Re: Adding front panel output to 8340B
Why not install a relay and have both front and rear outputs.? I've done that and postd some pictures of how it was done in the files section.
Cheers!
bruce
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Re: Adding front panel output to 8340B
Reg,
Send me a PM, my replies to you are bouncing.
Steve
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On Nov 22, 2023, at 7:31?AM, Reginald Beardsley via groups.io <pulaskite@...> wrote:
?Steve,
Please send me the drawing. I've got machine tools. A list of relevant parts numbers would be a huge help. The manual I have is a 500+ scan of multiple manuals and it's very difficult to find the correct section. I settled on using a 1 TB iPad Pro as a documentation repository. The size is handy, but the UI is awful.
The cal sheet is there. At this point I don't know what I have. Yesterday was just a quick function test before the return period expired. As is common, it didn't work on arrival, but was fine after I seseated connectors I could access. All I've done is enough work to verify the 8340B worked.
As soon as the basic lighting and wiring is done I'm building a 12'x16' screen room using 28 gauge galvanized steel with soldered seams and full TEMPEST treatment, building a 2nd 6 bay rack and cabling it up so I can use it.
I've got workmen coming next week to wire and light my shop. I finally conceded I'm too old and out of shape to do anything but minor changes myself. Worse yet, I haven't bent conduit in over 40 tears and that's as real art.
Because of space limitations both the bench and the racks are going to be on rails. The racks for rear access and the bench to bring the bench to the correct instruments with all graphic displays at eye level. Bench at 90 degrees between the racks. Lots of metalwork to do.
Thanks,
Reg
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Re: HP 4145A - Power Transistor Measurement Setup
On 11/21/23 21:37, Wolfgang Schraml wrote: I've been playing around with my repaired HP 4145A, and the setup to measure power transistors, as described in the issue of October 1982 of the Hewlett-Packard Journal (page 10), caught my attention.
The article doesn't provide a lot of detail on how to set up the analyzer. Since I struggled with it for a while, I will describe below how I configured everything to measure a 2N3055 transistor. Someone may find the information helpful.
1) Hardware Setup
I pretty much followed the diagram in the article:
2) Configuration of the 4145A
The following screen captures show how I set up the SMUs and the calculations to convert the sweep voltage into VCE and the output current voltage of the 6024A into IC:
This is the result?(single measurement, long integration time):
?At this point, the settings can be fine-tuned to your needs. This is great information, thank you for documenting this setup! -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: Adding front panel output to 8340B
Dave,
Apart from the firmware and semirigid coax needed, the installation is straightforward. If you want the best accuracy there is a detailed attenuator calibration procedure to follow. It¡¯s a bit laborious and of course, requires more (and calibrated!) test equipment.
If you shop for an attenuator try to get one with the mounting plate and ribbon cable attached. They do go for silly money but occasionally a reasonably priced (for me, anyway) one shows up. If I remember correctly I paid about $100 shipped for my last one, with the mounting plate and cable and a 30 day return privilege.
Steve
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On Nov 22, 2023, at 3:13?AM, Dave Brown <2c39a@...> wrote:
?
Steve
Apart from the firmware update, is there much involved in doing a retro -fit of the attenuator to a 'front output' instrument that does not have it? I see the attenuator is out there- at prices that vary - from the sublime to the ridiculous.......
DaveB, NZ
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Steve - Home
Sent: Wednesday, November 22, 2023 11:40
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] Adding front panel output to 8340B
Reg,
I¡¯ve done it before. It¡¯s a task but not terribly difficult. The biggest problem is finding the bracket required to mount the connector to the front panel frame, the HP part number is 08340-20076. It¡¯s got some odd offsets machined into it so it will fit where it has to fit. There¡¯s a guy in France that has one or two listed on eBay for $120 plus $53 shipping. I think the listing says ¡°or offer¡± but I haven¡¯t contacted him. I was tempted to try to machine one with the help of a friend but that never happened. I managed to snag one with a connector on eBay for $50. Another guy doing the same change came up with an alternate method of mounting the connector but I don¡¯t know how mechanically stable it is compared to the original bracket.
