Speaking of long time constant analog loops for oscillator disciplining,
see the attached PIX of the loop filter module from an FE AN/URQ-23.
Also a PIX of the schematic.
It is switch selectable for 1 or 100 Second time constants.
I is also hermetically sealed to prevent leakage effects as it u
Hi,
The -60109 usually does have the very good short term stability at short
Tau but to actually use it you need to go open loop on the 5065A or
5061A/B.
In closed loop the instrument actually drives the stability and pretty
much any 10811 variant will work.
HP knew this and recommended going op
With that offset either the oven set point has changed or there has een a
component value shift in the oscillator circuit.
The easiest way to test is to stick in another 10811 if available.
You could also install one of the original 105 style oscillators if you
have one.
Cheers,
Corby
___
Jared,
You have to be within .25Hz so yes I'd say that's most likely your
problem!
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an
email to time-nuts-le...@lists.febo.com
To unsubscribe, go to and follow
Jared,
There is a non-hermetic electrolytic cap in the A7 (100uf C3) that if it
leaks can "eat" the lead or trace off killing the gain..
Pull the A7 and take a look at that.
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com -- To un
Jared,
A few things to try.
On the bottom of the chassis Connect a scope to A8 pin 9. You should have
a 137Hz (approx) sine wave of around 200mv P-P.
If OK on the bottom of the chassis then connect the scope to A7 TP2 AC
coupled.
In open loop and with the 5Mhz within .1Hz you should see a s
Subject: Passive Maser teardown
Just added "update 5" to http://www.leapsecond.com/maser/
It gives details on "digging down" to the cavity of the Maser.
Cheers!
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an
Hi!
Here is part 2 of the notes for installing HP 5061A/B "mini" tubes into
the 5071A.
Cheers,
Corby
eepromnotesb.docx
Description: MS-Word 2007 document
___
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an
email to time-
Tobias,
To get accurate noise floor at the lower Tau you need to make sure your
delay between each channel is set to as close to zero as possible.
A variable phase shifter or various lengths of cables/connectors will
work.
Cheers,
Corby
___
time-nuts
In reference to:
"It would be cool to say one has a "primary standard", So, I think
we should be careful with the term, it's get thrown around too lightly."
Any of the hobby grade used Cesium standards is actually a Primary
frequency standard as it does meet the definition of:
A frequency s
Working on a project and need the following.
The HP high stability tubes have a pair of violet and violet/white wires
exiting the potting that have the nylon push on connections. These were
for the degaussing connection.
I'm looking for 3 more sets of these wires.
I do have a big pile of dead
Skips data is very nice!
But speaking of dropping into the -14ths, the HP 5065A is hard to beat.
(Unless you are fortunate enough to have an 8607 option 8 sitting in your
lab!)
The Yellow trace on the attached comparison plot is my 5065A, it's a
really excellent performer and drops into the -14th
Walter,
The widget is a module from the FTS 4050 series of Cesium standards.
I have a couple of these modules.
Schematics are in the manuals.
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.f
For some DMTD stuff on EEVBlogForum:
https://www.eevblog.com/forum/metrology/dmtd-board/
https://www.eevblog.com/forum/metrology/dmtd-tutorial/
And lastly,
https://www.eevblog.com/forum/metrology/a-simple-time-interval-counter-fo
r-dmtd-work/
Many Thanks to Tom Van Baak for his help with this
Thanks for the work in keeping this valuable resource up and running!
Much appreciated.
Corby Dawson
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and foll
And here is an EFOS2 Maser glow.
Happy holidays, and Merry Christmas!
Corby___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
The gettering in the tube is only for capturing any stray Cesium atoms
that don't get caught in the main gettering patch. If the gettering fails
or gets too loaded up then the Cesium background level will get too high
causing poor SN.
The ion pump is for any gases.
When a tube is off for extended
Paul,
One other thing to check.
Put a DC coupled scope on the C-field pot wiper and rotate the pot back
and forth.
Make sure there are no jumps or noise.
