I forgot to ask, what is your noise floor level at full span?
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On Thu, Apr 11, 2019 at 10:27 AM, amirb wrote:
I assume there are no error messages appearing anymore, right? Any error message about Log amp or step gain amplifiers?
if there is no error and you are sure the attenuator and the input AC/DC coupling are ok (you can even check with oscilloscope by injecting a signal)
then the best and perhaps only way to isolate the problem is by injecting signal at various points and measuring power levels according to the service manual
I dont think this is due to low LO amplitude in any of the converters. otherwise you would get an error message and besides
90dB down is way too much for that. I suspect this is due to a fault in one of the 3 converters or in the Log amp (but not in any of the LO drives)
since you dont have a second spectrum analyzer, I suggest you inject a signal at say -20 or -21dB to the first mixer (make sure span is set to zero)
and then measure the 310.7MHz second IF with an oscilloscope (I hope you have a 400-500MHz scope?) or even a power meter.
if the amplitude is way off then the problem is either the first mixer or the second converter. By the way, you can check the mixer bias voltages coming from A14
In some versions even the first mixer has bias voltage.
Next you can inject a clean 310.7MHz at around -35 or -36dBm to the third IF input (you might have it on the front panel) (you must choose it first in the menus and also choose zero span)
and then you can measure the 10.7 Mhz final IF with an oscilloscope it must be around -15 to -17dBm I think.
On Thu, Apr 11, 2019 at 09:44 AM, Dave Ireland wrote:
I am repairing a HP8560E and until now have been doing well.
The unit on delivery had the classic distorted display and no apparent response to any input though it did sweep it was very slow. 12 Alarms were reported.
Choose the "600 MHz Reference Oscillator Unlocked" first and replacing failed 2N2222A regulator on the 100MHz oscillator which bought the display back and all the alarms disappeared. Best 40c I've ever spent.
Was it completely fixed? No unfortunately not, the input reads about 90dB low. Every thing else looks fine, the resolution band width, span and frequency accuracy all look good. Checked the attenuator and the filter and even went straight into the RF port on the first low band mixer but still 90dB down.
I am at an impass now until I can borrow a decent SA as I do not have anything to measure 3-6GHz.
I did the LO feed through test in the service manual ie centre freq 0Hz, Span 1MHz, input attenuator 0dB and it says the feed through should be between -6 and -30dBm. It says if it is inside this range the RF path following the Low band mixer is operating properly.
Mine is -26dBm, so in the range.
My question is does that test mean that the the Yig, the LO distribution amp, the first mixer LO and IF ports and all the following mixers are operating correctly albeit not 90dB out? If so, the only thing I can think is a faulty RF port on the mixer (sounds unlikely). Also, I suppose if the LO drive was low, maybe 10 dB or so, there would still be feed through but may be not enough level to bias the mixer to mix.
Any though while I wait for a better spec an?
Dave
?
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I assume there are no error messages appearing anymore, right? Any error message about Log amp or step gain amplifiers?
if there is no error and you are sure the attenuator and the input AC/DC coupling are ok (you can even check with oscilloscope by injecting a signal)
then the best and perhaps only way to isolate the problem is by injecting signal at various points and measuring power levels according to the service manual
I dont think this is due to low LO amplitude in any of the converters. otherwise you would get an error message and besides
90dB down is way too much for that. I suspect this is due to a fault in one of the 3 converters or in the Log amp (but not in any of the LO drives)
since you dont have a second spectrum analyzer, I suggest you inject a signal at say -20 or -21dB to the first mixer (make sure span is set to zero)
and then measure the 310.7MHz second IF with an oscilloscope (I hope you have a 400-500MHz scope?) or even a power meter.
if the amplitude is way off then the problem is either the first mixer or the second converter. By the way, you can check the mixer bias voltages coming from A14
In some versions even the first mixer has bias voltage.
Next you can inject a clean 310.7MHz at around -35 or -36dBm to the third IF input (you might have it on the front panel) (you must choose it first in the menus and also choose zero span)
and then you can measure the 10.7 Mhz final IF with an oscilloscope it must be around -15 to -17dBm I think.
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On Thu, Apr 11, 2019 at 09:44 AM, Dave Ireland wrote:
I am repairing a HP8560E and until now have been doing well.