You will need to modify the firmware to account for the smaller loss in the semirigid coax as the run to the rear panel is obviously longer. Will you also be adding the 08340-60175 attenuator? If so that¡¯s another firmware change. The firmware changes are done from the front panel so it¡¯s not a big deal. Hopefully your unit still has the cal constant/firmware paper listing in a bracket at the left rear inside the top of the unit.
I¡¯m getting ready to do an attenuator/rear to front output update on a unit arriving tomorrow or Friday.
Let me know if you have any questions. I have a hand-drawn sketch of the bracket, with dimensions my friend made but as I said, I found one so I never made the bracket and couldn¡¯t guarantee the drawing and dimensions are 100% correct.
Steve Krull
WB0DBS
On Nov 21, 2023, at 3:06?PM, Reginald Beardsley via groups.io<pulaskite@...> wrote:
?How gnarly is doing that? The one I just bought is rear output only.
Thanks,
Reg
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Re: Adding front panel output to 8340B
Steve,
Please send me the drawing. I've got machine tools. A list of relevant parts numbers would be a huge help. The manual I have is a 500+ scan of multiple manuals and it's very difficult to find the correct section. I settled on using a 1 TB iPad Pro as a documentation repository. The size is handy, but the UI is awful.
The cal sheet is there. At this point I don't know what I have. Yesterday was just a quick function test before the return period expired. As is common, it didn't work on arrival, but was fine after I seseated connectors I could access. All I've done is enough work to verify the 8340B worked.
As soon as the basic lighting and wiring is done I'm building a 12'x16' screen room using 28 gauge galvanized steel with soldered seams and full TEMPEST treatment, building a 2nd 6 bay rack and cabling it up so I can use it.
I've got workmen coming next week to wire and light my shop. I finally conceded I'm too old and out of shape to do anything but minor changes myself. Worse yet, I haven't bent conduit in over 40 tears and that's as real art.
Because of space limitations both the bench and the racks are going to be on rails. The racks for rear access and the bench to bring the bench to the correct instruments with all graphic displays at eye level. Bench at 90 degrees between the racks. Lots of metalwork to do.
Thanks,
Reg
|
Re: Adding front panel output to 8340B
Steve
Apart from the firmware update, is there much involved in doing a retro -fit of the attenuator to a 'front output' instrument that does not have it? I see the attenuator is out there- at prices that vary - from the sublime to the ridiculous.......
DaveB, NZ
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Steve - Home Sent: Wednesday, November 22, 2023 11:40 To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] Adding front panel output to 8340B Reg, I¡¯ve done it before. It¡¯s a task but not terribly difficult. The biggest problem is finding the bracket required to mount the connector to the front panel frame, the HP part number is 08340-20076. It¡¯s got some odd offsets machined into it so it will fit where it has to fit. There¡¯s a guy in France that has one or two listed on eBay for $120 plus $53 shipping. I think the listing says ¡°or offer¡± but I haven¡¯t contacted him. I was tempted to try to machine one with the help of a friend but that never happened. I managed to snag one with a connector on eBay for $50. Another guy doing the same change came up with an alternate method of mounting the connector but I don¡¯t know how mechanically stable it is compared to the original bracket. You will need to modify the firmware to account for the smaller loss in the semirigid coax as the run to the rear panel is obviously longer. Will you also be adding the 08340-60175 attenuator? If so that¡¯s another firmware change. The firmware changes are done from the front panel so it¡¯s not a big deal. Hopefully your unit still has the cal constant/firmware paper listing in a bracket at the left rear inside the top of the unit. I¡¯m getting ready to do an attenuator/rear to front output update on a unit arriving tomorrow or Friday. Let me know if you have any questions. I have a hand-drawn sketch of the bracket, with dimensions my friend made but as I said, I found one so I never made the bracket and couldn¡¯t guarantee the drawing and dimensions are 100% correct. Steve Krull WB0DBS On Nov 21, 2023, at 3:06?PM, Reginald Beardsley via groups.io<pulaskite@...> wrote:
?How gnarly is doing that? The one I just bought is rear output only.
