You might check the catalog at probemaster.com

These are not Agilent/HP probes, but their own OEM designs, but there's some chance that they will have accessories which will fit your probes.? I found, a few years ago, that their screw-in probe tips are a good fit for the probes on the venerable HP 8405A vector voltmeter (and are much less expensive than new-old-stock HP).

This is most probably an 8566 adjustment problem. Look over the adjustment procedure and you will find a section where the attenuators are adjusted. I'll try to find time to look up the exact section, but I remember doing this and correcting similar errors.


Quoting DW <wilson2115@...>:

Here is a thought, if someone with a 8566 could reproduce my results by injecting a -20dBm 10 Mhz signal and setting the reference level to -20dB and set the scale to 1dB. Then with the signal generator start dropping the signal from -20dBm to -30dBm in 1dB increments. Does the trace start to fall off towards the bottom of the screen compared to 2dB and 5dB?

开云体育

Hello,?

as i saw, i nether see anyfing on the screen os the HP 182T.

Except!!!? Look at the vidéo...very strange

All is good connected.? The input N go to the block attenuator

some idéas??

cdt

it's better with the files

hello,

i have repard the displays
This analyzer never allowed me to display anything except once , with a generator and a 5v signal which is a bit strong

May you tell me if the?if the BNC connector has been replaced by an N. the plug information is not clearly visible? ---> see picture
May you tell me if the frequency scanning operation seems normal to you (I have repaired the displays)? --->see the vidéo

Thank's for your returns

cdt

The following files have been uploaded to the Files area of the [email protected] group.

• /Catalog's/HP_140A_brochure.pdf
• /Catalog's/HP_180A_Brocchure.pdf

By: Ken Eckert <eckertkp@...>

---

The following files have been uploaded to the Files area of the [email protected] group.

• /8000 to 9999/8640 B Signal Generator Op & Cal also Repair History Information/HP_8640_series_Service_Training_manual.pdf

By: Ken Eckert <eckertkp@...>

Anyone have any good reasonably priced sources for scope probe parts?
Looking for hook tip for Agilent HP 1160 mini probe among other things.
The recent ebay listings seem to be missing the hook tip in the accessories cases.

Wally KC9INK

Hi Alberto,

no worries, one purpose of this forum is to contribute and share experience when someone is in trouble with a HPAK instrument, so just stay on.

I assume that you have checked that, on A34, the existence of the 100kHz clock signals around U9, 10, 14 and the signal at TP3, correct? Something happening at U15C, U3B? But not signs of life at TP2?
BTW, it is very helpful to go through the functional descriptions in Vol.I Section VI to understand what is happening inside the 3585A. If completed, check the following:
- fault isolation procedure in Vol.II from pg. 8-1 (hint about which loop is not locked on pg. 8-7)
- the LEDs indicate which loop might be affected, see Vol.II table 8-4 (pg. 8-10)
That should give you an indication about if the problem really is located on A34.

Chris

The 576 manual is the August 1984 revision and in excellent condition.

The "Type 172 Programmable Test Fixture" for the 576 is in likewise excellent shape.

I want to sell them as a pair, they'll be shipped from Calgary, AB, Canada and UPS Ground into the ConUS I guess might run $US50-75.00, depending.

The 172 comes with a programming card and I swear up and down I have a slew of original pins and an extra couple of programming cards sitting in one those places where I'll be -sure- to be able to locate them. They're included once I do.

A cleaned up, OCR-d copy of the manual from the TekWiki is here:




PayPal pretty much works but for unknown "reasons" that I ascribe to brain dead AI it has begun randomly withholding payments into and transfers out of the account, so I'll ask that any payment be sent as, "Money to those you trust" or whatever they call it these days.

