No I only put the capton tape on there for masking and removed it after the soldering was done , I also tried to improve the thermal interface between the board and the heat spreader including gap pads and copper but its not enough improvement .
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of John Griessen via groups.io Sent: Wednesday, June 1, 2022 4:14 PM To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] OT: Via plugging On 6/1/22 14:41, Lothar baier wrote: the thermal conductivity of solder sucks It's not a big thickness for it to go through though. Maybe your heat up problem is caused by the capton tape? If you can solder to the under side, (maybe with a chisel shaped iron in a metcal heater handle), add a piece of copper thin sheet in a L shape, ( a fin), and it will flow heat away.
|
On 6/1/22 14:41, Lothar baier wrote: the thermal conductivity of solder sucks It's not a big thickness for it to go through though. Maybe your heat up problem is caused by the capton tape? If you can solder to the under side, (maybe with a chisel shaped iron in a metcal heater handle), add a piece of copper thin sheet in a L shape, ( a fin), and it will flow heat away.
|
Btw I don’t think electrical conductivity is a primary concern as the plating of the vias is carrying the main currents , this is mainly about thermal conductivity
?
toggle quoted message
Show quoted text
From: [email protected] < [email protected]>
On Behalf Of Tom Lee via groups.io
Sent: Wednesday, June 1, 2022 3:26 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] OT: Via plugging
?
Well, you don't have too many options at this point, so give it a try. You aren't going to be shipping these, I assume.
The obvious problem to watch out for is the electrical conductivity of the paste. The thermal properties are likely to be roughly similar to those of the standard thermal pastes that are sold specifically for heatsinks. The results may be considered a worse-than-worst-case
test, so if the paste works, you can feel confident that copper-filled vias will work (and better).
In any case, good luck, Lothar!
--Tom
--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
On 6/1/2022 12:59, Lothar baier wrote:
i am working on a circuit board design for a X-Band PA , the part is in a QFN package with a ground slug , i put vias in the ground slug as common for ground and thermal reasons and taped off the vias on the bottom side with capton tape
to minimize? solder wicking ,? the problem however i run into is that the vias are not providing enough thermal conductivity to ensure the die not exceeding the max temperature ratings.?
the apps engineer states that they recommend copper filled vias or using a coin and on the next round i can surely have the vias plugged but i am looking for a solution to salvage the prototype boards and evaluate the impact of plugged vias .
copper paste of course is available and used as a anti seize agent for car repair shops but the question is whether this kind of paste offers sufficient thermal properties and whether there are any concerns using this for a circuit board ?
?
|
Yes those boards are not going anywhere ,? the only options I can think of are finding a wat to plug them or cut out the ground slug and use a small gold plated CuBe plate as a “coin”? although the coin offers the best thermal solution
using this approach can be tricky in a small lab environment with no access to x-ray machines .
?
toggle quoted message
Show quoted text
From: [email protected] < [email protected]>
On Behalf Of Tom Lee via groups.io
Sent: Wednesday, June 1, 2022 3:26 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] OT: Via plugging
?
Well, you don't have too many options at this point, so give it a try. You aren't going to be shipping these, I assume.
The obvious problem to watch out for is the electrical conductivity of the paste. The thermal properties are likely to be roughly similar to those of the standard thermal pastes that are sold specifically for heatsinks. The results may be considered a worse-than-worst-case
test, so if the paste works, you can feel confident that copper-filled vias will work (and better).
In any case, good luck, Lothar!
--Tom
--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
On 6/1/2022 12:59, Lothar baier wrote:
i am working on a circuit board design for a X-Band PA , the part is in a QFN package with a ground slug , i put vias in the ground slug as common for ground and thermal reasons and taped off the vias on the bottom side with capton tape
to minimize? solder wicking ,? the problem however i run into is that the vias are not providing enough thermal conductivity to ensure the die not exceeding the max temperature ratings.?
the apps engineer states that they recommend copper filled vias or using a coin and on the next round i can surely have the vias plugged but i am looking for a solution to salvage the prototype boards and evaluate the impact of plugged vias .
copper paste of course is available and used as a anti seize agent for car repair shops but the question is whether this kind of paste offers sufficient thermal properties and whether there are any concerns using this for a circuit board ?
