[time-nuts] HP 117/10509a

[J. Forster]

> NO! WOW! If this is true then you just saved me hours of work and lots
> of $$$$ for something that would end up being useless.

It is true. It was discussed a few months ago. I have posted on the
testing repeatedly.

> Will WWVB still be useable for frequency phase comparisons, perhaps by
> long integrating periods?

No. The receivers must be modified or replaced. The mods are non-trivial
in practice.

> I spent a lot of time and effort with LORAN and they just killed it.

t least a year ago.

-John

=====================
>
> Technology just keeps costing me!
>
> Ron
>
> -----Original Message-----
> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
> Behalf Of J. Forster
> Sent: Thursday, July 05, 2012 6:31 AM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] HP 117/10509a
>
> You do know that neither a 117A or a 207 will work when WWVB changes to
> BPSK fairy soon?
>
> -John
>
> ===============
>
>
>> Thanks Charles:
>> I will consider your ideas as they seem to be excellent!
>>
>> I wonder if I could just make the whole unit run off of +24VDC or +12
>> VDC.
>> I need to look at the schematics and see what would be the best way to
>> proceed.
>>
>> I currently do not have an antenna for WWVB and need to get up and
>> running before I do anything with it.
>>
>> If successful, would anyone want information on my conversion? I also
>> have a fluke 207 that needs to be recapped.
>> Thanks,
>> Ron
>>
>>
>> -----Original Message-----
>> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]
> On
>> Behalf Of Charles P. Steinmetz
>> Sent: Wednesday, July 04, 2012 11:10 PM
>> To: Discussion of precise time and frequency measurement
>> Subject: Re: [time-nuts] HP 117/10509a
>>
>> Don wrote:
>>
>>>the fet breakdown voltage has of course got to be high enough.
>>
>> If the nuvistor is used as a common-cathode or common-grid amplifier,
>> you can cascode the fet with a bipolar to extend its drain voltage
>> range.  You will need to come up with an appropriate bias source for
>> the bipolar.  Generally, you would want at least 10-15 volts across
>> the FET channel.
>>
>> Choose an appropriate JFET (transconductance, drain current, and
>> gate-drain voltage similar to the nuvistor at the nuvistor's
>> operating point).  You can add degeneration (source resistance) to
>> lower the FET's transconductance if it is higher than the nuvistor's.
>>
>> Best regards,
>>
>> Charles
>>
>>
>>
>>
>>
>> _______________________________________________
>> 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.
>
>
>