Question about HP3586B and measuring Power.
One of the inputs on the 3596B is a 75ohm, another is a 10k ohm//50pf. ?I can understand with a Voltage across a 75 ohm resistor how? to get a power reading. What happens when you switch the unit to 10k ohms. Does it start measuring Voltage across a 10k, and do that calculation. ?The question arose when as? practice for OpenOffice I thought I'd calculate how the power reading misbehaves, if I terminate the input with 50 ohms and measure a fixed voltage from 1MHz to 32MHz. ?The 50pf throws a changing impedance in the mix. In OpenOffice I combined 50ohms, 10k ohms and the 50pf cap impedance to get a total impedance over the frequency span. Then when I went to calculate power, I didn't know where the machine would be referenced. ?Please note, my concern is not really to do the measurement this way is is just an exercise to practice OpenOffice and draw a graph of the error.
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Re: Just purchased HP 3586B--EBAY
Hi George, I don't know. I'll receive the unit this week, I'll see if I bought trouble or if I got a deal.
????????????????????????? Qmavam
|
Re: Plan to deep cleaning my gear
I keep hearing folks here mentioning water penetration
of circuit board substrates, I think I can help you lay
that myth firmly to rest. The process of making pcb's
has always involved many long steps where the board is
entirely immersed in water or water based solutions.
Between each of these steps, the board is immersed in
pure clean water as the etchants, and plating solutions
are rinsed off of the board.
One poster mentioned a board losing its high insulation
value due to water washing. I think the resistance was
damaged not from the water, but rather from what was in
the water, and not from what soaked into the board, but
rather from what was left behind on the surface of the
board.
Detergents come in two basic types, ionic and non ionic.
Ionic based surfactants are great cleaners, but are also
highly conductive of electricity. If not rinsed fully,
they leave a conductive film. This film is often used
to dissipate static charge from plastic surfaces, like
meter windows.
Also, not all water is equal. Hard waters, and acid
neutralized waters, have high mineral content, which is
in the form of salts. If the water is allowed to
evaporate on the board, it will leave a conductive
residue of a particularly nasty type: one that changes
its resistance with ambient humidity.
-Chuck Harris
Adrian Nicol fenland787a@... [hp_agilent_equipment] wrote:
toggle quoted message
Show quoted text
I understand the desire to try and get the insides to look like new! Like Paul, I guess I have 50+ bits of oldish HP and Tek equipment, but I'm not sure I would do what you intend, especially with water!
I recall that in the 60's through to the early 80's water washable fluxes were not necessarily used and PCBs were often expected to be cleaned with CFCs (ICI Arklone and the like) to get the rosin based fluxes off, so some components were not sealed and not meant to get wet!
Early PCBs often meant for hand assembly did not have a solder resist either so there may be a small risk of moisture penetration of the FR4?
I clean things that need it, suspect areas of PCBs due to contamination, old flux from re-work, switches and so on with IPA, dust I blow off with the shop airline, case parts, yes soap, water and brush (and solvent where safe and needed for sticker residue) but the 'aint broke don't fix' mantra is my guide!
|
Hello,
sorry for being a bit slow to respond here. The Fluke313 Sounds interesting - would you be willing to ship it inside the USA to a freight forwarder?
---
With best regards
Tam HANNA (emailing on a BlackBerry PRIV)
Enjoy electronics? Join 6500 other followers by visiting the Crazy Electronics Lab at Am 15. Oktober 2017 22:25:42 MESZ schrieb "Frank Hughes hp_ciscovss@... [hp_agilent_equipment]" :
?
Hi, I'm having trouble lifting heavy things now (surgery on both rotator cuffs), and the son will soon complete his Computer Engineering degree, move away, and then I'll try to move these and be scolded (again) by the surgeon. Let me know if you want photos. All work, unless noted.
I realize the shipping costs for the heavy things make them less attractive, but trying here first. Located in central Fla.? Bring a chain saw.....