The unit on delivery had the classic distorted display and no apparent response to any input though it did sweep it was very slow. 12 Alarms were reported.
Choose the "600 MHz Reference Oscillator Unlocked" first and replacing failed 2N2222A regulator on the 100MHz oscillator which bought the display back and all the alarms disappeared. Best 40c I've ever spent.
Was it completely fixed? No unfortunately not, the input reads about 90dB low. Every thing else looks fine, the resolution band width, span and frequency accuracy all look good. Checked the attenuator and the filter and even went straight into the RF port on the first low band mixer but still 90dB down.
I am at an impass now until I can borrow a decent SA as I do not have anything to measure 3-6GHz.
I did the LO feed through test in the service manual ie centre freq 0Hz, Span 1MHz, input attenuator 0dB and it says the feed through should be between -6 and -30dBm. It says if it is inside this range the RF path following the Low band mixer is operating properly.
Mine is -26dBm, so in the range.
My question is does that test mean that the the Yig, the LO distribution amp, the first mixer LO and IF ports and all the following mixers are operating correctly albeit not 90dB out? If so, the only thing I can think is a faulty RF port on the mixer (sounds unlikely). Also, I suppose if the LO drive was low, maybe 10 dB or so, there would still be feed through but may be not enough level to bias the mixer to mix.
Any though while I wait for a better spec an?
Dave
?
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I am repairing a HP8560E and until now have
been doing well.
The unit on delivery had the classic distorted
display and no apparent response to any input though it did
sweep it was very slow. 12 Alarms were reported.
Choose the "600 MHz Reference Oscillator
Unlocked" first and replacing failed 2N2222A regulator on the
100MHz oscillator which bought the display back and all the
alarms disappeared. Best 40c I've ever spent.
Was it completely fixed? No unfortunately not,
the input reads about 90dB low. Every thing else looks fine, the
resolution band width, span and frequency accuracy all look
good. Checked the attenuator and the filter and even went
straight into the RF port on the first low band mixer but still
90dB down.
I am at an impass now until I can borrow a
decent SA as I do not have anything to measure 3-6GHz.
I did the LO feed through test in the service
manual ie centre freq 0Hz, Span 1MHz, input attenuator 0dB and
it says the feed through should be between -6 and -30dBm. It
says if it is inside this range the RF path following the Low
band mixer is operating properly.
Mine is -26dBm, so in the range.
My question is does that test mean that the
the Yig, the LO distribution amp, the first mixer LO and IF
ports and all the following mixers are operating correctly
albeit not 90dB out? If so, the only thing I can think is a
faulty RF port on the mixer (sounds unlikely). Also, I suppose
if the LO drive was low, maybe 10 dB or so, there would still be
feed through but may be not enough level to bias the mixer to
mix.
Any though while I wait for a better spec an?
Dave
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Re: Anyone have the 4278A CLIP?
Update:
I would still like to get the CLIP, but found two problems:
The option switch on the CPU board was set wrong, and the wires to the LCD contrast pot were broken.? The instrument now seems to be operating just fine.? The LED on the processor board (in the group of 8) is still lit so it may be normal?
Reading a standard capacitor perfectly, and a few others seem good too.
Gotta love repairs like this.
Peter
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On 4/10/2019 9:23 PM, Peter Gottlieb via Groups.Io wrote: I have the poor quality scan from the Keysight site, but it doesn't include the processor board.
I have a lit up screen with no display.? Power supplies are good.
My unit is serial 2936J09603 which is way later than the range in the manual I have.? The processor board is a much newer design from the layout in the manual.
On power up I get all LEDs on the processor board light up, then they light sequentially, then stop in a pattern of 10000000.? This is the initialization of the LCD, and the troubleshooting guide says the A7 (processor) data acknowledge circuit is faulty.? A CLIP of the processor board sure would help.? I do hear a bunch or relays clicking so the processor is at least talking to other parts of the instrument.
Anyone know where I can find or purchase a CLIP which includes this info?
Peter
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Anyone have the 4278A CLIP?
I have the poor quality scan from the Keysight site, but it doesn't include the processor board.
I have a lit up screen with no display.? Power supplies are good.
My unit is serial 2936J09603 which is way later than the range in the manual I have.? The processor board is a much newer design from the layout in the manual.