?
|
There are different types of thermal vias , for this kind the vias are actually filled with copper and then planarized on top , I have a bare EVB that uses this kind of vias and there are no holes only small bumbs on top and bottom , the PCB manufacturer I am using offers this type of via but the extra charge is quite high , if I order 100 boards it only raises the price per board by $1.25 but for proto board it nearly triples the price
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Sergey Kubushyn via groups.io Sent: Wednesday, June 1, 2022 3:24 PM To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] OT: Via plugging On Wed, 1 Jun 2022, Lothar baier wrote: Usually those thermal vias are made something like 12mil diameter and NOT tented on the other side. That makes solder flow all the way into them but not flow out on the other side because of the surface tension. Nothing else is required and it won't do any noticeable difference if done. It is CRITITCAL to have those thermal vias NOT tented on the other side and 10..12mil diameter is also critical to have them wick solder but not let it flow through on the other side. You might get some small bumps on the other side but no solder flow-through. i am working on a circuit board design for a X-Band PA , the part is in a QFN package with a ground slug , i put vias in the ground slug as common for ground and thermal reasons and taped off the vias on the bottom side with capton tape to minimize? solder wicking ,? the problem however i run into is that the vias are not providing enough thermal conductivity to ensure the die not exceeding the max temperature ratings.
the apps engineer states that they recommend copper filled vias or using a coin and on the next round i can surely have the vias plugged but i am looking for a solution to salvage the prototype boards and evaluate the impact of plugged vias .
copper paste of course is available and used as a anti seize agent for car repair shops but the question is whether this kind of paste offers sufficient thermal properties and whether there are any concerns using this for a circuit board ?
--- * * KSI@home KOI8 Net < > The impossible we do immediately. * * Las Vegas NV, USA < > Miracles require 24-hour notice. * *
|
The problem with solder is that the thermal conductivity of solder sucks
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Bruce via groups.io Sent: Wednesday, June 1, 2022 3:11 PM To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] OT: Via plugging Could you fill them with solder without causing problems ??? Perhaps a low melting point solder ? Cheers! Bruce Quoting Lothar baier <Lothar@...>: i am working on a circuit board design for a X-Band PA , the part is
in a QFN package with a ground slug , i put vias in the ground slug as
common for ground and thermal reasons and taped off the vias on the
bottom side with capton tape to minimize? solder wicking ,? the
problem however i run into is that the vias are not providing enough
thermal conductivity to ensure the die not exceeding the max
temperature ratings.
the apps engineer states that they recommend copper filled vias or
using a coin and on the next round i can surely have the vias plugged
but i am looking for a solution to salvage the prototype boards and
evaluate the impact of plugged vias .
copper paste of course is available and used as a anti seize agent for
car repair shops but the question is whether this kind of paste offers
sufficient thermal properties and whether there are any concerns using
this for a circuit board ?
|
Well, you don't have too many options at this point, so give it a
try. You aren't going to be shipping these, I assume.
The obvious problem to watch out for is the electrical conductivity
of the paste. The thermal properties are likely to be roughly
similar to those of the standard thermal pastes that are sold
specifically for heatsinks. The results may be considered a
worse-than-worst-case test, so if the paste works, you can feel
confident that copper-filled vias will work (and better).
In any case, good luck, Lothar!