Hit me off list please at sales – at – pearl-hifi – dot – com

Liam

Hi Chris,

I just checked before the A21 unit, without pulling out it, according to the Service Group B of Section 11: when I started directly from the "Service" chapter, the "LOCAL OSC. UNLOCKED" error led me to that Group. By following the "Main Local Oscillator Troubleshooting Tree" (11-151/11-152), I found perfectly within the tolerances the following signals:

• 90 MHz ± 10 Hz at A21J2
• 10 MHz?± 2 Hz at A21J6
• 100 kHz?± 2 Hz at A21J9
• ≥ 1 V pulses at A21J8

and so on in the flowchart, choosing YES until the last decision block, where is asked if any LED of the A34 board is blinking: before the replacement of the 2N3055 in that board, the answer was NO, but now I don't know if the slow blinking of the FRN LED can be interpreted as "blinking" and I have to change the direction... The REF LED is off at power on, but becomes on after warmup: at that moment, the sounder, that follows the FRN LED, ceases beeping.

Now, by restarting from Section 5 - as you advised - the first step I should begin from is § 5-7 "90 MHz Reference Board Adjustment (A21)": in fact I just checked the voltages of the Low Voltage Power Supply and I should prefer to avoid checking its current protection. NB In Section 11 Group B the frequency counter and the RF synthesizer had to be externally sync'd to the 10 MHz reference output of the 3585A, but in Section 5 this is true only for the synthesizer (see § 5-5). Therefore I will sync the frequency counter to my GPSDO 10 MHz reference.

Last (by now): you wrote that in you troubleshooting you bought a second unit as donor, to help you focus the possible fault in case of multiple failures. I have not this possibility, unless buying certain replacement boards: it is a little expensive approach and meanwhile I got almost all the ICs of the A34 board that I considered possibly involved, by following the schematic diagrams up to the TP2, where I cannot find the expected "pulses"... I didn't replace all of them, but now I'm dubious if a spare A34 board could be a good choice.

PS if this posting begins boring someone, please tell me: I will go on in private form.

Tnx de Alberto, IZ2EWV

Sorry, yes. 8924C

I have a question for any HP4140B users out there... Mine seems to power up with an offset of around -230fA when on the 1pA range. After about an hour's warmup this drops to around -120fA but no lower. And the 'Zero' button has no effect (presumably as it says it can only compensate for +/- 100fA?).

I have tried adjusting A1's offset as per the 'adjustments' section of the manual, but it doesn't change things. It seems to be a 'real' current - leakage possibly (the triaxial socket is clean, not looked at the A1 input board yet). Has anyone had a similar problem and if so did you manage to cure it?

After researching the matter of copying 4145A diskettes I've concluded that my
earlier statements regarding the diskette format were totally wrong.

I have now made copies, copies of copies, etc. of the original HP4145A
diskette that came with my 4145A - and it was simple and straight-forward.

I was simply WRONG about the diskette being hard sector. I was told that by
the previous owner - who is a technically astute person - and I just believed
him. I thought I had checked it myself, but that must have been an "illusion".

Today I used IMD to read my original HP diskette on my "copy stuff PC". I used
a floppy drive capable of single to quad density to create the "copy
diskettes". The parameters I used were 40 tracks, single side and double step.

My original diskette read in flawlessly and created an IMD image file. I then
used that file to create another diskette. I then read that diskette to create
a second IMD file - and used that file to produce another diskette (copy of a
copy).

I also used a 4145A IMD image I retrieved from the Internet and used it to
create a third diskette.

I tested out all of the diskettes on my HP 4145A - and ALL worked flawlessly.

In short, the diskette is NOT weirdly formatted! It is single density (FM -
250K), 9 sectors/track, 256 byte sectors for a total of 360 sectors on the
diskette.

Sorry that I didn't research this properly before I made invalid comments on
this list and wasted Dave McGuire's time (and energy) and others who were
following our discussion...

Best,
Lyle

BTW: I studied the 4145A schematics and the chip associated with the floppy
controller - which is a Fujitsu MB8866. It only is capable of handling a
single index and its single density FM format and frequency is the same as that
of an IBM 3740. It is also capable of MFM double density (not used in the HP
4145A).