On power up I get all LEDs on the processor board light up, then they light sequentially, then stop in a pattern of 10000000.? This is the initialization of the LCD, and the troubleshooting guide says the A7 (processor) data acknowledge circuit is faulty.? A CLIP of the processor board sure would help.? I do hear a bunch or relays clicking so the processor is at least talking to other parts of the instrument.
Anyone know where I can find or purchase a CLIP which includes this info?
Peter
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Re: Correct rack mount bracket?
Steve, your last two sentences are the critical ones¡ªI was not aware! Looking at the weight and depth of the 3456A however, it should have been obvious. I'll use a shelf or other larger instrument underneath to take the stress off of the ears. Jeremy
Jeremy, Yes, those ears will fit a 3456A. They are definitely for use without handles. The ones for use with handles remaining attached have a notch at top and bottom to clear the handles. You will have to remove the handles to use the ones on offer. Note that the screws to mount the ears to the unit don¡¯t appear to be included. The flathead screws that mount the handles are not long enough to use to mount the ears. You¡¯ll also need either a shelf for the unit to sit on or the side mounted slides. The rack mount ears and front frame of the DVM are not designed to support the weight of the unit.? On Apr 10, 2019, at 5:13 PM, Jeremy Nichols < jn6wfo@...> wrote: Is eBay item number:173844545405 the correct rack mounting bracket for my HP-3456A DVM? All these "with handles" and "without handles" descriptions are confusing (if the sellers are even correct).
Jeremy
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Re: Correct rack mount bracket?
Yes, I kept moving instruments around in the rack and between the rack and the bench. When I noticed some distortion in the rack mounting rails (where I had a heavy HP power supply and a couple of other heavy instruments), I bought a bunch of the shelves and have been very pleased with them.
DaveD Sent from a small flat thingy
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On Apr 10, 2019, at 19:56, Steve - Home < steve-krull@...> wrote: Those look nice, Dave! For most of my units I ended up mounting aluminum angle in the racks and aluminum bar stock on the sides of the units, with Teflon tape so everything slides easily. Since the Teflon effectively isolates the chassis¡¯s from the rack I¡¯m in the process of adding individual ground straps for each unit rather than rely on the power cord grounds. On Apr 10, 2019, at 6:12 PM, Dave Daniel < kc0wjn@...> wrote: I¡¯ve ended up using these ¡° AC Infinity Vented Cantilever 2U Universal Rack Shelf¡± items purchase through Amazon instead of HP or Tektronix OEM rack ears. The shelves are a lot easier to install, and they allow easier rack reconfiguration.
DaveD Sent from a small flat thingy Jeremy, Yes, those ears will fit a 3456A. They are definitely for use without handles. The ones for use with handles remaining attached have a notch at top and bottom to clear the handles. You will have to remove the handles to use the ones on offer. Note that the screws to mount the ears to the unit don¡¯t appear to be included. The flathead screws that mount the handles are not long enough to use to mount the ears. You¡¯ll also need either a shelf for the unit to sit on or the side mounted slides. The rack mount ears and front frame of the DVM are not designed to support the weight of the unit.? On Apr 10, 2019, at 5:13 PM, Jeremy Nichols < jn6wfo@...> wrote: Is eBay item number:173844545405 the correct rack mounting bracket for my HP-3456A DVM? All these "with handles" and "without handles" descriptions are confusing (if the sellers are even correct).
Jeremy
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Re: Correct rack mount bracket?
Those look nice, Dave! For most of my units I ended up mounting aluminum angle in the racks and aluminum bar stock on the sides of the units, with Teflon tape so everything slides easily. Since the Teflon effectively isolates the chassis¡¯s from the rack I¡¯m in the process of adding individual ground straps for each unit rather than rely on the power cord grounds.
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On Apr 10, 2019, at 6:12 PM, Dave Daniel < kc0wjn@...> wrote: I¡¯ve ended up using these ¡° AC Infinity Vented Cantilever 2U Universal Rack Shelf¡± items purchase through Amazon instead of HP or Tektronix OEM rack ears. The shelves are a lot easier to install, and they allow easier rack reconfiguration.
