Hi Guys,

having repaired an 8341A myself, I know it is a very complex bit of electronics. So, repairing it without having full and accurate service manuals with readable schematics is "poking in the fog", as we would say in german.
Unfortunately, the manuals currently available on the web are either not complete, unreadable, or not for the 8341A / 8340A (the 8341A and 8340A are AFAIK the same machines, the only difference is the output connector and the frequency range; so the 8340A is actually an 8341A with selected components).
I had access to the complete service manuals in paper form (these are also very rare on the 'bay!), and I already started making scans of them last year. A friend of mine completed the scans, and I merged the PDFs (using LaTeX, it was quite a hassle but I think the result is acceptable) and OCRed them. I just uploaded the schematics to my web server. Here you go:

Volume 1:


Volume 2:


Volume 3:


Volume 4:


I would not go so far and say the PDFs are perfect, but at least they are for the 8340/1A AND readable AND complete. It should also help troubleshooting the power supply problems. In my opinion, it may be possible that it is a flaky tantaulum cap because I recently repaired a 5335A counter which didn't power on. Its power supply was shorted by a tantalum cap, and the cap didn't even get hot because its resistance was so incredibly low.
Further, it could also be a shorted feedthru capacitor on the YIG oscillator like it was the case in my repair. The YIG main coil is connected on one side to -40V as far as I remember. See Vol 3, page 210 and 220. The YO driver is A55 on page 261. The power supply starts on page 314, vol. 4.

I hope the PDFs will be helpful for others.

Best
Tobias
HB9FSX

________________________________________
From: [email protected] [[email protected]] on behalf of David Slipper [softfoot@...]
Sent: Tuesday, July 16, 2019 18:43
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 8340a Synth. Sweeper A53 -40V F2 blowout question

I have certainly had them explode when near the rated voltage - I have a
burn scar on my hand from a flying fragment.

Always wear safety glasses - at least for the first few power-ups.


On 16/07/2019 17:27, Dale H. Cook wrote:

On 7/16/2019 11:07 AM, Chuck Harris wrote:

Tantalum capacitors are among the most reliable
...
The failures tend to happen when they are operated at
a voltage too close to the rated voltage.

That has certainly been my experience.

I have certainly had them explode when near the rated voltage - I have a
burn scar on my hand from a flying fragment.

Always wear safety glasses - at least for the first few power-ups.

On 7/16/2019 11:07 AM, Chuck Harris wrote:

Tantalum capacitors are among the most reliable
...
The failures tend to happen when they are operated at
a voltage too close to the rated voltage.

That has certainly been my experience.
--
Dale H. Cook, Radio Contract Engineer, Roanoke/Lynchburg, VA

Tantalum capacitors are among the most reliable
capacitors ever made. Unlike aluminum electrolytic
capacitors, they have no inherent age related failure
mechanism... And yet, they do fail... sometimes
catastrophically.

The failures tend to happen when they are operated at
a voltage too close to the rated voltage.

How can this be? Engineers are always adding in
conservative fudge factors to make the things they
design safer and more reliable.

Back in the day when these scopes were designed,
the manufacturers were touting how the capacitors
did not need any extra design margin added to the
voltage rating. They said that it was perfectly
safe to use a 6V capacitor at 5V, and a 16V capacitor
on a 15V power supply line. They said the design
margin was already added in...

They were wrong! Well, sort of...

The result of following their advice was the device
you designed may only work for 10 years instead of
the 110 years it would if you used a more conservative
rule for specifying the capacitor's rated voltage.

A general rule that works most of the time is to leave
dry slug tantalum capacitors alone until they fail, and
then replace them with a new capacitor of 2x the circuit's
expected maximum operating voltage.

If you follow that rule, the capacitor should never fail
in hundreds of years. There are space probes navigating
the cosmos that are full of tantalum capacitors derated
by the 2.5x rule NASA requires.

Wet slug tantalum capacitors, though reliable, suffer
from a design flaw in the sealing of their cases. The
electrolyte is sulfuric acid, and the lead that leaves
the seal (positive terminal) is tantalum wire. The acid
crawls up the tantalum wire, past the teflon seal, and
on down to the pcb, where it causes corrosion damage.

They should be inspected, and if there is any little crusty
area around where the wire passes through the teflon seal,
replaced with a new wet slug tantalum. Or, if you can fit
the larger size, a film capacitor.

Generally, wet slug tantalum capacitors are too high voltage
for replacement with dry slug... and too low leakage for
replacement with aluminum electrolytic capacitors.

-Chuck Harris

Andy ZL3AG via Groups.Io wrote:

Hi Konstantinos,

Does this apply to the old style "industrial strength" silver tube tantalums, or just the later "blob" types?

If the -15V regulator is fed from the -40V start looking "downstream" of the -15V board. An overload on the -40V is highly unlikely to cause the -15V to fail. When the -40V fuse?fails without the -15V fuse going it's because the?"upstream" -40V fuse?has more normal load?so can fail first, protecting the -15V fuse.

Robert G8RPI.?

Hi Rick,

开云体育

I was wondering if anyone here knows where (besides the fine manual) there are examples of programming the 16C. I have a 15C and manual, and it seems like that manual has a lot more examples (plus there's the advanced functions handbook that has more). I've learned the 15C pretty effectively by sitting down with the manuals and working through examples and would like to do the same for the 16C.

