Some questions about the HP 1670G logic analyzer

[jgalak]

I just picked up a 1670G on ebay, and have a few questions:

1) when I first powered it up, it passed all the tests.  And then, while still booting, like a dumbass, I noticed there was a floppy in the drive and ejected it.  After that, the floppy drive self-test has been failing.  Any way of knowing if I just borked the floppy, or the drive unit itself died at that exact point?  I can't find any spare floppies to test with right now...

2) and speaking of which, is it possible to replace the floppy drive itself with a USB adaptor?  I've seen that done with vintage computers, but not sure if the analyzer would work with it.

3) the next obvious point of concern is the HDD.  It's currently working, but with a drive that age it's a concern.  Is it a standard IDE HDD?  Can it be replaced with anything more modern (SSD, CF card, SD card, etc.)?  I saw some discussion about another vintage HP analyzer that suggested that only very specific CF cards worked in it, and these days even those CF cards are unobtanium.  Is the 1670G similarly picky?

4) the analyzer came with the pod cables, but not with flying leads.   Are E5383A leads correct for this?  And are there any differences between the E5383A and the (currently in production) E5383B?

5) EDIT: I thought it was just missing the knob, but it actually looks like the D-shaft the knob was riding on has been sheared off.  So I probably need to replace whatever the component is.  Service manual just lists the whole keyboard board as a single unit, there's no schematic.  Does anyone know what the part is?  Potentiometer, rotary encoder, what kind?  Can the analyzer be used without the knob, or are there some functions that can only be done with it?

Anything else I need to be aware of with this device that isn't covered by the manual?  Bear in mind that I've never used a real LA before (closest I've gotten is an Analog Discovery 2), so things that might seem obvious to you may not be obvious to me

My use case for this is to work on retro computer systems, especially s-100 systems, which is why I wanted a lot of channels.  This is strictly hobby use, in case that matters.

[petemate]

Welcome to the wonderfully frustrating world of HP logic analyzers. I have a 16700A myself and I have spent hours chasing down the various differences between cards, pods, probes, leads, etc.

I can't answer all of your questions, so I'll go with the ones I know:

3) the next obvious point of concern is the HDD.  It's currently working, but with a drive that age it's a concern.  Is it a standard IDE HDD?  Can it be replaced with anything more modern (SSD, CF card, SD card, etc.)?  I saw some discussion about another vintage HP analyzer that suggested that only very specific CF cards worked in it, and these days even those CF cards are unobtanium.  Is the 1670G similarly picky?

According to the service manual(https://bitsavers.org/test_equipment/hp/166x_167x/01670-97023_1670G_Service_Guide_200311.pdf) page 196, the HDD is an IDE harddisk. You can get some cheap IDE-to-SD card adapters(talking 30 USD or so), so I'd get one of those and try it out. You probably also need an old-time IDE compatible harddisk reader(USB-to-IDE) if you want to clone the drive instead of re-installing.

4) the analyzer came with the pod cables, but not with flying leads.   Are E5383A leads correct for this?  And are there any differences between the E5383A and the (currently in production) E5383B?

The cables for HP logic analyzer stuff are a nightmare. There are 9 different types of cables, depending on which unit and/or module you have. Luckily, Keysight has a PDF that summarizes it all: https://www.keysight.com/dk/en/assets/7018-06707/data-sheets/5968-4632.pdf Table 6 is your friend.

Basically, there are 40-pin cables and 90-pin cables. That refer to the number of pins that goes into whatever flying lead or hi-density adapter that you end up using. You have 40-pin cables. What they don't mention is that the other end of the cable(the one going into your logic analyzer) may have 50 pins or 60 pins. So you need to be very specific here regarding what cables you end up buying, cause they might not fit your specific analyzer. Also, for some reason they cost an arm and a leg on ebay.

