Re: I'm old 70+, the 70K system is old; good or bad omen?
Perhaps, it is a cult, but I don't think so. Cult-ship usually implies a blind following of a personality. ESR meter users are just happy that the instruments cut a lot of time and effort out of repairs. Failed capacitors usually have very obvious ESR signatures: 10 to 1000x the expected ESR. If you are looking at 1.5 ohm measured ESR vs 1.25 ohm, expected ESR, as a sign of a failed capacitor, you are using the ESR meter wrongly. Capacitors have to get really bad before the circuitry will fail, in most cases. The dissipation factor is very useful for designing a power supply, but a bit awkward to use for repair purposes. Most meters that read DF need the capacitor out of circuit to give any sort of useful reading. ESR meters measure at such a low voltage that the semiconductor part of the circuit is not activated. The other thing I notice is the ESR meters generally work at 50KHz, but bridges that measure DF are mostly 1KHz. 50KHz measurements usually mean a lot more to me when I am repairing switching power supplies, than does 1KHz. -Chuck Harris On Wed, 24 Nov 2021 18:44:14 -0500 "Dave McGuire" <mcguire@...> wrote: On 11/24/21 6:40 PM, Richard Knoppow wrote:
?? It may prove more useful to use dissipation factor rather than
ESR even though both are a measure of the same thing. Since DF is a
ratio of reactance to resistance it varies with frequency and may
be more indicative of capacitor quality than plain ESR.
?? There is a good, short article on DF at:
<> You know, I keep telling people that, and people keep telling me
I'm crazy. All converting DF to ESR does is introduce a frequency
dependency that gets in the way of deciding "good capacitor" or "bad
capacitor". There's almost a "cult of ESR" these days, it seems.
-Dave
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Re: 8341A *restoration adventure*
RubinRubio-
Nicely done - looks good.
Some advice on the fan. It should spin extremely easily. I generally disassemble the fan and clean the "post" that it spins on. If you do this (I advise that you do), be sure to clean not only the ost but also the shoulders of the post and the bushings that ride on the shoulders. Use a very little quantity of very light oil.
You may also want to start looking for the 2-7GHz amp as that is what drives the sytm for frequencies above 2 Ghz - based on your measurements, its output seems marginal or low.
If you haven't don so already, you may want to measure the AC ripple on each of the supplies.
So far, so good!
Cheers!
Bruce
Quoting RubenRubio <rubenrb2019@...>:
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Hello there!
While waiting for the arrival of parts, I spent some time cleaning and checking some parts, specifically keyboard, display, fan and panels.
Disassemble bit by bit and brushing non-electrical parts with hot water, scouring pad and dish cleaner, and pcb with toothbrush and compressed air. Also lubricate the encoder axle, and spray some contact cleaner in the key gold pads. A lot of bits as you can see in the photos. Be *extremely careful* with keyboard frame, made of casted aluminium: softer material ever, easily breakable. My worst enemy: fossilized cal stickers.
When I dismantled the fan housing, I noticed that almost every screw are loose, because vibrations through the years. Very dirty parts, especially the fan itself, with dark dust everywhere. Now they are clean and firmly mounted.
After the?disassembly and assembly, fifth column in the entry display still off. I've found in the service manual a procedure to troubleshoot this board (alpha column drivers in the display driver board). Maybe a transistor are open, or the pull-up/feed resistor arrays. I'll check this in the next days.
And last but not least: I managed to change the main line voltage selector to run the unit with 230VAC. It is weird, because the 230VAC cam position doesn't do anything, even standby, but the 240VAC (the last) position allows the unit to start without issues. I readed in the manual that both positions are ok for my local voltage (230 Vrms), so no problems I hope. Maybe the 230VAC position has no transformer winding connected, because I aplied contact cleaner inside the selector, but still nothing. And a final question:?Is it possible for the pass transistors in the back to get hotter if the unit is powered at 230 than at 120?
Best regards,
R.
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Re: 8341A *restoration adventure*
Hello there!
While waiting for the arrival of parts, I spent some time cleaning and checking some parts, specifically keyboard, display, fan and panels.?
Disassemble bit by bit and brushing non-electrical parts with hot water, scouring pad and dish cleaner, and pcb with toothbrush and compressed air. Also lubricate the encoder axle, and spray some contact cleaner in the key gold pads. A lot of bits as you can see in the photos. Be extremely careful with keyboard frame, made of casted aluminium: softer material ever, easily breakable. My worst enemy: fossilized cal stickers.