DaveD Sent from a small flat thingy Jeremy, Yes, those ears will fit a 3456A. They are definitely for use without handles. The ones for use with handles remaining attached have a notch at top and bottom to clear the handles. You will have to remove the handles to use the ones on offer. Note that the screws to mount the ears to the unit don¡¯t appear to be included. The flathead screws that mount the handles are not long enough to use to mount the ears. You¡¯ll also need either a shelf for the unit to sit on or the side mounted slides. The rack mount ears and front frame of the DVM are not designed to support the weight of the unit.? On Apr 10, 2019, at 5:13 PM, Jeremy Nichols < jn6wfo@...> wrote: Is eBay item number:173844545405 the correct rack mounting bracket for my HP-3456A DVM? All these "with handles" and "without handles" descriptions are confusing (if the sellers are even correct).
Jeremy
|
Re: Correct rack mount bracket?
I¡¯ve ended up using these ¡° AC Infinity Vented Cantilever 2U Universal Rack Shelf¡± items purchase through Amazon instead of HP or Tektronix OEM rack ears. The shelves are a lot easier to install, and they allow easier rack reconfiguration.
DaveD Sent from a small flat thingy
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On Apr 10, 2019, at 18:54, Steve - Home < steve-krull@...> wrote: Jeremy, Yes, those ears will fit a 3456A. They are definitely for use without handles. The ones for use with handles remaining attached have a notch at top and bottom to clear the handles. You will have to remove the handles to use the ones on offer. Note that the screws to mount the ears to the unit don¡¯t appear to be included. The flathead screws that mount the handles are not long enough to use to mount the ears. You¡¯ll also need either a shelf for the unit to sit on or the side mounted slides. The rack mount ears and front frame of the DVM are not designed to support the weight of the unit.? On Apr 10, 2019, at 5:13 PM, Jeremy Nichols < jn6wfo@...> wrote: Is eBay item number:173844545405 the correct rack mounting bracket for my HP-3456A DVM? All these "with handles" and "without handles" descriptions are confusing (if the sellers are even correct).
Jeremy
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I ended up finding a 432A for sale on ebay that included a 478A coaxial thermistor mount. It's in great shape (even still has both feet), but appears to have lost the little screw for mechanically zeroing the meter.
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Re: Correct rack mount bracket?
On Wed, Apr 10, 2019 at 03:13 PM, Jeremy Nichols wrote:
Is eBay item number:173844545405 the correct rack mounting bracket for my HP-3456A DVM? All these "with handles" and "without handles" descriptions are confusing (if the sellers are even correct).
?
Jeremy
?
As I understand it, the thinner instruments such as the 3455/56 voltmeters are 2U, with two screws. Most others are 3U. Really large ones such as the 8664 sig gen and the 8569 spectrum analyzer are 4U. I think what's pictured are indeed 2U rack ears, but you should confirm the measurements. Sean
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Re: Correct rack mount bracket?
Jeremy, Yes, those ears will fit a 3456A. They are definitely for use without handles. The ones for use with handles remaining attached have a notch at top and bottom to clear the handles. You will have to remove the handles to use the ones on offer. Note that the screws to mount the ears to the unit don¡¯t appear to be included. The flathead screws that mount the handles are not long enough to use to mount the ears. You¡¯ll also need either a shelf for the unit to sit on or the side mounted slides. The rack mount ears and front frame of the DVM are not designed to support the weight of the unit.?
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On Apr 10, 2019, at 5:13 PM, Jeremy Nichols < jn6wfo@...> wrote: Is eBay item number:173844545405 the correct rack mounting bracket for my HP-3456A DVM? All these "with handles" and "without handles" descriptions are confusing (if the sellers are even correct).
Jeremy
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Re: Plastic snap-in bottom feet
Not sure about part numbers, but some of them were all plastic?+ metal legs, and others were plastic?+ rubber surface grip + metal legs.
On Tue, Apr 9, 2019 at 7:26 AM Paul Bicknell < paul@...> wrote: Hi
The larger unites used 5 of the small feet
Another type for the 1/3 units? such as a 432 power
Another type for the 1/2 units? such as a 431 power
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Steve
Sent: 09 April 2019 14:39
To: [email protected]
Subject: [HP-Agilent-Keysight-equipment] Plastic snap-in bottom feet
As I look around the internet at the plastic snap-in bottom feet used on
older HP test equipment, I run into two HP part numbers: 5041-8821 and
5041-9167.