Thanks and 73 Frank Hughes KJ4OLL
HP 6521A 0-1kv DC, 0-200ma, 110vac input $100 plus shipping HP 6268B 0-40vdc, 0-30A, 240vac input $250 plus shipping Harrison 6267A, 0-36vdc, 0-10A, 110 vac input, amp meter does not work. $50 plus shipping Harrison 6367A??0-36vdc, 0-10A, 110 vac input, $50 plus shipping HP 6434B 0-40vdc, 0-25A, 110 vac input $150 plus shipping HP 6237B, +18vdc @ 1A, + 20 VDC @ .5A, -20VDC @ .5A, 110vac input, $50 plus shipping HP 6289A, 0-40vdc, 1.5A, 110vac input $50 plus shipping HP 230B RF power amplifier, 10mhz-500mhz, 110vac input $150 plus shipping HP 334A Distortion Analyzer, 110vac input, $125.00, plus shipping HP 3400A RMS voltmeter, 110vac input, $50 plus shipping HP 11710B Down Converter, 110vac input, $100 plus shipping Fluke 313A Voltage Calibrator, 0-50vcd, 0-2A, 110vac input, needs calibration, $75, plus shipping
?
|
Re: Plan to deep cleaning my gear
I had to remove BI/Beckman trimpots from our products at somewhere around 2000 because they would fail after the boards were cleaned. We switched to Bourns, and the problem went away. BI denied that they had a problem, but later they acknowledged that their O-rings were defective as they tried to lure us back.
We used an industrial circuit board cleaner, with a citrus based solvent that was diluted with water. This was followed by an overnight bake in a 105°F dryer.
toggle quoted message
Show quoted text
-----Original Message----- From: "Mark Goldberg marklgoldberg@... [hp_agilent_equipment]" <hp_agilent_equipment@...>
Sent: Oct 16, 2017 9:34 AM
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] Plan to deep cleaning my gear
I agree with this. I have been involved in many product developments over
40 years ( not for HP) and would not use anything but >99% IPA or DI water,
and only if the parts are rated to be cleaned with these solutions. If you
don't know if they are rated, they may be damaged. Some trimpots,
connectors, etc may not be cleanable without damage. The industry did use
Acetone and Freons, but due to safety reasons, those are much less common
now.
Mark
On Oct 16, 2017 5:48 AM, "Adrian Nicol fenland787a@...
[hp_agilent_equipment]" <hp_agilent_equipment@...> wrote:
I understand the desire to try and get the insides to look like new! Like
Paul, I guess I have 50+ bits of oldish HP and Tek equipment, but I'm not
sure I would do what you intend, especially with water!
I recall that in the 60's through to the early 80's water washable fluxes
were not necessarily used and PCBs were often expected to be cleaned with
CFCs (ICI Arklone and the like) to get the rosin based fluxes off, so some
components were not sealed and not meant to get wet!
Early PCBs often meant for hand assembly did not have a solder resist
either so there may be a small risk of moisture penetration of the FR4?
I clean things that need it, suspect areas of PCBs due to contamination,
old flux from re-work, switches and so on with IPA, dust I blow off with
the shop airline, case parts, yes soap, water and brush (and solvent where
safe and needed for sticker residue) but the 'aint broke don't fix' mantra
is my guide!
On Monday, October 16, 2017 5:26 AM, "Calvin Guan guancalvin@...
[hp_agilent_equipment]" <hp_agilent_equipment@...> wrote:
Hi,
I am thinking of deep cleaning of my gear. 8566 SA, 8510 VNA, 8515A
S-parameter test set, 8350/83592 sweeper.
I think I am going to remove all PCBs, soak them into clean water, brush
them and dry them with hair dryer as soon as I can.
For delicate microwave assemblies like DC, YIG, YTFM, mixer and ovenized
crystal, and CRT display, I will just brush dirt off the surface and leave
them alone.
For sticky keys, soak the keyboard assembly into IPA, rinse them and dry
them as quickly as I could.
Sounds like a plan?
Thank you!
