FRK is possible candidate we are looking at it add filter, reduce time constant
Corby did but forgot to reduce filter time constant. 5065A is 0.05 seconds.
We have to many projects low on the list Juerg is right now doing the new A9
for Corby
If any body wants to seriously get involved contact
Perrier,
The telecom Rubidiums don't leave much meat on the bone for improvements
as they sacrificed pretty much everything else to be cheap, small, and
low power consumption.
Most of these tradeoffs work directly against trying to get better short
term stability out of them.
Bummer.
Cheers,
C
List,
I've been following the ongoing mod process for the HP 5065A super on the list.
Two questions:
1. Are any of these upgrades applicable to the Lucnet and other Rb units?
2. Are there any other Rb units available (that don't cost you your first born
child IF they can be found) that could be f
In message <2a6c14a0-823a-4177-aefd-bed8bcea8...@n1k.org>, Bob kb8tq writes:
>It turns out that the nickel’s really awful magnetic properties at RF [...]
The semiconductor industry has serious problems with electromigration of
very tiny copper conductors.
A large company in the business
Hi
> On Feb 23, 2018, at 6:17 PM, jimlux wrote:
>
> On 2/23/18 1:33 PM, Bob kb8tq wrote:
>> Hi
>>> On Feb 23, 2018, at 4:23 PM, Attila Kinali wrote:
>>>
>>> Hoi Bob,
>>>
>>> On Thu, 22 Feb 2018 21:58:09 -0500
>>> Bob kb8tq wrote:
>>>
The same nickel plating effect gets into a lot of th
On 2/23/18 1:33 PM, Bob kb8tq wrote:
Hi
On Feb 23, 2018, at 4:23 PM, Attila Kinali wrote:
Hoi Bob,
On Thu, 22 Feb 2018 21:58:09 -0500
Bob kb8tq wrote:
The same nickel plating effect gets into a lot of things. If you are shopping
for very
low IMD connectors, nickel plating is out. Things
On Thu, Feb 22, 2018 at 3:29 PM, Leo Bodnar wrote:
> Here is ENIG fact that is not widely known at the moment but which some might
> find useful.
>
> I could not understand why I get better TDR and insertion loss results from
> solder-mask covered microstrip transmission lines than from otherwis
Hi
> On Feb 23, 2018, at 4:23 PM, Attila Kinali wrote:
>
> Hoi Bob,
>
> On Thu, 22 Feb 2018 21:58:09 -0500
> Bob kb8tq wrote:
>
>> The same nickel plating effect gets into a lot of things. If you are
>> shopping for very
>> low IMD connectors, nickel plating is out. Things get non-linear (t
Hoi Bob,
On Thu, 22 Feb 2018 21:58:09 -0500
Bob kb8tq wrote:
> The same nickel plating effect gets into a lot of things. If you are shopping
> for very
> low IMD connectors, nickel plating is out. Things get non-linear (to a very
> slight
> degree) when it is present. If -180 db is the goal
Keep in mind that soldermask will also change the field distributions
around a
microstrip line, and will somewhat mitigate the microstrip's dispersive
behavior
as well.
I once worked with some miccrostrip couplers at around 2-4 GHz and found
that
directivity was significantly improved by adding tw
Hi
The same nickel plating effect gets into a lot of things. If you are shopping
for very
low IMD connectors, nickel plating is out. Things get non-linear (to a very
slight
degree) when it is present. If -180 db is the goal for those spurs, you might
only
hit -120 db with the nickel connector
On 2/22/18 12:29 PM, Leo Bodnar wrote:
Here is ENIG fact that is not widely known at the moment but which some might
find useful.
I could not understand why I get better TDR and insertion loss results from
solder-mask covered microstrip transmission lines than from otherwise identical
microst
It appears that ENIG gold is extremely thin (2 - 8 microinches),
and if so does not cause a solderability problem.
-- Tom, N5EG
On Thu, Feb 22, 2018 at 3:18 PM, Mark Goldberg
wrote:
> My reading of IPC J-STD-001F Paragraph 4.5 says that the gold embrittlement
> issue does not apply to ENIG or
My reading of IPC J-STD-001F Paragraph 4.5 says that the gold embrittlement
issue does not apply to ENIG or ENEPIG. Paragraph 4.5.1 does say other gold
shall be removed so there won't be solder embrittlement.
Is that still correct?
The issue with ENIG and RF is interesting. I have not heard that
In general it's bad practice to gold plate SMT solder pads. The reason is
that proper SMT soldering utilizes a very small amount of solder and the
gold plating
will partially dissolve into the molten solder. Because of the small amount
of
solder, the percentage of gold will be high enough to embri
Here is ENIG fact that is not widely known at the moment but which some might
find useful.
I could not understand why I get better TDR and insertion loss results from
solder-mask covered microstrip transmission lines than from otherwise identical
microstrips on the same substrate with soldermas
Yes, have the board done with ENIG gold. It typically adds around $15 per run
of boards. I do all my boards with ENIG gold... if for no other reason than
the gold color makes it very easy to determine when your solder paste properly
covers the pads.
And, as Charles mentioned, the quality and
On Thu, 22 Feb 2018 15:33:50 +
"Poul-Henning Kamp" wrote:
> >Then i would go for the LTC6240HV with a +/-5V power supply.
>
> Offset voltage (stability) is a, if not the, *very* important
> parameter for the integrator.
That's another reason to choose the LTC6240 over the LT1793.
Beside the
In message <20180222160256.68d832a88fc2d7da91602...@kinali.ch>, Attila Kinali w
rites:
>Ah.. this looks significantly different than my 5065 service manual shows.
>
>So, I guess you want to build a new board that replaces this?
>
>Then i would go for the LTC6240HV with a +/-5V power suppl
On Thu, 22 Feb 2018 09:24:53 -0500
ew via time-nuts wrote:
> Attached the schematic of the A9 my file of the picture is to large it is the
> integrator.
Ah.. this looks significantly different than my 5065 service manual shows.
So, I guess you want to build a new board that replaces this?
The
Hi
The control loop (of which A9 is a part) ultimately locks the OCXO in the 5065
to the Rb
transition. Gain in the control loop suppresses the noise of the OCXO, making
it’s ADEV
better than it would have been stand alone.
Ok so far? Bob’s not off the tracks (yet)?
The various processes th
Attached the schematic of the A9 my file of the picture is to large it is the
integrator. I just gave Corby my extra A12 RVFR that at one time I was going
to do something along the way you suggested but age and the number of projects
on our list have ought up with reality. Remember when you vis
Ais the LT1793 the best choice the time constant is 0.05 seconds with a 10
K resistor and 5 uF Capacitor
Bshould we add resistors and decoupling on the + - 15 volt op amp supplies
CGold plating the edge connecter, does any one know a reasonable source,
or is doing it at home an opti
On Thu, 22 Feb 2018 07:00:54 -0500
ew via time-nuts wrote:
> Now a step by step work over, including HP mods for later units like
> replacing the 74196’s in the synthesizer module with 74LS196. May have been
> end of life of the 74196.
With some slight change of the circuit, you should be abl
In December I lucked out buying a HP5065A for a very reasonable price, as is
not tested. Turns out it was not working and I was not able to fix it. Corby to
the rescue. Corby and I have shared many projects over the past, go back over
15 years, as a matter of fact he introduced me to time-nuts.
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