?
When I dismantled the fan housing, I noticed that almost every screw are loose, because vibrations through the years. Very dirty parts, especially the fan itself, with dark dust everywhere. Now they are clean and firmly mounted.
After the?disassembly and assembly, fifth column in the entry display still off. I've found in the service manual a procedure to troubleshoot this board (alpha column drivers in the display driver board). Maybe a transistor are open, or the pull-up/feed resistor arrays. I'll check this in the next days.
And last but not least: I managed to change the main line voltage selector to run the unit with 230VAC. It is weird, because the 230VAC cam position doesn't do anything, even standby, but the 240VAC (the last) position allows the unit to start without issues. I readed in the manual that both positions are ok for my local voltage (230 Vrms), so no problems I hope. Maybe the 230VAC position has no transformer winding connected, because I aplied contact cleaner inside the selector, but still nothing. And a final question:?Is it possible for the pass transistors in the back to get hotter if the unit is powered at 230 than at 120??
Best regards,
R.
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HP 35665A - Enable all options
Apparently can this be done by programming some magic data into an EEPROM and replacing the one in the unit. Before I do so, I would like to check if there is an easier way?
I guess it is the 5V?24C01C?
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Re: HP 5960-7083 70340A/70341A Signal Generators Calibration Guide
Hi all please disregard the message? as we have it on the hp 70000 site??
It got missed as the part number does not have the model number in it??
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HP 5960-7083 70340A/70341A Signal Generators Calibration Guide
Hi all a member has informed me about?
HP 5960-7083 70340A/70341A Signal Generators Calibration Guide
being available on Ebay?
I believe there is no PDF available for this manual? so could someone in the USA passably get the manual and arrange for it to be scanned?
as postage to the UK will cost more than within the USA
Regards Paul?
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Re: 8753ES Source module schematic
Hi Vladan… ? Pin 14 reads about 4.5 Ohms to ground. I have another Source module for comparison that reads a bout 1.5K. Now working on how to determine shorted part. Have eliminated the attenuator, Oscillator, and YIG, as it still reads ‘shorted’ with the board completely removed from the assembly. I suspect that Tantalum (looks like 10 uF) but there seems to be an electrolytic of 3.5 uF in that circuit also, but haven’t confirmed. Anyway, it’s late here so calling it a night. Thanks for your help so far; that Pin 14 pointer helped a lot. ? Tom. ?
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From: [email protected] <[email protected]> On Behalf Of pianovt via groups.io
Sent: Wednesday, November 24, 2021 9:56 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] 8753ES Source module schematic? I am looking at a source module as I write. I am not sure if 22V goes anywhere else in the instrument, but on the source it connects to pin 14 of P1 (that long brown AMP connector that attaches to the mother board). From there it goes through a filter and then to various places.
- One of those places is the DIP connector for the ribbon cable to the step attenuator. It's next to the 20W resistor. Be careful to not bend the resistor, it can lead to a board failure. Disconnect that ribbon and see if it's the attenuator that's drawing the current.
- The power supply filter I mentioned above consists of:
????????????? A small capacitor to ground (0.1uF, smt), it's on the bottom side of the board.
????????????? A series coil (toroid with many turns in a plastic base, near the middle of the 20W resistor). I doubt this coil is the problem.
????????????? A yellow 10uF SMT tantalum capacitor near the Q16 TO220 transistor with the heat sink. It's the SMT capacitor under the attenuator bracket, near the tip of the heat sink.
If the above are all OK, completely detach the circuit board from the rest and check the resistance from pin 14 on the AMP connector to ground.The circuit board has several sockets that bring power, etc. to the microcircuit housing below. WHen you detach the board from the housing, you are checking if the problem is with one of the microcircuits.
If none of this works, let me know and I will look closer.
Vladan
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Re: 8753ES Source module schematic
Got it. Thanks. Will report back when I see what’s what in that area. ?
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From: [email protected] <[email protected]> On Behalf Of pianovt via groups.io
Sent: Wednesday, November 24, 2021 9:56 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] 8753ES Source module schematic? I am looking at a source module as I write. I am not sure if 22V goes anywhere else in the instrument, but on the source it connects to pin 14 of P1 (that long brown AMP connector that attaches to the mother board). From there it goes through a filter and then to various places.
- One of those places is the DIP connector for the ribbon cable to the step attenuator. It's next to the 20W resistor. Be careful to not bend the resistor, it can lead to a board failure. Disconnect that ribbon and see if it's the attenuator that's drawing the current.