--Tom
--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
On 6/1/2022 12:59, Lothar baier wrote:
toggle quoted message
Show quoted text
i am working on a circuit board design for a X-Band PA , the part
is in a QFN package with a ground slug , i put vias in the ground
slug as common for ground and thermal reasons and taped off the
vias on the bottom side with capton tape to minimize? solder
wicking ,? the problem however i run into is that the vias are not
providing enough thermal conductivity to ensure the die not
exceeding the max temperature ratings.?
the apps engineer states that they recommend copper filled vias or
using a coin and on the next round i can surely have the vias
plugged but i am looking for a solution to salvage the prototype
boards and evaluate the impact of plugged vias .
copper paste of course is available and used as a anti seize agent
for car repair shops but the question is whether this kind of
paste offers sufficient thermal properties and whether there are
any concerns using this for a circuit board ?
|
Re: HP 8510B Service manual CLIP
I do have the 8510A schematics and I have tried to work with these. Power seems to be unchanged from 85101A to 85101B, but there seem to be a lot of changes in the digital cage.
Obviously, as already mentioned the bubble memory got replaced by EEPROM.
But as far as I could see, also the processor got an update.
And the IO card definitely uses different chips. So, no chance with the A schematics.
Best regards,
Tom DG8SAQ
|
On Wed, 1 Jun 2022, Lothar baier wrote: Usually those thermal vias are made something like 12mil diameter and NOT tented on the other side. That makes solder flow all the way into them but not flow out on the other side because of the surface tension. Nothing else is required and it won't do any noticeable difference if done. It is CRITITCAL to have those thermal vias NOT tented on the other side and 10..12mil diameter is also critical to have them wick solder but not let it flow through on the other side. You might get some small bumps on the other side but no solder flow-through. i am working on a circuit board design for a X-Band PA , the part is in a QFN package with a ground slug , i put vias in the ground slug as common for ground and thermal reasons and taped off the vias on the bottom side with capton tape to minimize? solder wicking ,? the problem however i run into is that the vias are not providing enough thermal conductivity to ensure the die not exceeding the max temperature ratings.
the apps engineer states that they recommend copper filled vias or using a coin and on the next round i can surely have the vias plugged but i am looking for a solution to salvage the prototype boards and evaluate the impact of plugged vias .
copper paste of course is available and used as a anti seize agent for car repair shops but the question is whether this kind of paste offers sufficient thermal properties and whether there are any concerns using this for a circuit board ?
--- * * KSI@home KOI8 Net < > The impossible we do immediately. * * Las Vegas NV, USA < > Miracles require 24-hour notice. * *
|
Could you fill them with solder without causing problems ???
Perhaps a low melting point solder ?
Cheers!
Bruce
Quoting Lothar baier <Lothar@...>:
toggle quoted message
Show quoted text
i am working on a circuit board design for a X-Band PA , the part is in a QFN package with a ground slug , i put vias in the ground slug as common for ground and thermal reasons and taped off the vias on the bottom side with capton tape to minimize? solder wicking ,? the problem however i run into is that the vias are not providing enough thermal conductivity to ensure the die not exceeding the max temperature ratings.
the apps engineer states that they recommend copper filled vias or using a coin and on the next round i can surely have the vias plugged but i am looking for a solution to salvage the prototype boards and evaluate the impact of plugged vias .
copper paste of course is available and used as a anti seize agent for car repair shops but the question is whether this kind of paste offers sufficient thermal properties and whether there are any concerns using this for a circuit board ?
|
i am working on a circuit board design for a X-Band PA , the part is in a QFN package with a ground slug , i put vias in the ground slug as common for ground and thermal reasons and taped off the vias on the bottom side with capton tape to minimize? solder wicking ,? the problem however i run into is that the vias are not providing enough thermal conductivity to ensure the die not exceeding the max temperature ratings.?
the apps engineer states that they recommend copper filled vias or using a coin and on the next round i can surely have the vias plugged but i am looking for a solution to salvage the prototype boards and evaluate the impact of plugged vias .
copper paste of course is available and used as a anti seize agent for car repair shops but the question is whether this kind of paste offers sufficient thermal properties and whether there are any concerns using this for a circuit board ?
|
They Lack ground conductivity and seismic protection.
|
Re: HP 8510B Service manual CLIP
I have a paper manual set for the 8510A - it covers both the 85101A and the 85102A - the 85102B as at most 3 differences depending on the particular model (either 1 or 3 cards are needed to convert an 85102A to a B version).
