On Mar 2, 2022, at 12:01 AM, Lothar baier <Lothar@...> wrote:

? Not surprised at all ! Virtually all “NI”

GPIB/USB adapters sold by Chinese vendors on ebay are Fake , unfortunately this also starts to spill over on US sellers as people who bought them from china and couldn’t get them to work are selling them again on ebay !

The best thing you can do is buy from a US seller a unit that is new in box , you can also check the unit to see if it has the little white barcode serial number label on it and run the serial number by NI?

On Mar 2, 2022, at 00:00, Lou Blasco via groups.io <vk3alb@...> wrote:

?

Interesting Dave,

You must have installed NI drivers to get it to work. What version are you using?

Regards

Lou
VK3ALB

On 2/03/2022 16:47, Dave Miller wrote:

I purchased recently from EBL2018 on a NI USB HS and it seemed to recognize fine on time labs.
I can’t say 100% that I did anything else other than plugging it in and seeing software found it   FWIW. It looks exactly like the one I purchased from NI a few years ago. 

Dave
VE7HR 

On Mar 1, 2022, at 9:43 PM, Lou Blasco <vk3alb@...> wrote:

?Thanks All,

It probably won't surprise you as much as it disappointed me to learn that I bought a fake adapter from eBay. The seller gave me all my money back in a heartbeat as soon as I lodged a complaint so I guess he had an idea of what he was doing. 

-- 
Regards

Lou
VK3ALB

On Mar 2, 2022, at 00:42, Matt Huszagh via groups.io <huszaghmatt@...> wrote:

?What’s the test set and does it provide any reason why it requires a newer serial number source? I had a compatibility issue with my 8341 and 8510C but it was firmware related and simply fixed by flashing newer firmware (I believe it needed the April ‘92 though I can check to be sure if you’d like to know). I have a copy of this firmware but you can also download it from ko4bb (FYI I found the 8340 and 8341 firmware to be identical). If there are actual hardware changes needed I’d be curious to hear this too.

?Matt

On Mar 2, 2022, at 00:00, Lou Blasco via groups.io <vk3alb@...> wrote:

?

Interesting Dave,

You must have installed NI drivers to get it to work. What version are you using?

Regards

Lou
VK3ALB

On 2/03/2022 16:47, Dave Miller wrote:

I purchased recently from EBL2018 on a NI USB HS and it seemed to recognize fine on time labs.
I can’t say 100% that I did anything else other than plugging it in and seeing software found it   FWIW. It looks exactly like the one I purchased from NI a few years ago. 

Dave
VE7HR 

On Mar 1, 2022, at 9:43 PM, Lou Blasco <vk3alb@...> wrote:

?Thanks All,

It probably won't surprise you as much as it disappointed me to learn that I bought a fake adapter from eBay. The seller gave me all my money back in a heartbeat as soon as I lodged a complaint so I guess he had an idea of what he was doing. 

-- 
Regards

Lou
VK3ALB

I purchased recently from EBL2018 on a NI USB HS and it seemed to recognize fine on time labs.
I can’t say 100% that I did anything else other than plugging it in and seeing software found it   FWIW. It looks exactly like the one I purchased from NI a few years ago. 

Dave
VE7HR 

On Mar 1, 2022, at 9:43 PM, Lou Blasco <vk3alb@...> wrote:

?Thanks All,

It probably won't surprise you as much as it disappointed me to learn that I bought a fake adapter from eBay. The seller gave me all my money back in a heartbeat as soon as I lodged a complaint so I guess he had an idea of what he was doing. 

-- 
Regards

Lou
VK3ALB

On Mar 1, 2022, at 9:43 PM, Lou Blasco <vk3alb@...> wrote:

?Thanks All,

It probably won't surprise you as much as it disappointed me to learn that I bought a fake adapter from eBay. The seller gave me all my money back in a heartbeat as soon as I lodged a complaint so I guess he had an idea of what he was doing.