Sometimes the pot gets noisy in a section.
Rotating it back and forth across the bad sections will usually clean it
up.
Cheers,
Corby
__
Paul,
C-field current is adjustable from 2.5 to 6ma.
I use a clip on milliammeter.
Also you can kludge in an HP 3325A/B in place of the A1 synthesizer to
see if that's the problem.
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.co
Skip,
Nice! Now you can go down another rabbit hole!!!
Nothing fancy is needed for noise floor DMTD tests!
Here is a PIX of what I use.
- A passive SMA power splitter
- a couple short SMA cables
- an assortment of sma M to SMA F adaptors (elbows work nice)
- A variable phase shifter from an HP
Also when you google "alien deviation" you get:
About 11,800,000 results (0.50 seconds)
Cheers! :>)
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
a
The 106D DMTD unit was designed by NBS (now NIST), and the BNC connectors
I mentioned were also isolated from the chassis.
The shield side was bypassed to the chassis ground inside via a 50 Ohm
resistor and a .1uf capacitor.
I retained those when I converted to isolated SMA.
The center pin and shi
Hi,
My NBS 106D DMTD originally had all BNC connectors but after finding out
BNCs are not the best for DMTD units I retrofitted it with insulated SMA
connectors.
I used nylon washers on both sides. See PIX.
Cheers,
Corby___
time-nuts mailing list -- ti
If the unit fails again just diconnect the 60Mhz output jack from A3 and
Ohm from the center pin to shield on the cables connector with a
semiconductor setting on the DVM.
Try both directions as the diode can be installed either way.
If you can "see" the diode that way it is most certainly good.
I
Ulf,
I have never had a 5065A with a bad or malfunctioning step recovery
diode in the physics package.
MANY other problems are more likely the cause.
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http:/
I have done this before (years ago) but now I can't seem to get a count
out over the RS232 port.
I scoped pin 2 (pin ground) and can't see any data no matter what I try.
I seem to remember a "secret" trick from back then but can't recall it.
I'm counting time difference between two 1PPS signals
Jorge,
The longer Tau (BLUE) was measured against an excellent HP5065A Rubidium.
The shorter Tau (Red) was measured against an excellent FTS 1200 Quartz.
Hope that helps.
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsub
Thanks for the inputs!
I downloaded RealTerm and I could (eventually) get the unit send a
response but could not get it to change frequency.
Then I noticed you have to send an XOR checksum byte at the end of that
command! Duh.
Worked fine then.
Anyway I can now program the frequency in an alter
Hi,
I have a few FE-5680A, one version with two labels and another version B
with one label.
The version B can be talked to with Hyperterminal or Ruby4 and does not
work with VK4XV's program.
The two label version I can only get to talk with VK4XV's
FE-5680Calibrator program.
I found info for t
Ulf,
Here is the schematic of the late version A3.
For some reason when I rotate it won't save rotated so it's upside down!
When I get the parts lists and theory/alignment pages scanned I'll send
them to you off list.
A friend dug up a copy of my Gerber file
What I think I might do is get
Hi,
I just listed a nice tested FE5680A on eBay
http://ebay.us/vkiYWa?cmpnId=5338273189
I have several more in testing that will be listed also.
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.f
Ulf,
I can scan the 2644A schematic and parts list. It might be a day or so.
I also have an ExpressPCB file of a 2644A board I made.
I have retrofitted that board into several (8 or so) A3 modules.
I'll also add a PIX of a partially populated one.
You have the boards made with a 2MM thickness
Ulf,
The A1 modules are most likely OK.
They do not need stellar performance for the 5065A to easily beat spec.
The A3 modules are another matter!
If you are indeed feeding them with 1VRMS and can't get a good output at
J8 then something is not right!
HP made several versions of the A3, the se
I see by searching around I see that the FE5680A uses a MAX913 comparator
to square up the signal.
Has anyone drawn out the schematic of how that is implemented?
I want to try one for a project but the data sheet does not show
examples.
