Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low...

[Oz-in-DFW]

On 3/23/2016 11:45 AM, Burt I. Weiner wrote:
> Would someone please tell me what "BITE" signal is.
>
> Thanks,
>
> Burt, K6OQK
>
> >Hi
> >
> >Which strongly suggests that the BITE line is telling the truth. The
> unit is
> not in lock
BITE = Built In Test Equipment

It's used to describe internal features designed to indicate the
operation of the unit in which they are incorporated.  Milspeak for
self-test, but implying more (usually far more) than a cursory test.

-- 
mailto:o...@ozindfw.net
Oz
POB 93167 
Southlake, TX 76092 (Near DFW Airport) 



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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

Wayne,

I suggest another test too, but this requires a bit of luck.
Power up the unit, and wait until it warms up, say 5 minutes. The VCXO voltage 
will stuck at 14.5V. Then power down the unit in order to restart the sweep 
cycle, just enough, say one second, then power up. If you are lucky and the 
VCXO voltage at lock would be greater than your 7.2V, you will get a lock. As 
your BITE signal is always low, you could notice the lock just looking at pin 
9, which will not reach 14.5V. This worked for me, but will not work if the 
VCXO voltage at lock would be less than your 7.2V.

Antonio I8IOV

>Hi
>
>Which strongly suggests that the BITE line is telling the truth. The unit is 
not in lock
>and it’s broke. If you have the gear, you can verify this by running the tune 
input up and
>down and seeing if the output varies by about 0.02 Hz or not. 
>
>Bob
>
>> On Mar 22, 2016, at 11:36 PM, Wayne Holder  wrote:
>> 
>> The signal on pin 9 starts at about 7.2 volts then slowly increments up to
>> 14.5 volts over a period of about 138 seconds.  It then seems to stay stuck
>> at 14.5 volts and only repeats the cycle if I power down,w wait and then
>> power back on.
>> 
>> Wayne

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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[Bob Camp]

Hi

Which strongly suggests that the BITE line is telling the truth. The unit is 
not in lock
and it’s broke. If you have the gear, you can verify this by running the tune 
input up and
down and seeing if the output varies by about 0.02 Hz or not. 

Bob

> On Mar 22, 2016, at 11:36 PM, Wayne Holder  wrote:
> 
> The signal on pin 9 starts at about 7.2 volts then slowly increments up to
> 14.5 volts over a period of about 138 seconds.  It then seems to stay stuck
> at 14.5 volts and only repeats the cycle if I power down,w wait and then
> power back on.
> 
> Wayne
> 
> On Tue, Mar 22, 2016 at 3:23 PM, Bob Camp  wrote:
> 
>> 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) 
>> 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  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 
>> 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
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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

Hey Wayne,
I said "you should read more than 1 Mohm", but if R215 is interrupted, of 
course.
Antonio





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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

>From: Hal Murray 
>
>iovane wrote:
>> are you sure your LPRO actually locks? You say you have measured 10.000 MHz
>> but you don't mention the other decimals. Some years ago I characterized
>> some  LPROs of mine, and from my notebook I take that, on one sample for
>> instance,  prior to lock the frequency swept up and down between (about)
>> 9.999860 and  10.000230.

>How long does it take to do a sweep cycle?
>
>If your gear is averaging over a longer time to get a more accurate 
frequency 
>value, will it give you the average frequency?

A sweep cycle lasts in the order of the minute. Typically the LPRO locks in 
about 3.5 minutes. I used gate time of 0.1 and 1 second on a 9 digit counter.

Antonio I8IOV

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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[Bob Camp]

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)  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  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  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@febo.com
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>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>> and follow the instructions there.
>> 
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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[Wayne Holder]

I don't currently have a way to accurately measure the frequency of the
output, but my assumption is that oscillator is running, but not locked.  I
did some more poking around and found that the crystal volts monitor (pin
9) starts low (around 4 volts) and then slowly rises as the unit runs.  It
rises to about 14 volts and then stops.  So, this may be a similar problem
to what you described.  However, lacking proper schematics, I'm not sure
where to look next.