- The power supply filter I mentioned above consists of:
????????????? A small capacitor to ground (0.1uF, smt), it's on the bottom side of the board.
????????????? A series coil (toroid with many turns in a plastic base, near the middle of the 20W resistor). I doubt this coil is the problem.
????????????? A yellow 10uF SMT tantalum capacitor near the Q16 TO220 transistor with the heat sink. It's the SMT capacitor under the attenuator bracket, near the tip of the heat sink.
If the above are all OK, completely detach the circuit board from the rest and check the resistance from pin 14 on the AMP connector to ground.The circuit board has several sockets that bring power, etc. to the microcircuit housing below. WHen you detach the board from the housing, you are checking if the problem is with one of the microcircuits.
If none of this works, let me know and I will look closer.
Vladan
|
Re: 8753ES Source module schematic
I am looking at a source module as I write. I am not sure if 22V goes anywhere else in the instrument, but on the source it connects to pin 14 of P1 (that long brown AMP connector that attaches to the mother board). From there it goes through a filter and then to various places.
- One of those places is the DIP connector for the ribbon cable to the step attenuator. It's next to the 20W resistor. Be careful to not bend the resistor, it can lead to a board failure. Disconnect that ribbon and see if it's the attenuator that's drawing the current.
- The power supply filter I mentioned above consists of:
????????????? A small capacitor to ground (0.1uF, smt), it's on the bottom side of the board.
????????????? A series coil (toroid with many turns in a plastic base, near the middle of the 20W resistor). I doubt this coil is the problem.
????????????? A yellow 10uF SMT tantalum capacitor near the Q16 TO220 transistor with the heat sink. It's the SMT capacitor under the attenuator bracket, near the tip of the heat sink.
If the above are all OK, completely detach the circuit board from the rest and check the resistance from pin 14 on the AMP connector to ground.The circuit board has several sockets that bring power, etc. to the microcircuit housing below. WHen you detach the board from the housing, you are checking if the problem is with one of the microcircuits.
If none of this works, let me know and I will look closer.
Vladan
|
Re: I'm old 70+, the 70K system is old; good or bad omen?
Thanks Richard and agreed... off to theta land
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-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Richard Knoppow Sent: Wednesday, November 24, 2021 3:41 PM To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] I'm old 70+, the 70K system is old; good or bad omen? It may prove more useful to use dissipation factor rather than ESR even though both are a measure of the same thing. Since DF is a ratio of reactance to resistance it varies with frequency and may be more indicative of capacitor quality than plain ESR. There is a good, short article on DF at: <> On 11/24/2021 3:05 PM, Gene Silvernail wrote: Church Roger that,
The thing that helped me down the wrong path is the hybrid package.
Electrically it's radial, mechanical is axial...something new for me.
After extracting my head I re-ran cap and ESR readings. Capacitance is
within range when run at 1khz and drops off at
10 and 100 khz. ESR is around around 1 ohm at 1 khz where it goes over
range on 10 and 100 khz, meaning way high for ESR numbers. Today,
SMPS's run much faster extending in MHz. So lower Z and R Caps were
needed...so how good of a ESR number is needed at 40 kHz?...So...
All readings would be good if operating below 1kHz, which they aren't.
They don't even make 10kHz so...
Conclusionis they're shot and will replace...
Has anyone ever measured 10 or 100 kHz ESR on any of originals that
were still working,
Thanks all the your help
Gene/K7QHO
Sent from my T-Mobile 5G Device
Get Outlook for Android <>
-----------------------------------------------------------------
*From:* [email protected]
<[email protected]> on behalf of Dave McGuire
<mcguire@...>
*Sent:* Wednesday, November 24, 2021 6:57:38 AM
*To:* [email protected]
<[email protected]>
*Subject:* Re: [HP-Agilent-Keysight-equipment] I'm old 70+, the 70K
system is old; good or bad omen?
On 11/24/21 7:38 AM, Chuck Harris wrote:
Depending on the manufacturer, the lead arrangement had another more
practical purpose, it made capacitor orientation irrelevant.
The outer leads were welded to the aluminum can, and were by
convention the negative leads. The inner lead was positive.
It is virtually always the case with radial leaded aluminum
electrolytic capacitors that the outer most lead(s) will be the
negative lead, and the most central lead(s) the positive.