--
Regards

Lou
VK3ALB

Ok.? Just wondering because it seems whenever I need one, all I have is the other!? So tempting to just turn it upside down....

Jim

Sent from my T-Mobile 4G LTE Device

-------- Original message --------

From: 搁别苍é别 <k6fsb.1@...>

Date: 3/1/22 2:30 PM (GMT-08:00)

To: [email protected]

Subject: Re: [HP-Agilent-Keysight-equipment] HP8640B RF Fails Several Seconds After Power Up

works for me, although seems the condensation is worse with canned air, may be my imagination.
搁别苍é别

On 3/1/22 12:42 PM, Jim Ford wrote:

Say, anybody know any disadvantages of using freeze spray as a duster or a duster as freeze spray?? Turn one upside-down to make it work as the other, of course.? TIA.

Thanks for all the tips, guys; really helpful.
I've found a very readable and comprehensible description of the various functional blocks concerned and how they inter-relate to one another in the Analog Troubleshooting section of the diagnostics manual. I'll be getting to grips with that over the next few days as there are clearly many missing parts to my understanding of the circuitry used in this analyzer. If I have any problems I'll check back with you all.
I'm not sure yet if the REF unlock message was just a result of a cold oven; will have to go back over that aspect when time permits, but thanks for pointing out the possibility!

Say, anybody know any disadvantages of using freeze spray as a duster or a duster as freeze spray?? Turn one upside-down to make it work as the other, of course.? TIA.

Jim Ford

Sent from my T-Mobile 4G LTE Device

-------- Original message --------

From: Flannel Tuba <flanneltuba@...>

Date: 3/1/22 12:12 PM (GMT-08:00)

To: [email protected]

Subject: Re: [HP-Agilent-Keysight-equipment] HP8640B RF Fails Several Seconds After Power Up

@Jim: I too am a big fan of freeze spray. It can really root out faults that would otherwise be very difficult to diagnose with bench equipment, especially intermittent issues like this. I gave each of the regulator sections a nice dose of freeze spray, without any revealing results, except for the one drawback of such techniques, namely the condensation that can result after cooling the boards, which in this case would throw the regulators off until they'd dried off. Ordinarily, I avoid freezing entire sections of a circuit at once, preferring to freeze each component separately with a nice steady and directed drip from the freeze can. This not only helps eliminate the condensation issue, but saves on the freeze spray, which is not inconsequentially pricy. Unfortunately, without any extender cards, it's nearly impossible to just freeze a specific component at a time, so, firehose freeze spray it is! Anyway, it didn't expose any temperature sensitive issues on the regulator cards.

@George: I definitely plan to re-flow all of the TO3 connections, and clean the sockets and pins. Even if it doesn't fix this issue, it's good hardware hygiene in any case. I'll put all of the power transistors on a curve tracer too, and run them through a wide temperature sweep. None of them generated any notable heat while in circuit, but a flakey P/N junction can decide to fail at relative room temperatures. I will say, the day this failed, the temperature in my shop (uninsulated barn actually) was probably in the mid 40°s, F. Admittedly a silly temperature to be aligning a receiver, but it was intended to be a rough alignment. I was bored, what can I say?

@Dave: As long as I've had this 8640, is has always been positioned horizontally, so I would hope this would preclude the possibility of the lubricant creeping into the electronics. I do agree that the behavior of the 44.6V supply floating high when the oscillation stops, seems like the regulator's reaction to being underloaded, perhaps when the circuits it supplies, take a nap. Thanks for the tips on where these los might reside.?

I really need to make or buy some 15 pin extender cards. Troubleshooting such circuits without, is like trying to fish coins out of a storm drain. Anyone know a good source of such, that aren't priced by concert scalpers?

Say, anybody know any disadvantages of using freeze spray as a duster or a duster as freeze spray?? Turn one upside-down to make it work as the other, of course.? TIA.