Thanks,
Reg
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Re: Adding EFC to an 8662A
Alan,
I equipped my HP8662 with an EFC-Input for phase-noise measurements
with a HP11848 Phase Noise Interface. On the attached image with an extract
of plate 18 of the service manual you can see my modification (blue).
The green curve in the small graph shows the resulting frequency deviation with
a variation of the input tuning voltage over a range of +10.0 ... -10.0 Volts.
One can see that the resulting frequency deviation covers a range of
approximately 25.0E-08
The purple curve is a comparison with a HP8644B which is by default equipped
with an EFC-Input.
I hope that this helps.
Kurt
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Slightly off topic: looking for Fluke 8860A ROM image
Hi,
Sorry for the off topic, but maybe someone can help me. I am looking for the ROM image of the outguard controller (A3 board, U9 ic). If anyone has it, or can make a dump, that would be of a great help. I've been looking for it at the usual places (KO4BB, eevblog, xdevs, fluke mailing list and facebook group, etc.) , but was not able to find it. Looks like bit-rot in this rom is quite common, as several people were looking for the image but apparently no one has made one yet.The rom is socketed and easily accessible, so it should be fairly simple to dump it. Bit of a pin swapping is required as it is not 2732, but 2532 eprom pinout.
Thank you in advance.
Szabolcs
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Re: How do I update HP 3488A manuals in the Wiki?
I found a better copy online. The other thing is one of the manuals in our Wiki is for the 3499, so is misfiled.
Steve
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HP 4145A - Power Transistor Measurement Setup
I've been playing around with my repaired HP 4145A, and the setup to measure power transistors, as described in the issue of October 1982 of the Hewlett-Packard Journal (page 10), caught my attention.
?
The article doesn't provide a lot of detail on how to set up the analyzer. Since I struggled with it for a while, I will describe below how I configured everything to measure a 2N3055 transistor. Someone may find the information helpful.
?
?
1) Hardware Setup
?
I pretty much followed the diagram in the article:
?
?
2) Configuration of the 4145A
?
The following screen captures show how I set up the SMUs and the calculations to convert the sweep voltage into VCE and the output current voltage of the 6024A into IC:
?
?
?
?
?
?
This is the result?(single measurement, long integration time):
?
?
?At this point, the settings can be fine-tuned to your needs.
?
?
Regards,
Wolfgang Schraml
KI7PFX
?
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Re: HP 8350B sweeper behavior
I think this might be the datasheet for the wet slug tantalum cap.
https://www.vishay.com/docs/40023/109d.pdf
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Bunch of old HP gear in Tucson, AZ USA
For anybody who is interested in old HP test equipment and is in driving distance of Tucson, AZ, Elliott Electronic Surplus just got a bunch of the old vintage stuff. Among the newer, was a 141. There are a number of signal generators, a VTVM a Couple of frequency counters, an HP3450 and others. I didn't examine it too much, as I prefer the newer stuff, but it appeared to be in decent shape, not having been out in the weather and such.
BobH
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Re: Adding front panel output to 8340B
Reg,
I¡¯ve done it before. It¡¯s a task but not terribly difficult. The biggest problem is finding the bracket required to mount the connector to the front panel frame, the HP part number is 08340-20076. It¡¯s got some odd offsets machined into it so it will fit where it has to fit. There¡¯s a guy in France that has one or two listed on eBay for $120 plus $53 shipping. I think the listing says ¡°or offer¡± but I haven¡¯t contacted him. I was tempted to try to machine one with the help of a friend but that never happened. I managed to snag one with a connector on eBay for $50. Another guy doing the same change came up with an alternate method of mounting the connector but I don¡¯t know how mechanically stable it is compared to the original bracket.
You will need to modify the firmware to account for the smaller loss in the semirigid coax as the run to the rear panel is obviously longer. Will you also be adding the 08340-60175 attenuator? If so that¡¯s another firmware change. The firmware changes are done from the front panel so it¡¯s not a big deal. Hopefully your unit still has the cal constant/firmware paper listing in a bracket at the left rear inside the top of the unit.
I¡¯m getting ready to do an attenuator/rear to front output update on a unit arriving tomorrow or Friday.