Cheers,
Corby
Luciano,
You should "Ohm out" the lamp connector shield to the chassis with
nothing connected to the connector.
Depending on how your optical unit is mounted there is a good chance the
lamp assy is grounded to the chassis through the threaded stud!
Especially so if the optical is the newer unpaint
Hi,
Thought I'd see if anyone has some "dead" FE 5650A or FE 5680A
(the rev B). I'm looking for a few of the synthesizer modules
for some experiments. I don't need the rest of the unit.
It's the board with the two tiny pushbuttons on it. See PIX.
Willing to pay, but not too much!
Cheers,
Corby
Luciano,
I agree entirely!
I like the motto "do no harm"!
When I try a mod such as replacing the dead op amp on the A9 board. I
make before and after tests to make sure no degradation has occurred.
Since this means parts in 10 -14th AD at 128 Seconds most don't have the
capability. However a lot
>> C-field polarity switch. An experiment. If nothing else
>> I will be able to measure the residual magnetic field.
There is no requirement to do any thing other than switch the C-field
polarity.
No optical stuff needed.
The PRS10 switches the C-field polarity at a 5HZ rate to reduce
Hi,
I'm feeding 5.0 MHZ and 5.01MHz into an HP10514A mixer.
A buffer and a 12dB attenuator feed each input and a 50 Ohm buffer amp
(10Mhz) is on the output.
I get a nice sine output but get the 1Hz as amplitude variations.
Playing with input levels I can minimize the variations but the best
Magnus and Tom,
Thanks.
I'm not (and don't want to be!) a phase noise nut!
However I am an Allan Deviation nut and have documented many 5065A with
the 10811 retrofit that drop into the -14ths between 64 and 128 Sec and
the best show 4.5X10-14th at 1000 Sec.
So I'd say the original circuit does
Magnus, You mentioned:
"The produced noise is at least 10 dB worse than you
would expect. This impacts long term stability response as I have
reported earlier."
Can you refer me to the info you posted earlier or elaborate?
Thanks,
Corby
___
time-nuts
Hi all,
Attached is a PIX showing the opamp pinout!
Cheers,
Corby___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
Luciano,
Hi I understand your A9 is the older version like the one in my post but
with the original opamp module.
I tested the 5065A with an unmodified and then one with the LH156H
mounted and the 24 Hour phase plots were both clean and the AD were the
same.
My lab is not climate controlled so
This NLTL is cheaper @ $2436.56!
MLPNC-7100S1SMA800
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
Hi,
I have a manual but it does only goes up to serial prefix 1836A and
therefore does not have the manual changes for the 1844A series.
Actually I have one page I photocopied years ago.
The top of the page reads:
MANUAL CHANGES MODEL 5062C and 5062C OPT. 010 Page 3
It shows steps 10 thru 23 o
Hi,
Doing some experiments and need HP 5065A A3 and/or HP5062C A10 modules.
They are the 5 to 60 MHz and 5 to 90 MHz multiplier modules.
Anyone have some laying around?
Cheers,
Corby Dawson
___
time-nuts mailing list -- time-nuts@lists.febo.com
To
Poul-Henning,
Hi!
I never use the XY method in the manual.
It's much easier just to use the scope in the normal mode.
I don't try to synch the scope, just use the fine horizontal control to
give me a few cycles on the trace with it close to stationary (slow
roll).
The splitting is easy to adju
The hp 00105-6013 and its variants used in the older 105A, 5061A, 5065A,
and a couple counters also has a crystal filter (5Mhz). I believe it's
the last HP oscillator to do so. If your output amplitude seems low try
tweaking the filter adjustment!
Cheers,
Corby
_
If whoever bought it needs advice I have repaired a couple of them.
It does not have a dewar.
Both the units I worked on had low to mid parts in 10 -13th from 1 to 100
Sec.
They do take 3 to 4 hours to warm up so don't be impatient.
Aging wont slow down for several weeks.
