[evlatests] [Fwd: Failures to Tune, at Q-band]

[Bryan Butler]

this is on the L301, or L302, or both?  at any rate this sounds like a 
good approach at least for now.  we should get hichem involved in the 
discussion.

	-bryan


Ken Sowinski wrote, On 11/29/11 10:17 AM:
> Here is my summary of syntheisizer behavior
>
> If standby is asserted, the thing is really not working.
> It may work again if a new frequency request is sent, or,
> in the extreme case, it may need to be re-booted.
>
> If standby is not asserted it may or not be OK. It might
> be locked on the wrong tooth of the comn, or may not know
> that it is not locked.
>
> The lock indicaotr (M_LOCK and C_LOCK) are pretty reliable
> indicators of transient behavior when re-tuning, but not
> reliable as an indicator of failure to lock.
>
> Using the standby monitor point should flag many cases of broken
> synthesizers while not providing false positives.
>
>
>
> On Mon, 28 Nov 2011, Bryan Butler wrote:
>
>>
>> i had it in my head that we never know if the L302 fails to tune. at
>> least not generally. for instance, if it locks on the wrong tooth of
>> the comb, we never know. i can't say anything about the L301 - nothing
>> is sticking in my RAM on that one.
>>
>> -bryan
>>
>>
>> Rob Long wrote, On 11/28/11 16:34 PM:
>>> Ken is right, L301s either lock or they are (hard) broken. When we see
>>> "tuning failures", do we actually see L302 lock warnings? I can look
>>> into archive data and get a feeling for what the synths are doing (but I
>>> can not see frequency).
>>>
>>> Rob
>>>
>>> Ken Sowinski wrote:
>>>> When this happens it is often the case that the module has given
>>>> up and placed itself in 'standby' mode which means it will do
>>>> nothing until it gets a new command to tune to a different frquency.
>>>> I have no way of knowing whther this happens in every case, but I
>>>> use it as a diagnostic when troubleshooting non-working antennas.
>>>>
>>>> There is a monitor point (obviously enough called 'standby')
>>>> to reflect this state. It could generate an alert which would cause
>>>> flagging for the appropriate IF pair. As a reminder:
>>>> L302-1 -> A0C0 or A1C1
>>>> L302-2 -> B0D0 or B1D1
>>>> L302-3 -> A2C2
>>>> L302-4 -> B2D2