[time-nuts] LPRO-101 BITE (~lock) Signal Always Low
Bob Camp
kb8tq at n1k.org
Tue Mar 22 22:23:31 UTC 2016
Hi
I’ve always found that pin 9 (EFC monitor) gave you a pretty good idea of the lock status.
Bob
> On Mar 22, 2016, at 8:43 AM, Wayne (gmail) <wayne.holder at gmail.com> wrote:
>
> The BITE signal is the only way to to know if it has a lock...
>
> Wayne
>
>> On Mar 22, 2016, at 4:37 AM, Bob Camp <kb8tq at n1k.org> wrote:
>>
>> Hi
>>
>> There are probably a dozen or more things that contribute to the BITE output. It could be
>> a regulator out of range. It also could be the VCXO nearing tune limit. If the unit locks up and
>> seems to work, I’d ignore it and move on.
>>
>> Bob
>>
>>> On Mar 21, 2016, at 9:42 PM, Wayne Holder <wayne.holder at gmail.com> wrote:
>>>
>>> I have a surplus LPRO-101 that seems to power up OK. The power draw starts
>>> at 1.7 Amps and then, after a few minutes, drops down to 600 mA, or so and,
>>> after this startup, the output shows a 10.000 MHz signal thats 's
>>> accurately as I can measure it. The lamp voltage is 6.2 volts, which seems
>>> within spec. However, the BITE signal that's supposed to indicate lock
>>> with a LOW level is always LOW and never changes. The docs say that BITE
>>> signal should start at a HIGH level to indicate no lock and then drop to a
>>> LOW when lock is obtained. So, this behavior seems all wrong.
>>>
>>> I opened the case and observed the purple glow of the lamp and probed
>>> around IC U401, which buffers the BITE signal, and saw the same signal LOW
>>> level. U401 is getting 5 volt power and the inputs to the AND gate used as
>>> a buffer for the BITE signal match what I'd expect. But, lacking a proper
>>> schematic, I'm not sure how to trace this back to the problem. Has anyone
>>> ever seen a symptom like this with an LPRO101?
>>>
>>> Wayne
>>> _______________________________________________
>>> 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_lists.febo.com
mailing list