Cheers,
Corby
Luiz,
When shopping for a used tube look for a standard "mini" tube like the
one in the ebay listing.
https://www.ebay.com/itm/HP-Agilent-5061A-Cesium-Frequency-Standard-w-Opt
-01-C13-Good-Working-Unit/233521981160?hash=item365efea6e8:g:HeAAAOSwY2pe
Z~fB
Don't trust any option 4 high stability t
Attila,
I believe your original question was how to compensate for atmospheric
pressure changes on the cell.
It is the cell that is affected by pressure NOT the lamp!
This post gives some info.
https://www.febo.com/pipermail/time-nuts/2016-May/097829.html
Cheers,
Corby
_
Bob,
I just might play at the mixing to see if it will work!
Hmmm, 16 oscillators give a cold current of 12.8 Amps!
The direct sellers you find with Google sell them for <$20.00 each.
One of them:
https://www.teewtfstore.com/index.php?main_page=product_info&products_id=
244548
This seller (c
Magnus,
If you apply a +20V supply to the lamp connector you should see 125-150ma
unlit and it drops bit when it lights.
Also measure from the lamp connector center pin to the outside conductor
with an Ohmmeter.
You should have around 3.33K. The 1.33K resistor (in series with a 2.0K)
is a commo
Hi,
They keep coming out of hiding!
Currently my list shows 246 total units of which 26 are the latest prefix
2816A units.
Anyone that has one that hasn't send me their Serial number please do!
Cheers,
Corby Dawson
___
time-nuts mailing list -- tim
Hi,
The oldest manual I have for the 5065A is for a prefix 1220A and the
oldest change it lists is for the prefix 820 units.
Does anyone have an older manual that is for or lists the changes for a
prefix 808 unit?
Need the info for the front panel adj mag field/loop open/operate switch.
All the
Jim,
The filament is a hot wire ionizer that functions to ionize the atoms in
the beam so that the mass spectrometer will be able to steer them to the
electron multiplier. It is a thin ribbon and not likely to be reattached
once it burns open.
Cheers,
Corby
The pressure sensitivity for a classic design can easily be eliminated.
I'm pretty sure that the old Varian R20 cell was mostly immune.
Either using the R20 design or stiffer convex ends in a modern design
would work.
Also a sealed optical unit has been used to get rid of the pressure
problem
Well I have been looking at the data in the
https://www.researchgate.net/publication/325499937_A_portable_cold_87_Rb_
atomic_clock_with_frequency_instability_at_one_day_in_the_10-15_range
link and find that maybe they are overstating their performance!
In the plot of figure 5 my HP 5065A almost
Jim,
The ion pump supply is fine if the Cs oven reading is OK. A zero reading
is fine on the Ion pump current.
Yes do check the ionizer filament continuity and if its OK check the
voltage across it. Should be around 1 VDC.
If all that looks good pull J1 off A7 and feed it into a high impedance
The following references describe the main failure mode of Rubidium lamps
which is Rubidium depletion.
If the thermal design is correct and the oven and supporting circuitry
are working properly any
condensed Rubidium will be redistributed (back into the tip-off region)
during operation.
On the
JF, Reference your statement:
"Sorry, but I don't agree with your first statement about the 5065A :
after long use, the rubidium plates on the inner envelope of the lamp
(like silver on a mirror) and years after years the Rb light and photo I
decreases."
After working on the 5065A for over 40 yea
Well I can't figure out how to attach the link but if you search for "hp
5071a shipping exemption" in google you will find :
"PDF] Shipping Instruction - Cesium & Rubidium ... - Microsemi how to"
Click on it and it will open a PDF of the form.
You will see that it exempts most requirements, the
There are two separate Rubidium migration problems.
The first is Lamp flooding which occurs when too much Rubidium enters the
main bulb and plates onto the bulb envelope. (usually after long storage
or storage at high temperatures) This mainly in the small telecomm
Rubidiums due to design flaws. T
Hi,
How many of you leave your 5065A on all the time?
Approximately how many years have you had it running without major
maintenance?