Anyway, your 1670 series unit uses the 16710-61603 cables, which are 40 pin on the flying-lead end. The PDF tells you to use E5383A, but doesn't mention E5383B at all. I seem to recall something about E5383B has an extra 5V or clock signal on that pin 3, whereas the E5383A just says "do not connect", but I can't find it in any documentation.


One final note, instead of using the flying leads, you might want to design some sort of PCB-based adapter for the unit you work on, to ease connecting, since the flying leads are a nightmare to debug. This way you don't need flying leads and you can plug in your pod cables directly to your adaptor,  but you will need to add the "tip isolation network", which is what is inside the flying leads, to your adapter board.

[Stray Electron]

  A few things:   Re: 1   Without a floppy disk installed you should get a warning message but not a message that the drive has "failed". What exactly is the message saying? And why can't you reinsert the disk that came with it?

  Re: 4   It's a very BAD idea to buy a LA that doesn't include all of the necessary cables, leads etc!  The leads, etc are worth far more than the analyzers themselves and are usually hard to find. 

   Re: 5  How was the condition described on Ebay?  If it was "working" then it should have been complete without a broken or missing parts so you might want to file a claim with Ebay.   I've never opened up that model LA so I don't know what they use inside but my guess is a rotary encoder but being an HP product their is a very good chance that it's a custom made part. And even if it's not then the part might still be out of production. 

   I think that you need to open it up and get the part number for the disk drive and for the encoder(?) and post those before anyone can give you accurate advice about replacing either of those.

  There are a lot of third party websites that talk about the 1670 and other similar HP LAs and that have manuals and repair advice for them. Have you done a search yet?   I don't think that there is a component level service manual for them.  Most of the SMs for HP equipment of that vintage cover only circuit board replacement. I've had a lot the different HP LAs beginning with the 1600/1607 and 1630s and newer but I don't think that I've seen a CL  SM for any of them.  But there are people who have figured out a some of the details of the internals and posted them online.

  One website for the 1670D  https://blog.mateijordache.info/2022/05/31/hp-1670d-notes/

[Stray Electron]

  I saw some discussion about another vintage HP analyzer that suggested that only very specific CF cards worked in it, and these days even those CF cards are unobtanium.

  Seriously?  I have stacks of them for use in my older model DLSRs and I suspect that a lot of other people do as well.

     A quick Ebay search shows that there are "5,400+" listings for "Compact flash card".   Just be happy that you don't need a not-over 2Mb battery operated SRAM card like those required for the LeCroy scopes!

[aeg]

2) and speaking of which, is it possible to replace the floppy drive itself with a USB adaptor?  I've seen that done with vintage computers, but not sure if the analyzer would work with it.

That's probably not worthwhile. The 1670G has Ethernet, the only thing you need the floppy drive for is loading the system software after hard drive replacement.

3) the next obvious point of concern is the HDD.  It's currently working, but with a drive that age it's a concern.  Is it a standard IDE HDD?  Can it be replaced with anything more modern (SSD, CF card, SD card, etc.)?  I saw some discussion about another vintage HP analyzer that suggested that only very specific CF cards worked in it, and these days even those CF cards are unobtanium.  Is the 1670G similarly picky?

The 1670G is a portable version of the 16500 mainframe analyzer, so the information here should apply: https://www.ko4bb.com/doku2015/doku.php?id=test_equipment:hard_drive_conversion_to_cf_for_hp16500

It's no problem to get a suitable CF card, as long as you're careful to get a known compatible one.

4) the analyzer came with the pod cables, but not with flying leads.   Are E5383A leads correct for this?  And are there any differences between the E5383A and the (currently in production) E5383B?

You might have more luck searching for part number 01650-61608. I guess E5383A is the new name for the same part. Searching for HP pod may also be fruitful. You are correct in your use of the terms "pod" and "flying lead", but often the flying lead sets get listed on eBay as pods because they have stickers that say "pod 1", "pod 2" etc. Look for the rainbow colored label with the 16 channel numbers.

My use case for this is to work on retro computer systems, especially s-100 systems, which is why I wanted a lot of channels.