Wayne

On Tue, Mar 22, 2016 at 8:43 AM, iovane--- via time-nuts  wrote:

> Wayne,
>
> are you sure your LPRO actually locks? You say you have measured 10.000 MHz
> but you don't mention the other decimals. Some years ago I characterized
> some
> LPROs of mine, and from my notebook I take that, on one sample for
> instance,
> prior to lock the frequency swept up and down between (about) 9.999860 and
> 10.000230. Such a span was rather typical among units. A faulty unit of
> mine
> remained stuck at the upper limit without reversing the sweep. This was
> due to
> a faulty resistor in one of the two (upper) voltage comparator circuits.
> Anyway
> I don't know if this would affect the BITE, but I suggest you to check the
> other decimals.
>
> Antonio I8IOV
>
> >
> >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  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 
> 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
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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

Perfect !!
The swept voltage should not reach 14V, but only about 12.5V and then reverse. 
Your upper comparator is faulty. Check resistor R215 on the PCB bottom face, 
100K SMD. You could chech it on board, and probably you will read more than 1 
Mohm. I bet the trouble is there. R215 is near the longer slot and is of the 
smallest size.
Antonio I8IOV



From: Wayne Holder 


I don't currently have a way to accurately measure the frequency of the output, 
but my assumption is that oscillator is running, but not locked.  I did some 
more poking around and found that the crystal volts monitor (pin 9) starts low 
(around 4 volts) and then slowly rises as the unit runs.  It rises to about 14 
volts and then stops.  So, this may be a similar problem to what you described. 
 However, lacking proper schematics, I'm not sure where to look next.
Wayne
On Tue, Mar 22, 2016 at 8:43 AM, iovane--- via time-nuts  
wrote:
Wayne,



are you sure your LPRO actually locks? You say you have measured 10.000 MHz

but you don't mention the other decimals. Some years ago I characterized some

LPROs of mine, and from my notebook I take that, on one sample for instance,

prior to lock the frequency swept up and down between (about) 9.999860 and

10.000230. Such a span was rather typical among units. A faulty unit of mine

remained stuck at the upper limit without reversing the sweep. This was due to

a faulty resistor in one of the two (upper) voltage comparator circuits. Anyway

I don't know if this would affect the BITE, but I suggest you to check the

other decimals.



Antonio I8IOV



>

>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  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  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

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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[John Ackermann N8UR]

There's a plot of the unlocked sweep of an FE-5690 at the bottom of
http://febo.com/pages/oscillators/rubes/

I think the LPRO is pretty similar.

John

On 3/22/2016 2:02 PM, Hal Murray wrote:


time-nuts@febo.com said:

are you sure your LPRO actually locks? You say you have measured 10.000 MHz
but you don't mention the other decimals. Some years ago I characterized
some  LPROs of mine, and from my notebook I take that, on one sample for
instance,  prior to lock the frequency swept up and down between (about)
9.999860 and  10.000230.


How long does it take to do a sweep cycle?

If your gear is averaging over a longer time to get a more accurate frequency
value, will it give you the average frequency?



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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[Luca Dal Passo]

Hi,
you can check the behaviour of the XTAL V MON voltage to get some
useful information.
It should move up and down during the searching of a lock, and then it
should stop at a certain value when lock is achieved.
Bye
Luca
iw2lje

Il martedì 22 marzo 2016, Wayne (gmail)  ha scritto:

> 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 >
> 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  > 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@febo.com 
> >> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> >> and follow the instructions there.
> >
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> > time-nuts mailing list -- time-nuts@febo.com 
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> > and follow the instructions there.
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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[Hal Murray]

time-nuts@febo.com said:
> are you sure your LPRO actually locks? You say you have measured 10.000 MHz
> but you don't mention the other decimals. Some years ago I characterized
> some  LPROs of mine, and from my notebook I take that, on one sample for
> instance,  prior to lock the frequency swept up and down between (about)
> 9.999860 and  10.000230.

How long does it take to do a sweep cycle?

If your gear is averaging over a longer time to get a more accurate frequency 
value, will it give you the average frequency?


-- 
These are my opinions.  I hate spam.



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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

Wayne,

are you sure your LPRO actually locks? You say you have measured 10.000 MHz 
but you don't mention the other decimals. Some years ago I characterized some 
LPROs of mine, and from my notebook I take that, on one sample for instance, 
prior to lock the frequency swept up and down between (about) 9.999860 and 
10.000230. Such a span was rather typical among units. A faulty unit of mine 
remained stuck at the upper limit without reversing the sweep. This was due to 
a faulty resistor in one of the two (upper) voltage comparator circuits. Anyway 
I don't know if this would affect the BITE, but I suggest you to check the 
other decimals.

Antonio I8IOV 

>
>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  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  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
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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[Wayne (gmail)]

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  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  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
>> ___
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> 
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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[Bob Camp]

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  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
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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

>Da: Tom Miller 
>
>- Original Message - 
>From: "Wayne Holder" 
>
>
>>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 
>>...
>> 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
>
>Does it need a pull up resistor?

No pull-up resistor required, it should work.

Antonio I8IOV
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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[Tom Miller]

- Original Message - 
From: "Wayne Holder" 
To: "Discussion of precise time and frequency measurement" 


Sent: Monday, March 21, 2016 9:42 PM
Subject: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low



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
___


Does it need a pull up resistor?


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