Calvin
Michael A. Terrell
|
Re: Plan to deep cleaning my gear
I agree with this. I have been involved in many product developments over 40 years ( not for HP) and would not use anything but >99% IPA or DI water, and only if the parts are rated to be cleaned with these solutions. If you don't know if they are rated, they may be damaged. Some trimpots, connectors, etc may not be cleanable without damage. The industry did use Acetone and Freons, but due to safety reasons, those are much less common now.
Mark
?
I understand the desire to try and get the insides to look like new! Like Paul, I guess I have 50+ bits of oldish HP and Tek equipment, but I'm not sure I would do what you intend, especially with water!
I recall that in the 60's through to the early 80's water washable fluxes were not necessarily used and PCBs were often expected to be cleaned with CFCs (ICI Arklone and the like) to get the rosin based fluxes off, so some components were not sealed and not meant to get wet!
Early PCBs often meant for hand assembly did not have a solder resist either so there may be a small risk of moisture penetration of the FR4?
I clean things that need it, suspect areas of PCBs due to contamination, old flux from re-work, switches and so on with IPA, dust I blow off with the shop airline, case parts, yes soap, water and brush (and solvent where safe and needed for sticker residue) but the 'aint broke don't fix' mantra is my guide!
?
Hi,
I am thinking of deep cleaning of my gear. 8566 SA, 8510 VNA, 8515A S-parameter test set, 8350/83592 sweeper.
I think I am going to remove all PCBs, soak them into clean water, brush them and dry them with hair dryer as soon as I can.
For delicate microwave assemblies like DC, YIG, YTFM, mixer and ovenized crystal, and CRT display, I will just brush dirt off the surface and leave them alone.
For sticky keys, soak the keyboard assembly into IPA, rinse them and dry them as quickly as I could.
Sounds like a plan?
Thank you!
Calvin
|
Re: Plan to deep cleaning my gear
I understand the desire to try and get the insides to look like new! Like Paul, I guess I have 50+ bits of oldish HP and Tek equipment, but I'm not sure I would do what you intend, especially with water!
I recall that in the 60's through to the early 80's water washable fluxes were not necessarily used and PCBs were often expected to be cleaned with CFCs (ICI Arklone and the like) to get the rosin based fluxes off, so some components were not sealed and not meant to get wet!
Early PCBs often meant for hand assembly did not have a solder resist either so there may be a small risk of moisture penetration of the FR4?
I clean things that need it, suspect areas of PCBs due to contamination, old flux from re-work, switches and so on with IPA, dust I blow off with the shop airline, case parts, yes soap, water and brush (and solvent where safe and needed for sticker residue) but the 'aint broke don't fix' mantra is my guide!
On Monday, October 16, 2017 5:26 AM, "Calvin Guan guancalvin@... [hp_agilent_equipment]" wrote:
?
Hi,
I am thinking of deep cleaning of my gear. 8566 SA, 8510 VNA, 8515A S-parameter test set, 8350/83592 sweeper.
I think I am going to remove all PCBs, soak them into clean water, brush them and dry them with hair dryer as soon as I can.
For delicate microwave assemblies like DC, YIG, YTFM, mixer and ovenized crystal, and CRT display, I will just brush dirt off the surface and leave them alone.
For sticky keys, soak the keyboard assembly into IPA, rinse them and dry them as quickly as I could.
Sounds like a plan?
Thank you!
Calvin
|
HP 5343A S/N 2440A Service Manual
Looking for a HP 5343A Service Manual for S/N 2440A prefix. All kinds a manuals for the 2014A prefix. I am working on issues with the 10Hz to 500Hz section of my counter and the A3 Direct Counter PCBA P/N 05342-60040 is different than the information in older SM. Anyone have any information on this Counter Board. Tnx Rich KQ6EF
|
Wanted: HP1346A/HP1347A EPROMS and service manual
Hi,
Ansgar Kueckes have gotten hold of a prototype HP1347A used to produce the "NORAD" graphics for the Wargames movie, and it does not match the 1346/1347 OPM manual on Keysights homepage.