I think you made a good choice.

[jgalak]

  Seriously?  I have stacks of them for use in my older model DLSRs and I suspect that a lot of other people do as well.

     A quick Ebay search shows that there are "5,400+" listings for "Compact flash card".   Just be happy that you don't need a not-over 2Mb battery operated SRAM card like those required for the LeCroy scopes!

The unobtanium was the specific CF card reported to work with that LA, not CF cards in general.  There was an explanation about some signal that old HDs sent to the host, but only some CFs did, and that LA required the signal to recognize it as valid.

[jgalak]

  A few things:   Re: 1   Without a floppy disk installed you should get a warning message but not a message that the drive has "failed". What exactly is the message saying? And why can't you reinsert the disk that came with it?

I did re-insert it.  It's still showing the failure.  See photos

[Stray Electron]

   Well I have had problems with some of the old HP disk drives where the grease on the mechanism that lifts the disk dried out and caused the mechanism not to lift the disk up high enough to fully clear the read write heads. Then if you took the disk out of the drive it would catch on one head and either rip it off of it's support arm or bend the gimbal and cause the head to become misaligned.  But I thought that HP had fixed that problem but perhaps not.  Open the shutter on the disk and rotate the actual disk and look and see if you see any physical damage to the magnetic media inside. Check both sides.  If you see any then that disk is ruined. Don't use it again for anything other than a paper weight.  I ruined one of my HP BASIC installation disks by not checking the drive first.

  And you NEED to open up your machine and remove the drive and check it.  You can use any 3 1/2" FD for that, just make sure that the mechanism lifts the disk up all of the way up before you try to insert it into or pull it out of the drive. I found that a lot of the old DDs had grease that had dried out completely and had gummed up the drive. I couldn't replace the drives so I eventually had to use Brake Cleaner to get the dried up grease off.  Then regreased the DDs with a good quality gun grease that wouldn't (or shouldn't!) dry up.

  But if your drive is damaged then it's beyond any practical repair.

   My advice to anyone that buys any old HP TE that has a FD in it* is to take the drive out and check if before inserting or removing a disk. 

   * Especially if the drive hasn't been used in a long time.  I destroyed two or three FDs in some HP TE that came from Aberdeen PG and that had been sitting for YEARS in a warehouse before I got it until I finally figured out what had happened. 

   I don't know if this your problem but it's possible. 

[Stray Electron]

  Seriously?  I have stacks of them for use in my older model DLSRs and I suspect that a lot of other people do as well.

     A quick Ebay search shows that there are "5,400+" listings for "Compact flash card".   Just be happy that you don't need a not-over 2Mb battery operated SRAM card like those required for the LeCroy scopes!

The unobtanium was the specific CF card reported to work with that LA, not CF cards in general.  There was an explanation about some signal that old HDs sent to the host, but only some CFs did, and that LA required the signal to recognize it as valid.

   That's interesting.  I have a bunch of CF cards that I couldn't format in my Olympus DLSR but they would format in my friend's Nikon DLSR.  The strange thing was that they worked fine in my DLSR after they were formatted in the other camera. I think that the cards that I had trouble with were all Transcend "Industrial Grade" cards that had come out of fully functioning computers.  All of the other brands formatted and worked fine in my camera. 

[jgalak]

The unobtanium was the specific CF card reported to work with that LA, not CF cards in general.  There was an explanation about some signal that old HDs sent to the host, but only some CFs did, and that LA required the signal to recognize it as valid.

   That's interesting.  I have a bunch of CF cards that I couldn't format in my Olympus DLSR but they would format in my friend's Nikon DLSR.  The strange thing was that they worked fine in my DLSR after they were formatted in the other camera. I think that the cards that I had trouble with were all Transcend "Industrial Grade" cards that had come out of fully functioning computers.  All of the other brands formatted and worked fine in my camera.

I'd be surprised if it was the same issue with a device meant to take CF cards.  The problem was very much on the IDE side of things. 

