
Hi Halden,
If it can help, here is what the Datum LPRO-101 manual reports about the heatsink:
"A heat sink or mounting base plate is required to keep the baseplate temperature under 70¡ãC. Internal self heating of the LPRO will cause local internal temperatures to exceed DATUM's part derating guidelines when used without a heatsink or forced air. (although the maximum manufacturer's operating temperature ratings will not be exceeded). A heat sink with thermal resistance to ambient of less than 2¡ãC/W is required for ambient of 50¡ãC maximum."
-- Cheers
??? Attilio
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Re: 10 MHz Rubidium OCXO frequency standard information
Hi Halden,
it is also my concern. I probably misunderstood what is written on the manual of the Datum LPRO-101, I have to reread it.
-- Cheers
??? Attilio
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Re: 10 MHz Rubidium OCXO frequency standard information
Hi Attilio,
If I understand correctly, rubidium oscillators aren't sensitive to changes in ambient temperature, and that's why they're so useful.? My concern is components failing due to getting too hot.? I think that's what the heatsink is for.
Cheers,
Halden
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Re: 10 MHz Rubidium OCXO frequency standard information
Hi Halden, thanks for the information, I read in my Datum LPRO-101 manual that a 2 ¡ã C / W heatsink should be placed on its bottom plate. If I understand correctly it should serve to stabilize the temperature better and make it less sensitive to changes in ambient temperature.
-- Cheers
??? Attilio
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Re: 10 MHz Rubidium OCXO frequency standard information
Hi Attilio,
I bought a surplus rubidium oscillator of a different brand.? It takes a few minutes for its initial warm-up before it gives its output signal.? But once it does, that signal's frequency is locked and does not change (as far as I can detect) as it continues to get warmer.? After a half hour, it seems to stabilize temperature.? It's quite hot, but not so hot that I cannot keep my hand on it.? If I put it into a cabinet with other components, I'll include a cooling fan.? I hope this helps.
Cheers
Halden VE7UTS
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Re: 10 MHz Rubidium OCXO frequency standard information
Thanks Erik, I'll try.
-- Cheers
??? Attilio
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Re: 10 MHz Rubidium OCXO frequency standard information
Maybe a good place to ask this question would be the projects group on the eevblog forum:? -- HBTE Files section:? /g/HBTE/filesErik, PD0EK
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10 MHz Rubidium OCXO frequency standard information
Hello to all, I bought used an AR-60A (AccuBeat) and a Datum LPRO (I think it's from Efratom) and they both work. I have no experience with these Rubidium frequency standards and would like clarification regarding the optimal operating temperature, i.e. if they need a heatsink and how large it should be (or how many ¡ã C / W). Currently without the heat sink the temperature rises to about 50 ¡ã C then stabilizes.
Thanks for the attention.
-- Cheers
??? Attilio
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Re: Specan log detector and power regulators
Thanks DuWayne,
This build is going to be dead bug style, but I will doubtless be using the 8307 again.
Is your pcb for the dip package or the smd version?
73 Ellis G7SAI
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Re: Specan log detector and power regulators
Post it in any case, someone else in the future may find it useful.
On Tue, 24 Aug 2021 at 18:50, DuWayne Schmidlkofer < duwayne@...> wrote: I have used the 8307 in several projects, and found it to be an extremely sensitive device.? To get a good noise floor you really should shield the? 8307 stage. I have etched my own double sided boards, or have had them made. If you wish I can send the gerber files for ones I hade made by oshpark.? The separate regulator also goes a long way to reducing any noise from the Arduino which can raise the noise floor. I found that good shielding and layout can lower the noise floor by almost 10 dB.? If you want I can post the Gerber files for a small board with regulator I hade made by OSH Park, files should be OK for most of the other board houses.
--
DuWayne,? KV4QB
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Re: Specan log detector and power regulators
I have used the 8307 in several projects, and found it to be an extremely sensitive device.? To get a good noise floor you really should shield the? 8307 stage. I have etched my own double sided boards, or have had them made. If you wish I can send the gerber files for ones I hade made by oshpark.? The separate regulator also goes a long way to reducing any noise from the Arduino which can raise the noise floor. I found that good shielding and layout can lower the noise floor by almost 10 dB.? If you want I can post the Gerber files for a small board with regulator I hade made by OSH Park, files should be OK for most of the other board houses.
--
DuWayne,? KV4QB
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Re: Specan log detector and power regulators
Thanks Erik, I'll stick with keeping the AD8307 on its own shielded daughterboard.? I have some feedthrough capacitors so I may use some of them to keep as much noise out of the detector.
73 de Ellis G7SAI
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Attilio
DuWayne Schmidlkofer