Let me know if you have any questions. I have a hand-drawn sketch of the bracket, with dimensions my friend made but as I said, I found one so I never made the bracket and couldn¡¯t guarantee the drawing and dimensions are 100% correct.
Steve Krull
WB0DBS
toggle quoted message
Show quoted text
On Nov 21, 2023, at 3:06?PM, Reginald Beardsley via groups.io<pulaskite@...> wrote:
?How gnarly is doing that? The one I just bought is rear output only.
Thanks,
Reg
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Re: HP 16500C looking for logic analyser boards that are functional
Hi Damien,
On your photo, the four larger pads where you've placed a red dot are NOT vias.? They are examples of test points that bring signals to the bottom of the board.? They don't go anywhere else and are provided for probably automated testing, or possibly troubleshooting for HP technical folks.? There are a few pads of this larger size that also have a hole in the center of them in some of your other photos, and those ARE vias combined with a test point.
The three smaller pads you show with red dots are vias and they connect other layers not visible together (thru vias)? The green coating, like a transparent paint, is soldermask.? If the soldermask is intact with no white or green fuzz surrounding it or inside it, the via is probably ok (although not guaranteed).? If it helps, the green fuzz is corroded copper, and the white fuzz is corroded solder.
I'm not sure what the soldersucker is going to do for you in that photo.? You won't find find solder in those via holes.? And the larger test pads in the photo that have solder on them are not part of an operational signal path.
Instead of going after the vias first, I would recommend prioritizing your efforts to find and fix bottom layer tracks that have been severed, including on the component connections such as the resistor packs, and when they pass through a test pad.? I've fixed somewhere around 20 of these series modules by only repairing severed tracks.
I also have a similar number of dead boards, almost all with severe corrosion on multiple thru vias, and some of them so severe that the annular copper ring is completely gone.? Although it's not impossible to fix destroyed vias, at some point you should evaluate if a replacement card for $50 is worth your time so you can get on with your actual application for the 16500C.
So again, I would recommend end-to-end testing of all signal tracks from via to via as a first step before even warming up any soldering equipment.? And start with those in areas where corrosion is showing, and when the tracks cross under or near the former plastic runners.? Don't trust a visual inspection.
When you find a bad track, try to locate the bad section by by moving your probes closer and closer on the track.? You need very sharp probes to get through the soldermask.? When you've zeroed in on the bad section, mark it and move on to the next track.? (I use small red arrow stickers, Brady DIA-250-RD.)? Keep in mind there are sometimes multiple breaks in a track.? After you're done testing, go back and fix everything you found.
Since your boards were working at some point, you might only find one or two problems.
Also, did these two boards die with the exact same error and at the same time?? If so, it's not an impossible coincidence, but it does raise the specter of a problem elsewhere in the system.
-mark
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Adding front panel output to 8340B
How gnarly is doing that? The one I just bought is rear output only.
Thanks,
Reg
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Re: HP 8350B sweeper behavior
Ed,
nice and important to know. I also read your mentioned older posts.
Thanks
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Re: HP 8350B sweeper behavior
Nope. The negative end looks rubbery-colored, but it's just very dark tarnish - try scraping it off to see for sure. Some types do have rubbery seals at both ends, but if so, you would see the outer crimped zones where the case is necked down to retain the guts.
Ed
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Re: HP 8568A Spectrum Analyzer failure, BOTH INSTR CHECK LEDs off, Test Pattern OK and keyboard not responding once Self-Test passed.
Hi everyone,
Problem found. In fact there was no problem i think, I found an unplugged coax cable, that goes from A27 Time Base to A16 20 Mhz reference board.?
This is where i realize, i had no chance to get it worked from the start, there's no A27 Time Base aka OCXO in my 8568.... this is why it never worked....
Now i have to find an OCXO for an 8568A, i have no part number for such thing... if someone has one for cheap, contact me.
Or i have to use an EXT REF instead, aka external OCXO.
I feel so dumb.
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Re: HP 8350B sweeper behavior
Martin,
it looks like rubber on both sides on the old cap. Is that right?
(Your msg. 140464)
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Re: HP 8350B sweeper behavior
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Dave McGuire
Steve Holland
Stefan