For purely data-archaeological reasons, I am interested in getting hold of the contents of the ROMs on the final production version, to compare it with this prototype code, and it would also be very nice to get hold of a service manual if possible.
For more info see:
and:
Thanks in advance,
Poul-Henning
|
Hi all,
one of my other projects I'm working on is a 5342A which does not count on the high frequency input.
I checked the sampler according to the service manual. I used a 34401A for the resistance meausrement and got 22k in forward bias and >3M in reverse bias. This is quite different from the values stated in the service manual; however, when I look at the schematic,
I think it should be possible to test the sampler with the diode test function. I did that, and I found out that in forward bias, I have approx. 0.4 volts, and reverse bias is open. So it looks like a pretty nice diode. However I cannot compare to other samplers,
and the service manual also tells that the resistance measured can vary greatly if not exact 1mA measuring current is used.
Does that sampler look good to you guys, or is it probably broken? because if it is broken I think it makes no sense to invest additional time to fix things.
Tobias, HB9FSX
|
Re: Plan to deep cleaning my gear
Hi Calvin
My recommendation is you just dust equipment
out clean edge connectors and service fan assemblies / motors / bearings
In short if it is not broken do not fix it
I only use soap and water on cases
?
I would never do a deep clean as you describe
with any of my 50 plus hp items
For sticking keyboards I disassemble them to
clean them
Regards Paul B
From:
hp_agilent_equipment@...
[mailto:hp_agilent_equipment@...]
Sent: 16 October 2017 05:27
To: hp_agilent_equipment@...
Subject: [hp_agilent_equipment]
Plan to deep cleaning my gear
Hi,
I am thinking of deep cleaning of my gear. 8566 SA, 8510 VNA, 8515A S-parameter
test set, 8350/83592 sweeper.
I think I am going to remove all PCBs, soak them into clean water, brush them
and dry them with hair dryer as soon as I can.
For delicate microwave assemblies like DC, YIG, YTFM, mixer and ovenized
crystal, and CRT display, I will just brush dirt off the surface and leave them
alone.
For sticky keys, soak the keyboard assembly into IPA, rinse them and dry them
as quickly as I could.
Sounds like a plan?
Thank you!
Calvin._,_.___
With 4.5 stars in iTunes, the Yahoo Mail app is the
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Checked by AVG -
Version: 2016.0.8013 / Virus Database: 4782/15039 - Release Date: 10/16/17
|
Re: Plan to deep cleaning my gear
Just be careful about possible water ingress at the edges of the fiber glass boards. It can actually cause some problems with high impedance circuits (Been there...) I would use an ordinary oven and set it to ... 50-60 Degrees Celsius and put the boards in there for about an hour.
BR
Ulf Kylenfall - SM6GXV
|
Re: YIG device failure modes
I regularly check eBay for spare parts list as “working”. Just keep looking. You would get what you want one day.
Calvin
toggle quoted message
Show quoted text
Jeff, re-fitting a different YIG was an option which I was thinking about when I repaired my 8341A sweeper. The YIG is a 5086-7323 which operates from 2.3 to 7GHz and tuning coil sensitivity is 24mA/GHz. However, I wonder how accurate those 24mA/GHz are. For instance, if I fitted another YIG with 20mA/GHz, would that work as well? the YO driver used can be calibrated for offset and gain... Have you ever fitted a replacement YIG? What about those SYTMs HP has used sometimes (switchable YIG tuned multiplier)? is there any replacement? And do you have an idea what the reason could be for the semiconductor to fail? assuming the operating voltages were ok, is there some chemical aging process or so which destroys the semiconductor some day? because there are instruments which are 30 yrs old and still working, but the older they get the more difficult it will be to find spare parts I guess; if the YIG fails and cannot be replaced, the whole instrument is nothing more than a really heavy paperweight....
Tobias HB9FSX
-------- Original message -------- Date: 10/16/17 06:01 (GMT+01:00)? Subject: Re: [hp_agilent_equipment] YIG device failure modes?