My current "gold standard" 5065A has been running for over 5 years.
Cheers!
Corby
___
time-nuts mailing list -- ti
There is an 5065A on Ebay that has the earliest SN I have ever seen.
808-00031 or maybe 00051?
Maybe the first one sold?
If the lamp oven has not fried it might be a fun project.
It has the Patek analog clock.
Cheers,
Corby
___
time-nuts mailing l
Walter,
The 10811 uses an SC cut crystal and a more modern oven control circuit.
Much better short term stability and warmup than the 10544 it replaced!
Cheers,
Corby
http://www.leapsecond.com/museum/10544/1972-Oct-hp-10544A.pdf
http://www.leapsecond.com/museum/10811a/90027-1.pdf
__
Luiz,
Found some more info on replenishing the Hydrogen in the Kvarz CH1-76 and
CH1-75.
Anders had the procedure pretty close for a fully charged canister from
the vendor.
However recharging the original is a bit more challenging!
Use care and protective gear from the high and low temperatures
Hi,
At operating temperature the lamp, filter cell (if used) and the
resonance cell only have gaseous Rubidium in them.
Only exception is early designs that have a "stem" on the resonance cell
that exits the cavity.
There is a small amount of liquid Rubidium in the stem and in the 5065A a
thermo
Check the picture out here:
https://www.eevblog.com/forum/metrology/efos-maser-prototype-in-museum-di
splay/new/#new
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/ti
Perrier,
Hi!
Depends on the type and model, Active or Passive Maser etc.
I believe new active Masers run in the 1/4 million dollar range.
T4 science offers some nice Passive Masers but I don't know the cost.
pH Maser 1008 https://www.t4science.com/products/phmaser-1008/
On the basis of just a
Luiz,
Ch1-75 Hydrogen storage details.
“The compound LaNi5H, is used for storing molecular hydrogen.
The LaHi5H, is characterized by high hydrogen partial pressure (2 to 5
atmospheres) at +(20-50) degrees C.
250 grams of the compound contains 18 liters of hydrogen at normal
pressure.
It is suff
When evaluating an instrument with a used tube the beam current is not
the best indicator to look at!
For an HP instrument If the tube label has the EM voltage listed then
with the beam current set to it's proper level check the current EM
voltage.
As the tube ages you will require more and more EM
Luiz,
Once I know the model number of the Maser I can give some advice.
I recharged the Hydrogen bottle of the EFOS2 Maser 4 times in the past
with no problem.
Really depends on the method of Hydrogen storage and if they made
provision for field repair, I.E. threaded fittings vice welded joints.
Taka,
I'm assuming you meant an HP 53132A?
Anyway to make meaningful measurements you need a DMTD setup or some
other resolution expanding scheme.
An HP 5065A would be your best bet to add to your stable!
Between a good cherry picked Quartz and the 5065A you could cover most
bases easily!
Chee
Hi,
A friend directed me to this listing. Nice looking DMTD unit.
Low power and compact!
Has anyone played with one of these yet?
https://www.ebay.ca/itm/123728915157?ul_noapp=true
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.c
Anton,
What you describe sounds promising however more info would be needed to
troubleshoot.
Not sure what monitoring provisions the CH1-76 has, I think there are a
couple time-nuts with that unit that could comment.
There are a lot if causes for a loss of IF in an active Maser and a few
extra thr
Are we expecting any week rollover problems with the receivers we time
nuts like to play with???
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.co
Heinz,
The relay you hear "clicking" is the relay that generates the HV start
pulse for the lamp. Once the lamp starts and is detected by the preamp
circuit the relay stops cycling.
You can pull the OMU and leave it connected up.
Pull the covers off the lamp end of the OMU and the metal rectangu
Hi,
Wanted to warn about the 5065A that has now sold twice on eBay. (Jan 18
and Feb 2) When it first listed I contacted the seller and told him the
optical unit was missing (A12) and he should not call it "fully
functional" Anyway he sold it for his asking price and now it looks like
he just sold
John,
The clock modules from the 5061A and 5065A take a 1PPS input!