I have never looked for schematics particular to the replaced cards, but would be interested to know if anyone has them.
Major difference between the 85101A and B versions (as far as I know) is the exchange of bubble memory for e-prom memory (for the OS).
If anyone has any component level information about these cards, it would be a good idea to get it archived.
ANYONE HAVE ANYTHING - Updates to the 8510A CLIPs ????
Cheers!
Bruce
Quoting Lothar baier <Lothar@...>:
toggle quoted message
Show quoted text
Are you sure ? all of the schematics that were available for the A I ever seen covered the 85102A part only and not the 85101 display only
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Bruce via groups.io
Sent: Wednesday, June 1, 2022 12:18 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 8510B Service manual CLIP
There is much similarity between the A and B versions. The schematics for the A are available. Can you work from that?
Cheers!
Bruce
Quoting "tom_iphi via groups.io" <iphi@...>:
Hi folks,
I have a broken 8510B display section that I'm trying to fix and I
have been chasing a schematic for a long time.
Has anyone spotted the mentioned B-supplement?
I know those display sections are said to be dirt cheap, but not so on
this side of the gread pond (Germany).
Wayne,
would you please share your reverse engineering results with me? I'd
highly appreciate it.
This could help a lot with my repair efforts.
Thanks and best regards,
Tom
|
Re: HP 8510B Service manual CLIP
Quoting Lothar baier <Lothar@...>:
toggle quoted message
Show quoted text
Are you sure ? all of the schematics that were available for the A I ever seen covered the 85102A part only and not the 85101 display only
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Bruce via groups.io
Sent: Wednesday, June 1, 2022 12:18 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 8510B Service manual CLIP
There is much similarity between the A and B versions. The schematics for the A are available. Can you work from that?
Cheers!
Bruce
Quoting "tom_iphi via groups.io" <iphi@...>:
Hi folks,
I have a broken 8510B display section that I'm trying to fix and I
have been chasing a schematic for a long time.
Has anyone spotted the mentioned B-supplement?
I know those display sections are said to be dirt cheap, but not so on
this side of the gread pond (Germany).
Wayne,
would you please share your reverse engineering results with me? I'd
highly appreciate it.
This could help a lot with my repair efforts.
Thanks and best regards,
Tom
|
And if you find you need more U unit space, stack your lack.
|
Re: HP 8510B Service manual CLIP
Are you sure ? all of the schematics that were available for the A I ever seen covered the 85102A part only and not the 85101 display only
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Bruce via groups.io Sent: Wednesday, June 1, 2022 12:18 PM To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] HP 8510B Service manual CLIP There is much similarity between the A and B versions. The schematics for the A are available. Can you work from that? Cheers! Bruce Quoting "tom_iphi via groups.io" <iphi@...>: Hi folks,
I have a broken 8510B display section that I'm trying to fix and I
have been chasing a schematic for a long time.
Has anyone spotted the mentioned B-supplement?
I know those display sections are said to be dirt cheap, but not so on
this side of the gread pond (Germany).
Wayne,
would you please share your reverse engineering results with me? I'd
highly appreciate it.
This could help a lot with my repair efforts.
Thanks and best regards,
Tom
|
Re: E4407B strange peak shapes at low RBW
Hi Sandra,
What is a NSCOM reset?
Do you mean factory reset / preset on the machine itself or some command?
|
Re: HP 8510B Service manual CLIP
There is much similarity between the A and B versions. The schematics for the A are available. Can you work from that?
Cheers!
Bruce
Quoting "tom_iphi via groups.io" <iphi@...>:
toggle quoted message
Show quoted text
Hi folks,
I have a broken 8510B display section that I'm trying to fix and I have been chasing a schematic for a long time.
Has anyone spotted the mentioned B-supplement?
I know those display sections are said to be dirt cheap, but not so on this side of the gread pond (Germany).
Wayne,
would you please share your reverse engineering results with me? I'd highly appreciate it.