How do the feet differ between the two part numbers? Perhaps color? Or
something else?
Thanks.
Steve, K8JQ
-----
No virus found in this message.
Checked by AVG -
Version: 2016.0.8048 / Virus Database: 4793/15884 - Release Date: 08/14/18
Internal Virus Database is out of date.
|
Correct rack mount bracket?
Is eBay item number:173844545405 the correct rack mounting bracket for my HP-3456A DVM? All these "with handles" and "without handles" descriptions are confusing (if the sellers are even correct).
Jeremy
|
Re: HP 3325A - Help with photos of Option 002 PCB?
I have been looking for the Hi-volt option ( 100v out ) for the Hp 3245A universal source if anyone has information.
That will be a simpler layout that the 3325A? Hi-volt option for it uses a Hi-Volt opamp.
You might look into that design.
George
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Re: HP8340B Attenuator Verification and Cal software
I just spent several hours trying to make a usable copy of the
8340BCAL.imd file from the files section. Constant data errors
reported by ImageDisk, despite spending time reading the
documentation and trying every combination of settings.
If the original disk is available I'm happy to pay for a copy, or
pay a security deposit, make true copies on an HP system, and
return the original.
Steve
On 1/29/2019 6:09 PM, peter bunge
wrote:
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I have 08340-90336 Vol2 and 08340-90307 if they
are any use.?
Are they already in the Files? PeterB
Does anyone have a copy
of the 8340B attenuator calibration and operation
verification test software, part number 08340-10009 they
could share? I¡¯ve tried all the usual places and have been
watching for it on eBay for two years without success.
Thanks in advance,
Steve
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OT: NLS Series MX-1 digital voltmeter
Hi all,
OT, but I'm hoping someone here might know about this little nixie tube voltmeter from Non-Linear Systems in Del Mar, CA I found at my local surplus store while looking through a stack of (mostly badly beat up) HP power supplies. Haven't had much luck finding out anything about it searching the internet. Hoping to acquire manuals if possible.
I cleaned up the switches and tightened the rod that connects the power switch on the front panel to the actual mains switch at the rear of the case, and it works great!
Feel free to just email me directly and allow the topic to fall down the list.
Thanks!
Sean
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Re: HP 3325A - Help with photos of Option 002 PCB?
Yeah, I'm part of that thread. :)
I have got most of the stuff sorted out and cross referenced, I just need to find a source on short RCA cables with right angle plugs on each end.
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Re: HP 3325A - Help with photos of Option 002 PCB?
Hi,
Looks like others are interested in this project too and already cloned this board.
Szabolcs J. L. Trantham < jltran@...> ezt ¨ªrta (id?pont: 2019. ¨¢pr. 4., Cs¨¹ 13:35):
I, too, would like some pictures of Option 002. ? Perhaps they can be posted in the Files section. ? Thanks. ? Joe ? From: [email protected] [mailto:[email protected]] On Behalf Of Jared Cabot
Sent: Thursday, April 04, 2019 5:09 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 3325A - Help with photos of Option 002 PCB? ? That would be awesome if you could take a few good photos. :)
I have a source on the power connectors, and the signal connectors look to be just RCA style, so they should be easy to find too.
I think I'll just make a copy of the HP design (substituting parts where needed) to make it easy to get up and running.
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Re: Plastic snap-in bottom feet
Hi
The larger unites used 5 of the small feet
Another type for the 1/3 units such as a 432 power
Another type for the 1/2 units such as a 431 power
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-----Original Message----- From: [email protected][mailto: [email protected]] On Behalf Of Steve Sent: 09 April 2019 14:39 To: [email protected]Subject: [HP-Agilent-Keysight-equipment] Plastic snap-in bottom feet As I look around the internet at the plastic snap-in bottom feet used on older HP test equipment, I run into two HP part numbers: 5041-8821 and 5041-9167. How do the feet differ between the two part numbers? Perhaps color? Or something else? Thanks. Steve, K8JQ ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2016.0.8048 / Virus Database: 4793/15884 - Release Date: 08/14/18 Internal Virus Database is out of date.
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Jeremy Nichols
Jared Cabot
Paul Bicknell