There were some tantalum caps in a similar package that were all
doubles, as I recall. I forgot to mention this. The capacitors in question here look
like typical cylindrical Al electrolytics, but they have a third lead
coming out from the *top* of the Al can. See the datasheet for the
Vishay/Sprague 672D series.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
-- Richard Knoppow dickburk@... WB6KBL
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Re: HP 8640B - internal counter suddenly got crazy
Hi Jerry – ? I have some 8640B “hangar queens” in the basement. I can probably help you with another internal oscillator. 73 – and Happy Thanksgiving – Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ?
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From: [email protected] < [email protected]> On Behalf Of Jerry Meyerhoff, JDM LABS Sent: Wednesday, November 24, 2021 4:24 PM To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] HP 8640B - internal counter suddenly got crazy ? HI Dave, Mike and Frank. Another case of FRTM? first read the manual?? page 22 of 247.? 5 mc
Not sure why I thought it was 10 mc but that was a canned oscillator I had? .. Well that was quick & easy . Thanks a mil' !!!? Appreciate your kind patience ..
Next I'll have to post a ? on output attenuator missing / intermittant on some level steps along with level meter not reading .Or maybe 1st look in FAQ's .. <wink>
Happy Thanksgiving !?
--
Cheers Jerry? WA9FIY?? 11.24.2021
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Re: 8753ES Source module schematic
Yes, the +22. On the post-regulator board the light labeled +22 is out, even when the rest of the LEDs are flashing. When I remove the source module, all is well with the LEDs. Removing the other boards per the manual procedure didn’t change the flashing LED pattern. Given what I have been able to deduce from the manual, the Source module appears to be the only circuit that uses +22. ? Thanks. ?
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From: [email protected] <[email protected]> On Behalf Of pianovt via groups.io
Sent: Wednesday, November 24, 2021 8:55 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] 8753ES Source module schematic? Can you tell which power supply is being overloaded?
Vladan
|
Re: 8753ES Source module schematic
Can you tell which power supply is being overloaded?
Vladan
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8753ES Source module schematic
Other than one that Vladan posted a few years back of the YIG circuit pinout, has anyone ever found or created a schematic or
even just the pinout for one of those modules? The one I have just started drawing too much current, so the power supplies
won't completely fire up. I'd like to try to hook it up external to the Net An to troubleshoot it. I am hoping that it is
just an electrolytic that has decided to become too leaky or maybe open, although have not seen any damage. Could wholesale
change out as many as possible but would learn more with a schematic or at least the pinout.
Thanks for any thoughts, in advance. Or a priori?
Tom Holmes, N8ZM
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Re: 70900A Artek CLIP Manual
On 11/24/21 7:40 PM, pianovt via groups.io wrote: I'll give you a rough idea when you fix the thing!
Vladan / Vladen / Bladen soda -> keyboard -- Dave McGuire, AK4HZ New Kensington, PA
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Re: I'm old 70+, the 70K system is old; good or bad omen?
On 11/24/21 7:34 PM, Gene Silvernail wrote: Couldn't agree more DF tan theta are more useful for me. In this case, readings I got on the 70900A caps, theta speaks loudly of the dielectric absorption with increased frequency and plummeting capacitance.
With the typical PS schematic provided, I believe by Vladen, I get it finally that what's being piped around is 40kHz power. That provided schematic turned the lights on for me...many thanks.
Modules then rectify and filtering is all by way of subject caps from a bridge arrangement...so the caps must handle effectively 80 kHz ripple that me thinks may be far from sinusoidal 80kHZ x n. Yup. I don't know how harmonically impure that 40kHz sine wave is, but there probably wasn't much motivation to make it perfect. With the big changes I'm seeing in theta with increasing f, very little cap is left after these caps heat up and deteriorate with service life. Heat is the big issue. You see how packed things are in the 70900, and heat is the biggest enemy of capacitors' life expectancy. Couldn't agree more that probably any quality 105 cap is probably an improvement over these ancients. I don't know if it's fair to call them "ancients", good heavens. It's not at all common for capacitors of HP 70K age in general to drop like flies. Twenty years older, yes, but not these. Here we...rock n roll Indeed, we most certainly do. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: 70900A Artek CLIP Manual
Thanks Paul, I dropped Dave a line… ?