I finally found the thread I had read, and it was, of course, on this forum

Details are here: https://www.eevblog.com/forum/testgear/solving-the-hp16500-compact-flash-card-mystery/msg0/

[av500]

Hi,

author of the post here: https://www.eevblog.com/forum/testgear/solving-the-hp16500-compact-flash-card-mystery/msg0/

I actually used an 1760G to sniff the 16500C IDE bus when trying to solve the boot mystery

In my 1760G the first thing I did was to replace the (failed) IDE drive with a CF card (the Innodisk 1GB).

I found that the 1670G firmware does not care for that value from the IDE IDENTIFY command that trips up the 16500 series.  So almost any CF card should work, IIRC my unit worked with all the cards that I tested the 16500 with...

[av500]

fun fact, my 1670G once belonged to a hard drive manufacturer as it had printed notes and instructions and a 40 IDE "through" adapter already hooked up to pod cables when it came from the eBay seller
sadly the drive was dead so I did not get the software setup they had presumably written for it.

but I had minimal effort to hook up the 16500 drive/CF card

[jgalak]

Hi,

author of the post here: https://www.eevblog.com/forum/testgear/solving-the-hp16500-compact-flash-card-mystery/msg0/

I actually used an 1760G to sniff the 16500C IDE bus when trying to solve the boot mystery

In my 1760G the first thing I did was to replace the (failed) IDE drive with a CF card (the Innodisk 1GB).

I found that the 1670G firmware does not care for that value from the IDE IDENTIFY command that trips up the 16500 series.  So almost any CF card should work, IIRC my unit worked with all the cards that I tested the 16500 with...

Oh, that's fantastic news!  Thanks!

[av500]

there might still be the 2GB limit though, I only got the 4GB card later and did not open up the 1670G again...

[av500]

there is now a patched BIOS ROM for the HP16500C that makes a lot more CF (and SD) cards work: https://www.eevblog.com/forum/testgear/solving-the-hp16500-compact-flash-card-mystery/msg6099111/#msg6099111

I can do HP16500B as well, but I cannot test it...

[Astralix]

I come back to you for the 16500B in a few weeks, I can test that when the lab is re-built and up and running.

[jgalak]

After taking the analyzer apart and putting it back together (for reasons unrelated to the FDD), the floppy disk controller is now passing the self-test.  Probably a loose connection that got inadvertently restored.

[hp3310a]

Contemplating a 1673G as my first LA, having read all I could find about the IDE - to - CF card conversion I'm utterly confused. The official service guide for the 167xG says it's a 40 PIN 3.5" IDE disk. However, @BloodyCactus posted a picture some time ago of the disk which is a 44 PIN 2.5" IDE. Which is it, did they change? What is the right CF adapter? Some adapters have no bridging components and some have a bunch components. Thanks for pointers!

[gslick]

Contemplating a 1673G as my first LA, having read all I could find about the IDE - to - CF card conversion I'm utterly confused. The official service guide for the 167xG says it's a 40 PIN 3.5" IDE disk. However, @BloodyCactus posted a picture some time ago of the disk which is a 44 PIN 2.5" IDE. Which is it, did they change? What is the right CF adapter? Some adapters have no bridging components and some have a bunch components. Thanks for pointers!

1673G is the lowest member of the 1670G series with 34 total channels and 2 state clocks. A 1672G with 68 total channels and 4 state clocks would be a nice upgrade if you can find one of those for a reasonable deal instead of a 1673G (or even better, a 1671G or 1670G). But in any case, if you want a portable old school HP / Agilent logic analyzer, the 1670G series is the nicest of the portable old school HP / Agilent logic analyzers.

I'm pretty sure all of the 1670E and 1670G series use 44-pin 2.5" IDE drives, not 40-pin 3.5" IDE drives that the older series use. And I'm pretty sure that I replaced a failed or missing 44-pin 2.5" drive in one of mine with a Syba SD-ADA45006 Dual Compact Flash to 44 Pin IDE 2.5" Adapter Enclosure, and an InnoDisk 2GB iCF4000 CF card. One nice thing about that particular adapter is that it has mounting holes which line up exactly with standard 2.5" drive mounting holes so it was a drop in replacement.