This could help a lot with my repair efforts.
Thanks and best regards,
Tom
|
Re: E4407B strange peak shapes at low RBW
The problem isn’t exactly new ,? back when the ESG generators came out we had to buy a bunch of equipment including a 89440A and E4419B because the service software only supported those and actually did a IDN to ensure that the right equipment
was there ,? if I remember correctly you also had to have all the equipment connected and turned on even if you did a sub test that didn’t require all the equipment !
Effectively this gives agilent full control over the service life of their equipment and who is servicing them , by limiting the access to only a few big labs the small independent labs are shut out as much as individual users so the big
guys can charge exorbitant $?
Case in point is that eventually indididuals wont be able to mess with later model equipment because even if you manage to find and repair the problem you wont be able to do the adjustments
?
?
?
?
toggle quoted message
Show quoted text
From: [email protected] < [email protected]>
On Behalf Of Richard Parrish via groups.io
Sent: Wednesday, June 1, 2022 11:40 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] E4407B strange peak shapes at low RBW
?
Keysight will no longer sell the licenses for the N7800A unless you are a large company and want to do your own calibrations but the catch is that you HAVE to use the equipment that's written into
the software.? It is a required list of equipment, not a suggested list which leaves all but a very rare few who are able to do that. ? The cost of the required equipment, just the minimum runs about $100K "used" and that will allow you to do only a limited
calibration on most pieces of equipment. ? Everything these days is in software and very little can be done manually anymore due to the use of A/D's and D/A's and signal processing.? Those allow for great specs but at the expense of allowing for manual calibrations.
You pretty?much have to make the decision of whether or not you need what the later generation equipment can give you or do you want the ability to be able to do your own calibrations.? Of course
cost is a huge consideration also.
I pretty much designed my lab around the ability to do the repairs and adjustments myself and have been happy with that decision.? There's a LOT of good equipment out there.
HP used discrete filters for the IF filters , those filters are constructed using multiple poles that are coupled and each pole is adjusted individually to form a specific
filter shape and bandwidth as a result if one pole is off than you get a funny shape like the one you are seeing !
On the older analyzers (855x, 8566/68, 70K, 8590…..? the adjustments were done manually , you needed to build of some shorting clips or cables and follow the instructions
on the manual and usually this worked quite well .
However on the later model analyzers HP switched from manual adjustments and performance tests and providing HP basic test/alignment software free of charge to using a integrated
test environment (N7800A )? with individual test modules for each analyzer family (N7811A for the ESA Series )? , this software requires a paid license however !? I am not aware of any alternate ways to do the adjustments however richard is the authority on
this and he might know
?
?
Hi
Are you using an external test signal?-it seems so.
First i would make a self alignment with the inbuildt? 50 Mhz cal signal.
Hardy
?
?
You will need to go in and adjust your Xtal and LC filters.? Not hard, just a pain.
|
toggle quoted message
Show quoted text
From: [email protected] < [email protected]>
On Behalf Of nigel adams via groups.io
Sent: Saturday, May 28, 2022 2:05 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP8640B no rf out
?
A very similar style of these ‘finger’ contact is found in the 8011/12/13 pulse generators which can be found quite cheaply…. How do i know… just repaired one… works lovely.
On 28 May 2022, at 22:01, n4buq <n4buq@...> wrote:
?
Other HP switches use those wipers.? I think some of the slide switches on the 8640B use them but I think there are others too.
From:
"Donald Prins" <dyhprins@...>
To: "HP-Agilent-Keysight-equipment" <[email protected]>
Sent: Saturday, May 28, 2022 10:06:01 AM
Subject: Re: [HP-Agilent-Keysight-equipment] HP8640B no rf out
Hi Ellud,
Can you tell me where one can obtain those wipers? I have a HP8640B that is missing 3 in total on the FM/RANGE switches. Your help will be much appreciated.
Donald?
PE1AHJ
|
Sergey Kubushyn
RFI-EMI-GUY