?
I have tested several hundred YIG devices over my career. (Have drawers full of them, its a sickness)? I have seen more misaligned YIG support rods or bad oscillator semiconductors than I have seen bad coils. ? Sometimes the coil connection fails at the solder point due to wire wrap/crimp failure and current heating the joint, eventually it opens, have fixed three like this. Some model YIGs have high coil current and if poorly cooled/heatsunk, the enamel insulation seems to fail and create a sorted coil. Only have seen one like this, but opened it up and figured out the failure. ? Other times, the polystyrene rod that holds the YIG sphere warps & twists over time from heat?& general plasticizer failure?and misaligns the magnetic axis of the sphere with the field, pretty tough to fix this, major cause of holes and high end tailing off.? And, of course, when the semiconductor device fails (Gunn diode in older X band and up, Bipolar thru 12 GHz for old ones, FET now), you are done. ? It is possible to re-fit different YIGs into various pieces of gear, but re-scaling the drivers to the right coil sensitivities can be challenging/time-consuming. ? The worst thing to deal with is the wideband? YIG tuned multipliers. Never had much luck bringing these back to life once they go south. ? YMMV Jeff Kruth WA3ZKR ? ?
Hi guys. Over the years I have read a lot about yigs going bad specifically their coils seem to go bad. Is there anything that can be done pre-emptively to secure their longevity? And what exactly happens? Do the coils open due to excessive current (like a fuse?) I know there is an issue where the sphere sometimes moves and gets located incorrectly IIRC. I don’t know what causes that, perhaps excessive force? But I am interested in the coil issue. I have no yig issues at the moment, which seems like a good time to try to prevent it?
Eugene W2HX
|
Re: Plan to deep cleaning my gear
As a fan of cleaning old electronics I would make a few comments:
Look at a number of past threads on cleaning,
Not everything really needs total cleaning, some things should not be
"cleaned" and some labels can be removed with water. Other things need to be
cleaned but can't be cleaned with water/soap (such as HP clear vinyl tubing
in power supplies)
Start off with some things that are worth less.
To really get stuff off, you will need a surfactant but surfactants can
remove labels and other marks so you have to be careful what and where.
I would not soak pcbs, that can get a lot of water into stuff like pots, and
transformers, carefully brush and hose off with water. Avoiding
spraying/soaking into stuff like pots and transformers.
I would not "dry" with a hairdryer too hot too quick, blow off as much water
(taking as much dissolved salts) as you can with lots of cold air, I use a
clean leaf blower on at night when there is lots of water in the air(no
static).
Then possibly rewash, reblow, rewash and reblow (triple rinse)
Then dry in a 120F ish temp with some air movement for 24 or more hours.
I have used an old fruit dehydrator, worked great, that died from too much
use, Now I have been using an oven with a 50W bulb and small crack in door
where cord goes in (gets just to 115F)
Take lots of pictures before things are taken apart, saved me many a time
Just some thoughts
John
toggle quoted message
Show quoted text
-----Original Message-----
From: hp_agilent_equipment@...
[mailto:hp_agilent_equipment@...]
Sent: Sunday, October 15, 2017 9:27 PM
To: hp_agilent_equipment@...
Subject: [hp_agilent_equipment] Plan to deep cleaning my gear
Hi,
I am thinking of deep cleaning of my gear. 8566 SA, 8510 VNA, 8515A
S-parameter test set, 8350/83592 sweeper.
I think I am going to remove all PCBs, soak them into clean water, brush
them and dry them with hair dryer as soon as I can.
For delicate microwave assemblies like DC, YIG, YTFM, mixer and ovenized
crystal, and CRT display, I will just brush dirt off the surface and leave
them alone.
For sticky keys, soak the keyboard assembly into IPA, rinse them and dry
them as quickly as I could.
Sounds like a plan?
Thank you!