I'd verify that I did go with that exact setup and take some photos, but I have the small problem of currently having (4) 1670G series and (1) 1670E series without notes on which one I might have done the drive swap, and it would take some time to pull the covers of them to find the one with the drive swap.

[hp3310a]

Contemplating a 1673G as my first LA, having read all I could find about the IDE - to - CF card conversion I'm utterly confused. The official service guide for the 167xG says it's a 40 PIN 3.5" IDE disk. However, @BloodyCactus posted a picture some time ago of the disk which is a 44 PIN 2.5" IDE. Which is it, did they change? What is the right CF adapter? Some adapters have no bridging components and some have a bunch components. Thanks for pointers!

1673G is the lowest member of the 1670G series with 34 total channels and 2 state clocks. A 1672G with 68 total channels and 4 state clocks would be a nice upgrade if you can find one of those for a reasonable deal instead of a 1673G (or even better, a 1671G or 1670G). But in any case, if you want a portable old school HP / Agilent logic analyzer, the 1670G series is the nicest of the portable old school HP / Agilent logic analyzers.

OK, thanks, I'll keep my eyes open. The prices you mention (in various posts on the forum) don't seem to be doable anymore. I guess everyone my age rekindled their love for 20-30 year-old equipment just before I did.

I'm pretty sure all of the 1670E and 1670G series use 44-pin 2.5" IDE drives, not 40-pin 3.5" IDE drives that the older series use. And I'm pretty sure that I replaced a failed or missing 44-pin 2.5" drive in one of mine with a Syba SD-ADA45006 Dual Compact Flash to 44 Pin IDE 2.5" Adapter Enclosure, and an InnoDisk 2GB iCF4000 CF card. One nice thing about that particular adapter is that it has mounting holes which line up exactly with standard 2.5" drive mounting holes so it was a drop in replacement.

OK, thanks. The Syba isn't available in Europe apparently but I found a number of different adapters on Aliexpress.

This one has a bunch of components, so doesn't seem passive: https://www.aliexpress.com/item/1005010803189954.html

Another one I found comes without any components basically just a PCB with two connectors: https://www.aliexpress.com/item/1005010592155522.html

I don't understand how those two can do the same thing.

I'd verify that I did go with that exact setup and take some photos, but I have the small problem of currently having (4) 1670G series and (1) 1670E series without notes on which one I might have done the drive swap, and it would take some time to pull the covers of them to find the one with the drive swap.

No need, I'll just wait until I have it and take a look. Thanks of the offer!

[gslick]

OK, thanks, I'll keep my eyes open. The prices you mention (in various posts on the forum) don't seem to be doable anymore. I guess everyone my age rekindled their love for 20-30 year-old equipment just before I did.

Outside of the US, these have probably always been expensive to acquire. In the US, reasonable deals can still be found.

For example, this 1672G just sold on Jan 17, 2026 for $50 (plus it would have cost an additional $110 or so shipping to my location, plus sales tax):

https://www.ebay.com/itm/177755047430

It was listed as "For parts or not working", but the self tests were shown as all passing except for the ROM test, which I believe could be corrected by reloading the flash from disk. If I didn't already have a few 1670G series analyzers I probably would have been tempted to bid on it. There was only a single bid.

[av500]

This one has a bunch of components, so doesn't seem passive: https://www.aliexpress.com/item/1005010803189954.html

Another one I found comes without any components basically just a PCB with two connectors: https://www.aliexpress.com/item/1005010592155522.html

I don't understand how those two can do the same thing.

get the one with no components, a CF card is basically the same as a 5V HDD, I have the same simple one in my 1672E. And all the mystery about "magic" adapters or CF cards has been solved and mostly concerns the 16500 series