[time-nuts] Brooks Shera GPSDO

[glen english LIST]

Larry, Take a look at Brooks Shera's article in QST. you might know of it.

In my opinion, this has been the 'best ever' description of rolling your 
own.

The July, 1998 issueBrooks Shera, W5OJM, titled, "A GPS-Based Frequency 
Standard. <https://www.qsl.net/n9zia/wireless/QST_GPS.pdf>"

https://www.qsl.net/n9zia/wireless/QST_GPS.pdf

I build several of these and they made "good" GPSDOs

much has been written about this, and emulating it for other hardware.

https://k6jca.blogspot.com/2018/12/simulating-brooks-shera-w5ojm-gpsdo.html

https://github.com/k6jca/Brooks-Shera-GPSDO

u can still buy the original PCB PCB

http://www.a-aengineering.com/gps.htm


On 20/02/2022 10:59 am, Larry Gadallah wrote:
> After poring over the several valuable references people have posted
> here, it seems that even the common commercial GPSDOs have
> implementation problems, so it seems like there's no (financially
> viable) off the shelf solution.
>
> It would indeed be convenient to have a kit option, but I'd image the
> potential marked for a GPSDO kit is vanishingly small.
>
> FWIW, I started with a VE2ZAZ board and an Isotemp OCXO and a Motorola
> receiver of questionable provenance. Since then I've gathered an HP
> 10811D and I have an HP E1938A coming (I think), so I have only so far
> gathered some essential components that I hope are competent.
>
> On Sat, 19 Feb 2022 at 07:13, Bob kb8tq <kb8tq at n1k.org> wrote:
>> Hi
>>
>> Building a kit is very different than a from scratch design. A
>> Heathkit (to extend the years ago ham radio analogy) radio
>> was an option when you shopped for your Drake. Building it
>> would give you some experience.
>>
>> The Heathkit *design* was done for you and all the complicated
>> higher level stuff was worked out / tested out / reworked / retested
>> by somebody else. As long as you put it together correctly, it
>> worked and was a good radio.
>>
>> These days there aren’t a lot of folks selling kit GPSDO’s. Even
>> the kit radio business isn’t what it once was. “I’m going to do
>> a GPSDO” these days generally means a scratch design.
>>
>> Bob
>>
>>> On Feb 19, 2022, at 2:41 AM, Bill Beam <wbeam at gci.net> wrote:
>>>
>>> But there is a magazine article....
>>> <https://www.qsl.net/n9zia/wireless/QST_GPS.pdf>
>>> By Brooks Shera, W5OJM.  QST July, 1998.
>>>
>>> Following this article I built my unit in 1998 using his PCB and a Motorola UT+.
>>> It has been running almost continuously since then - almost 25 years.
>>> It has been thru several HP 10811 and 10844 oscillators during that time.
>>>
>>> Even though Brooks is SK his GPSDO is still running.
>>>
>>> Regards.
>>> Bill, NL7F

-- 
Glen English
RF Communications and Electronics Engineer

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