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From: [email protected] <[email protected]> On Behalf Of Paul Bicknell
Sent: Wednesday, November 24, 2021 11:10 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] 70900A Artek CLIP Manual? Hi all ? Just a bit of information the list below is not the complete list of the CLIP drawings for the 70900A as it comes in 2 large folders volumes 2 & 3 this is the same arrangement for the 70900B basically a lot of paper work The complete list can be found in the 70900A service manual Volume 1 on page XVI in the Files on the groups IO HP 70000 Please note? there is a duplication of Part numbers? 70900-60003 is the part number for the power supply Schematic / circuit diagram? the same number is on the power supply component location Drawing ? I do not have the Artek clip for the 70900A as it was not available when I started and I was fortunate to find an original set of drawings But I do have the 70900B Artek Clip and that has the power supply Schematic / circuit diagram and the power supply component location Drawing ? Suggest you give Dave at Artek a call / Email and he will sort it out for you ? So I hope this helps Regards Paul ? ? ? Working on the PS board of the 70900A and bought the CLIP from Artek. Beautifully clear images, excellent for what's there. Unfortunately, the one thing I really needed it for isn't, that being the PS board. Anyone have any idea where that would that be found? Any help is greatly appreciated.
Pre-Thanks
Gene/K7QHO
|
Re: 70900A Artek CLIP Manual
I'll give you a rough idea when you fix the thing!
Vladan / Vladen / Bladen
|
Re: I'm old 70+, the 70K system is old; good or bad omen?
Couldn't agree more DF tan theta are more useful for me. In this case, readings I got on the 70900A caps, theta speaks loudly of the dielectric absorption with increased frequency and plummeting capacitance. ? With the typical PS schematic provided, I believe by Vladen, I get it finally that what's being piped around is 40kHz power. That provided schematic turned the lights on for me...many thanks. ? Modules then rectify and filtering is all by way of subject caps from a bridge arrangement...so the caps must handle effectively 80 kHz ripple that me thinks may be far from sinusoidal 80kHZ x n. ? With the big changes I'm seeing in theta with increasing f, very little cap is left after these caps heat up and deteriorate with service life. ? Couldn't agree more that probably any quality 105 cap is probably an improvement over these ancients. ? Here we...rock n roll ?
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-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Dave McGuire
Sent: Wednesday, November 24, 2021 3:44 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] I'm old 70+, the 70K system is old; good or bad omen? ? On 11/24/21 6:40 PM, Richard Knoppow wrote: >? ?? It may prove more useful to use dissipation factor rather than ESR > even though both are a measure of the same thing. Since DF is a ratio > of reactance to resistance it varies with frequency and may be more > indicative of capacitor quality than plain ESR. >? ?? There is a good, short article on DF at: > <> ? ?? You know, I keep telling people that, and people keep telling me I'm crazy.? All converting DF to ESR does is introduce a frequency dependency that gets in the way of deciding "good capacitor" or "bad capacitor".? There's almost a "cult of ESR" these days, it seems. ? ???????????? -Dave ? -- Dave McGuire, AK4HZ New Kensington, PA ? ? ? ?
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Re: 70900A Artek CLIP Manual
Damn....VLADEN...I'll get it right yet...
Sent from my T-Mobile 5G Device
Get
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Darn spell check sorry VLADAN
Sent from my T-Mobile 5G Device
Get
From: Gene Silvernail <genesilvernail@...>
Sent: Wednesday, November 24, 2021 3:25:46 PM
To: [email protected] <[email protected]>
Subject: Re: [HP-Agilent-Keysight-equipment] 70900A Artek CLIP Manual
?
Bladen I gotta know...where did it live?
Sent from my T-Mobile 5G Device
Get
Hi all
?
Just a bit of information the list below is not the complete list of the CLIP drawings for the 70900A as it comes in 2 large folders volumes 2 & 3 this
is the same arrangement for the 70900B basically a lot of paper work
The complete list can be found in the 70900A service manual Volume 1 on page XVI in the Files on the groups IO HP 70000
Please note? there is a duplication of Part numbers? 70900-60003 is the part number for the
power supply Schematic / circuit diagram? the same number is on the power supply component location Drawing
?
I do not have the Artek clip for the 70900A as it was not available when I started and I was fortunate to find an original set of drawings
But I do have the 70900B Artek Clip and that has the power supply Schematic / circuit diagram and the power supply component location Drawing
?
Suggest you give Dave at Artek a call / Email and he will sort it out for you
?
So I hope this helps Regards Paul
?
?
?
Working on the PS board of the 70900A and bought the CLIP from Artek. Beautifully clear images, excellent for what's there. Unfortunately, the one thing I really needed it for isn't, that being the PS board. Anyone have any idea where
that would that be found? Any help is greatly appreciated.
Pre-Thanks
Gene/K7QHO
|
RubenRubio
Anders
Paul Bicknell
Dave McGuire