Calvin
------------------------------------
Posted by: Calvin Guan <guancalvin@...>
------------------------------------
------------------------------------
Yahoo Groups Links
|
Re: Plan to deep cleaning my gear
Hi
I would not soak the PCBs. Just blow away dirt using air. Somewhere I once read that the laminate of the PCBs can sponge up the water and I don't know whether this is nice. Better not to try it, your instruments are too nice to destroy them by cleaning
:-) if it was a PCB from something really ordinary, I would give it a try, but for sure not with those gems! ;-)
Tobias
toggle quoted message
Show quoted text
-------- Original message --------
From: "Calvin Guan guancalvin@... [hp_agilent_equipment]"
Date: 10/16/17 06:27 (GMT+01:00)
To: hp_agilent_equipment@...
Subject: [hp_agilent_equipment] Plan to deep cleaning my gear
?
Hi,
I am thinking of deep cleaning of my gear. 8566 SA, 8510 VNA, 8515A S-parameter test set, 8350/83592 sweeper.
I think I am going to remove all PCBs, soak them into clean water, brush them and dry them with hair dryer as soon as I can.
For delicate microwave assemblies like DC, YIG, YTFM, mixer and ovenized crystal, and CRT display, I will just brush dirt off the surface and leave them alone.
For sticky keys, soak the keyboard assembly into IPA, rinse them and dry them as quickly as I could.
Sounds like a plan?
Thank you!
Calvin
|
Re: YIG device failure modes
Jeff,
re-fitting a different YIG was an option which I was thinking about when I repaired my 8341A sweeper. The YIG is a 5086-7323 which operates from 2.3 to 7GHz and tuning coil sensitivity is 24mA/GHz. However, I wonder how accurate those 24mA/GHz are. For
instance, if I fitted another YIG with 20mA/GHz, would that work as well? the YO driver used can be calibrated for offset and gain... Have you ever fitted a replacement YIG?
What about those SYTMs HP has used sometimes (switchable YIG tuned multiplier)? is there any replacement?
And do you have an idea what the reason could be for the semiconductor to fail? assuming the operating voltages were ok, is there some chemical aging process or so which destroys the semiconductor some day? because there are instruments which are 30 yrs
old and still working, but the older they get the more difficult it will be to find spare parts I guess; if the YIG fails and cannot be replaced, the whole instrument is nothing more than a really heavy paperweight....
Tobias HB9FSX
toggle quoted message
Show quoted text
-------- Original message --------
From: "kmec@... [hp_agilent_equipment]"
Date: 10/16/17 06:01 (GMT+01:00)
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] YIG device failure modes
?
I have tested several hundred YIG devices over my career. (Have drawers full of them, its a sickness)? I have seen more misaligned YIG support rods or bad oscillator semiconductors than I have seen bad coils.
?
Sometimes the coil connection fails at the solder point due to wire wrap/crimp failure and current heating the joint, eventually it opens, have fixed three like this. Some model YIGs have high coil current and if poorly cooled/heatsunk, the enamel insulation
seems to fail and create a sorted coil. Only have seen one like this, but opened it up and figured out the failure.
?
Other times, the polystyrene rod that holds the YIG sphere warps & twists over time from heat?& general plasticizer failure?and misaligns the magnetic axis of the sphere with the field, pretty tough to fix this, major cause of holes and high end tailing
off.
And, of course, when the semiconductor device fails (Gunn diode in older X band and up, Bipolar thru 12 GHz for old ones, FET now), you are done.
?
It is possible to re-fit different YIGs into various pieces of gear, but re-scaling the drivers to the right coil sensitivities can be challenging/time-consuming.
?
The worst thing to deal with is the wideband? YIG tuned multipliers. Never had much luck bringing these back to life once they go south.
?
YMMV
Jeff Kruth
WA3ZKR
?
In a message dated 10/15/2017 1:40:13 P.M. Eastern Daylight Time, hp_agilent_equipment@... writes:
?