I have several I can sell.
However they are not suitable for a portable app as they are power hogs!
Although they do have a circuit that kills the display if the standard is
on battery power, you can then push the button on the
Thanks for the inputs.
Attached is the blurb from the manual on the 5Mhz isolation amps.
I don't want to redesign as the 3 amps are matched for delay and temp and
run at 45 degrees C.
I'll check the output of the amp with a spec-A and select the capacitor
as appropriate.
Cheers,
Corby_
Hi,
I removed this amp from the EFOS2 Maser as it was intermittent.
Of course now I can't get it to fail on the bench!
I have fabricated a new PC board to replace it and have the components on
hand.
Note the 12pfd cap on the collector .
Some notes I have indicate is select at test and that is
Hi,
I'll throw my two bits in!
Diodes from Efratom FRS, FRK, and M100 are made for 60Mhz drive and
probably would be a good fit.
I'll take a look and see if I have any junkers.
All diodes used in Rubidiums are inside the cell oven so operate at a
high temp anyway.
I agree with Ed, swapping A3
John,
I have repaired several with this problem.
If you want I'll contact you off list with the details and PIX.
Very basically:
Dig out potting (don't start until I send details!)
remove oven cylinder
rewind oven coil
add new thermistor if needed
install and wire new oven
measure temp and sele
Well finally caught it while it was acting up again!
Had to add an audible alarm to help me catch it.
The 1st L.O. (1440Mhz) dies completely and also the 20Mhz TTL front
panel output dies.
Both the 1440Mhz and 20Mhz are derived from the 180Mhz signal.
So now need to see if the 5Mhz input to 18
Forgot to mention that with the problem occurring, and at the same time I
observed the good cavity output on the spec-A, feeding a signal from an
8660D
synthesizer into the LNA showed a zero IF level also. So it's downstream
from there.
Dana,
I have found that "watchful waiting" before jumping
Hi,
See
https://www.ebay.com/itm/digital-clock-module-for-HP5065A-or-HP5061A-freq
uency-standard-working/323360298547
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/t
Hi,
I just listed an FTS 1000A-100 oscillator on eBay.
Fully tested, see plot in listing.
Also will be listing some 10811 (various types) and some FE405B soon.
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go
Well I'm trying this out again.
I have two "enhanced" NOT "Super" HP 5065As I'm working on and decided to
ensemble them together, if that's applicable to only two units?
Attached is a plot against my FTS 1200 and Maser.
Pretty neat.
I'm working on an easy way to lock them together for such work
Hi,
I remember a few that had machine shops volunteering to help with
machining last year but can't remember who!
I have a 2 and 3/8" diameter cylinder 1.45" long.
It needs nine 1/6" deep X 1/16" wide grooves machined in the
circumference and adding some length to a slot already existing running
Bert,
Yes the 5062C also used the same synthesizer style as the 5065A and
5061A/B.
Cheers,
Corby
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to https://lists.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the inst
Hi,
My purpose was to provide an inexpensive (<$30.00) and simple way to
replace a defective A1 without degrading the performance the original A1
gave.
The Chinese DDS allows this without having to solder all those tiny pins!
Both styles actually performed better than the original, and the same i
Hi,
Anyone have hookup info for the Bliley NV26T992
https://www.ebay.com/itm/Bliley-Technologies-Crystal-Oscillator-10-0MHz-N
V26T992/181179304420?epid=19019617029&hash=item2a2f20c9e4:g:opQAAOxyOnRR6
T04
Looks to be a cute cleanup oscillator but I can't find any seller that
has pinout info. and
The "shelf life" referred to is only related to tube vacuum without
pumping occasionally.
It was derived from an estimate of how badly a worst case tube would
leak.
Most tubes have an almost perfect vacuum seal and this "shelf life" is
indefinite.
Leaving a 5061A/B on and in the Cs-off mode keep
94 matches
Mail list logo