Jim Ford

Sent from my T-Mobile 4G LTE Device

-------- Original message --------

From: Flannel Tuba <flanneltuba@...>

Date: 3/1/22 12:12 PM (GMT-08:00)

To: [email protected]

Subject: Re: [HP-Agilent-Keysight-equipment] HP8640B RF Fails Several Seconds After Power Up

@Jim: I too am a big fan of freeze spray. It can really root out faults that would otherwise be very difficult to diagnose with bench equipment, especially intermittent issues like this. I gave each of the regulator sections a nice dose of freeze spray, without any revealing results, except for the one drawback of such techniques, namely the condensation that can result after cooling the boards, which in this case would throw the regulators off until they'd dried off. Ordinarily, I avoid freezing entire sections of a circuit at once, preferring to freeze each component separately with a nice steady and directed drip from the freeze can. This not only helps eliminate the condensation issue, but saves on the freeze spray, which is not inconsequentially pricy. Unfortunately, without any extender cards, it's nearly impossible to just freeze a specific component at a time, so, firehose freeze spray it is! Anyway, it didn't expose any temperature sensitive issues on the regulator cards.

@George: I definitely plan to re-flow all of the TO3 connections, and clean the sockets and pins. Even if it doesn't fix this issue, it's good hardware hygiene in any case. I'll put all of the power transistors on a curve tracer too, and run them through a wide temperature sweep. None of them generated any notable heat while in circuit, but a flakey P/N junction can decide to fail at relative room temperatures. I will say, the day this failed, the temperature in my shop (uninsulated barn actually) was probably in the mid 40°s, F. Admittedly a silly temperature to be aligning a receiver, but it was intended to be a rough alignment. I was bored, what can I say?

@Dave: As long as I've had this 8640, is has always been positioned horizontally, so I would hope this would preclude the possibility of the lubricant creeping into the electronics. I do agree that the behavior of the 44.6V supply floating high when the oscillation stops, seems like the regulator's reaction to being underloaded, perhaps when the circuits it supplies, take a nap. Thanks for the tips on where these los might reside.?

I really need to make or buy some 15 pin extender cards. Troubleshooting such circuits without, is like trying to fish coins out of a storm drain. Anyone know a good source of such, that aren't priced by concert scalpers?

@Jim: I too am a big fan of freeze spray. It can really root out faults that would otherwise be very difficult to diagnose with bench equipment, especially intermittent issues like this. I gave each of the regulator sections a nice dose of freeze spray, without any revealing results, except for the one drawback of such techniques, namely the condensation that can result after cooling the boards, which in this case would throw the regulators off until they'd dried off. Ordinarily, I avoid freezing entire sections of a circuit at once, preferring to freeze each component separately with a nice steady and directed drip from the freeze can. This not only helps eliminate the condensation issue, but saves on the freeze spray, which is not inconsequentially pricy. Unfortunately, without any extender cards, it's nearly impossible to just freeze a specific component at a time, so, firehose freeze spray it is! Anyway, it didn't expose any temperature sensitive issues on the regulator cards.

@George: I definitely plan to re-flow all of the TO3 connections, and clean the sockets and pins. Even if it doesn't fix this issue, it's good hardware hygiene in any case. I'll put all of the power transistors on a curve tracer too, and run them through a wide temperature sweep. None of them generated any notable heat while in circuit, but a flakey P/N junction can decide to fail at relative room temperatures. I will say, the day this failed, the temperature in my shop (uninsulated barn actually) was probably in the mid 40°s, F. Admittedly a silly temperature to be aligning a receiver, but it was intended to be a rough alignment. I was bored, what can I say?

@Dave: As long as I've had this 8640, is has always been positioned horizontally, so I would hope this would preclude the possibility of the lubricant creeping into the electronics. I do agree that the behavior of the 44.6V supply floating high when the oscillation stops, seems like the regulator's reaction to being underloaded, perhaps when the circuits it supplies, take a nap. Thanks for the tips on where these los might reside.?

I really need to make or buy some 15 pin extender cards. Troubleshooting such circuits without, is like trying to fish coins out of a storm drain. Anyone know a good source of such, that aren't priced by concert scalpers?