Hi guys. Over the years I have read a lot about yigs going bad specifically their coils seem to go bad. Is there anything that can be done pre-emptively to secure their longevity? And what exactly happens? Do the coils open due to excessive
current (like a fuse?) I know there is an issue where the sphere sometimes moves and gets located incorrectly IIRC. I don’t know what causes that, perhaps excessive force? But I am interested in the coil issue. I have no yig issues at the moment, which seems
like a good time to try to prevent it?
Eugene W2HX
|
Plan to deep cleaning my gear
Hi,
I am thinking of deep cleaning of my gear. 8566 SA, 8510 VNA, 8515A S-parameter test set, 8350/83592 sweeper.
I think I am going to remove all PCBs, soak them into clean water, brush them and dry them with hair dryer as soon as I can.
For delicate microwave assemblies like DC, YIG, YTFM, mixer and ovenized crystal, and CRT display, I will just brush dirt off the surface and leave them alone.
For sticky keys, soak the keyboard assembly into IPA, rinse them and dry them as quickly as I could.
Sounds like a plan?
Thank you!
Calvin
|
Re: YIG device failure modes
I have tested several hundred YIG devices over my career. (Have drawers
full of them, its a sickness)? I have seen more misaligned YIG support rods
or bad oscillator semiconductors than I have seen bad coils.
?
Sometimes the coil connection fails at the solder point due to wire
wrap/crimp failure and current heating the joint, eventually it opens, have
fixed three like this. Some model YIGs have high coil current and if poorly
cooled/heatsunk, the enamel insulation seems to fail and create a sorted coil.
Only have seen one like this, but opened it up and figured out the
failure.
?
Other times, the polystyrene rod that holds the YIG sphere warps &
twists over time from heat?& general plasticizer failure?and
misaligns the magnetic axis of the sphere with the field, pretty tough to fix
this, major cause of holes and high end tailing off.
And, of course, when the semiconductor device fails (Gunn diode in older X
band and up, Bipolar thru 12 GHz for old ones, FET now), you are done.
?
It is possible to re-fit different YIGs into various pieces of gear, but
re-scaling the drivers to the right coil sensitivities can be
challenging/time-consuming.
?
The worst thing to deal with is the wideband? YIG tuned multipliers.
Never had much luck bringing these back to life once they go south.
?
YMMV
Jeff Kruth
WA3ZKR
?
In a message dated 10/15/2017 1:40:13 P.M. Eastern Daylight Time,
hp_agilent_equipment@... writes:
toggle quoted message
Show quoted text
?
Hi guys. Over the years I have read a lot about yigs going
bad specifically their coils seem to go bad. Is there anything that can be
done pre-emptively to secure their longevity? And what exactly happens? Do the
coils open due to excessive current (like a fuse?) I know there is an issue
where the sphere sometimes moves and gets located incorrectly IIRC. I don’t
know what causes that, perhaps excessive force? But I am interested in the
coil issue. I have no yig issues at the moment, which seems like a good time
to try to prevent it?
Eugene W2HX
|
Re: 3585B Spectrum Analyzer
Good tip Peter. I'll keep that in mind.
Thanks, Peter
ve3poa
|
On my 8566b, if the span is greater than certain MHz, the sweep source is operate in “Lock and Roll” mode - locks to the sweep start frequency then applies a ramp to roll. Calvin
toggle quoted message
Show quoted text
On Oct 15, 2017, at 11:34 AM, edbreya@... [hp_agilent_equipment] < hp_agilent_equipment@...> wrote:
?
I don't know about the screen flickering, but I do think the YTO loop behavior is normal. At wider spans it is not constantly phase-locked - it is driven open-loop with fairly accurate sweep current, and I think possibly re-phase-locked just at the beginning of the sweep each time around. For wide spans, you can't resolve the small frequency error on-screen anyway, but for narrow ones, more stability is needed, so the LO is locked. It's also possible that the narrow spans instead fix the first LO and use the second LO for sweeping - I can't recall for sure, but it should be one of those two schemes.
Definitely get the manual if you haven't already.
Ed
|
Michael A. Terrell
Paul Bicknell