=========

On Fri, 4 Jun 2021 18:39:27 -0400
"Dave McGuire" <mcguire@...> wrote:

On 6/4/21 5:24 PM, Lyle Bickley wrote:

Uhh, waitaminute. Is it possibly the case that there are two
different versions of the 4145A? Or maybe that it can boot from EITHER
hard- or soft-sectored media?? The latter would be most unusual. This
is the first I've heard of this; I had assumed (sorry!) that you were
just misremembering about your 4145A's boot disk being hard-sectored.

When I got my 4145A (and a floppy diskette that would boot) I talked with
the previous owner (a senior Google Robotics guru) and he told me the
5.25" FDD was hard sectored and would not copy on anything he had. When I
got the 4145A home, I checked the diskette - and it was easily observed to
be hard sectored.

Wow, ok.

I then went online and checked this site and Googled other specific 4145
sites and found the following, seemingly definitive, information:

...

After reading the above - and observing the hard sector diskette, I didn't
even try to copy the 4145A diskette.

That's reasonable.

I subsequently used Dunfield's "imagedisk" to make a copy of my 4145B
diskette [which I attached in an email for folks on this list].

Excellent. :-)

We should probably suss this out.

Agreed!

So yes, thank you for NOT suggesting that perhaps I don't know how to
accurately identify a hard-sectored disk. ;)

I just went and looked at it a THIRD time, because I know just how
little sleep I've been getting lately. ;) Spinning the media around
inside its jacket, there is precisely ONE hole visible through the
sensor window as the media makes a complete turn. One. And yes, it's a
5.25" disk, and the box says "4145A" on the front. It has the original
beige drive with the flip-up front door; I don't recall the manufacturer
of the drive offhand.

I wonder if I have some sort of weird variant of the 4145A? (this one
is the only one I've ever owned or directly used)

I'll have to give it a shot - I picked up the zip file 4145A image - and
have a linux/DOS (dual boot) system with both low/quad density and high
density 5.25" diskettes. (This system is only used to make copies of
"weird" FDDs).

I have one of those set up as well, with an 8" drive connected too, in
an external chassis with a switchbox and one of John Wilson's FDADAP
boards to handle the TG43 signal and such.

Yup, mine has all that, too ;)

Excellent.

That system also has a 9-track tape drive, as well as 3480 and 3490 (IBM
mainframe) cartridge tape drives, and a DEC TZ85 for reading DEC TK50 and
TK70 tapes.

I still have a DEC TK50 attached to mine -

Uh, by what interface?

but gave my HP 9-track tape drive
(800/1600/6250) to the Computer Museum of America...

Sigh...black hole...

I also use my vintage MB's integrated floppy controller - which has handled
every soft sector format I've "thrown" at it. I have HD and low density
3.5" and 5.25" and Dual 8" FDDs. So we have similar setups (especially
before I donated my tape drive). :)

Very cool.

Not familiar with "GreaseWeazle" - but it sounds similar to the KyroFlux.

Yes, a similar idea, but a newer implementation using one of the later
crop of fast microcontrollers, and its host interface is USB. All open
source, of course.

[BTW: I'm on the PDP-1 Restoration Team at the Computer History Museum
(CHM) and have on several occasions helped the Museum copy/analyze
tapes/diskettes, etc.]

Yes, I know you're on that team. My hat's off to you! :-)

-Dave

--
73 NM6Y
Bickley Consulting West


"Black holes are where God is dividing by zero"

I think that this has been asked before, however I am not aware of a definitive answer.
My question is were or how can I obtain the 1D2 option for the 35670A?
This appears to be a software upgrade (via floppy disk) but I have seen references to ROM upgrades. I am confused.

My thanks for any assistance with this.

Mark

Maybe should be making a new topic for "Reading/Writing Unusual Disks"

For those interested in Kryoflux/Greaseweasel, also have a look at

I killed my Kryoflux (dont ask...) and found FluxEngine when looking for a replacement.

I have the parts on my bench waiting so I cannot vouch for it, but it's a very economical alternative to KryoFlux.

Very nice project indeed!
Thank you for sharing