I already get a lot of use out of my 16Cs for doing bit manipulations, pointer arithmetic, etc, but I want to get better at it and find clever ways to automate tasks that perhaps I've never even thought of. I could write Python all day to do the job much faster, no doubt, but it's a lot more satisfying on a keystroke programmable calculator. :)

Thanks!

Sean

_._,_._,_

---

You may want to check the program libraries at MoHPC The forums are also a good place to ask questions as it has a large audience of HP calculator users.

Paul.

Hi Group.
Could someone explain what is the function of "Enabled" and "Active" LED placed on the front panel of Z3805A?
According to Z3801A documentation, <<User-definable indicators labelled Enabled and Active. These can be turned on through the RS-422 port,>>
Ntothing else.anywhere.

Thank for any hints

I was wondering if anyone here knows where (besides the fine manual) there are examples of programming the 16C. I have a 15C and manual, and it seems like that manual has a lot more examples (plus there's the advanced functions handbook that has more). I've learned the 15C pretty effectively by sitting down with the manuals and working through examples and would like to do the same for the 16C.

I already get a lot of use out of my 16Cs for doing bit manipulations, pointer arithmetic, etc, but I want to get better at it and find clever ways to automate tasks that perhaps I've never even thought of. I could write Python all day to do the job much faster, no doubt, but it's a lot more satisfying on a keystroke programmable calculator. :)

Thanks!

Sean

On Mon, 15 Jul 2019, Terry Maurice wrote:

I have a full set of ROM files for 5343 that is a bigger brother of 5342.
Don't know if those would fit but most of those have 5432-xxx numbers. Here
are the text files I made when making copies:

=== Cut ===
HP 5343A 26.5GHz Microwave Counter

2 32x8 PROMs from 05342-60015 GPIB Board.

Board is the same between 5342A and 5343A
like most of other boards.

05342-80006 is U23, 05342-80007 is U26.

Signetics N82S23N devices (Russian K155PE3)

05342-80006 checksum: 0C34H
05342-80007 checksum: 0335H

Those are Open Collector devices.
=== Cut ===

=== Cut ===
HP 5343A 26.5GHz Microwave Counter
Only one UV-EPROM, p/n 05343-80003
No other info on original HP label.

Hitachi HN462532G device (== 2732)

Checksum: FA08H
=== Cut ===

I have a couple of 5343As, both refurbished, recapped and fully working,
with all options including totally useless DAC output :)

I do also have a 5342A somewhere that I keep as a parts donor, just in case
as most of the boards/parts are identical with 5343A so if you do really
need those (essentially only one 2732 as 2 PROMs are the same between the
two) 5342A ROMs I can read that and post a file.

Hello Kevin

Thanks for your reply.? I have been away for a few days of vacation and only getting to my email now.

My unit does have the HPIB option installed.? I took a look at the board and it is wedged in between the back of the case and the crystal oscillator.? I am not sure how to remove it, without removing the CO.? I will give the service manual a closer review to see how to do this.

I have tried to do the error checks but the unit does not respond, only the keyboard check seems to work and all the keys appear to be functioning.

I found in the service manual that a 1 on the display indicates that the A14U7 ROM is bad.? HP gives a part number for this as 1818-0706.? I think this ROM chip is now unavailable.? I could not locate it on the microprocessor board.? All chips are 1820.? Sounds like it may be toast for this unit.

Terry

On 7/11/2019 6:38 PM, Kevin Oconnor wrote:

Terry,
What options does your unit have? There were a lot available. Possibly one
option is hanging the control processor. Do you have the HPIB? It can hang
the processor. As option 11 I think you can remove it. It’s a process of
elimination. These counters are a bit older than the later reciprocal
counters with more powerful single chip solutions. So
debugging might be significantly different.
This counter has some self check features and error messages. What do
these report?
I it reports you have a starting point. If you can’t get any response
after the PO test, you will likely have to look at the internal
microprocessor bus. You indicated that the display does some PO check,
which to me says the micro is not dead but hung or waiting for something.
You may also have a bad ROM(s).
The manual explains how the systems work, must it is not for the faint of
heart!

Kevin

---
*
* KSI@home KOI8 Net < > The impossible we do immediately. *
* Las Vegas NV, USA < > Miracles require 24-hour notice. *
*

Hello Kevin

Thanks for your reply.? I have been away for a few days of vacation and only getting to my email now.

My unit does have the HPIB option installed.? I took a look at the board and it is wedged in between the back of the case and the crystal oscillator.? I am not sure how to remove it, without removing the CO.? I will give the service manual a closer review to see how to do this.

I have tried to do the error checks but the unit does not respond, only the keyboard check seems to work and all the keys appear to be functioning.

I found in the service manual that a 1 on the display indicates that the A14U7 ROM is bad.? HP gives a part number for this as 1818-0706.? I think this ROM chip is now unavailable.? I could not locate it on the microprocessor board.? All chips are 1820.? Sounds like it may be toast for this unit.

Terry

hi,

HP 8340a ?Synth. Sweeper ? keeps blowing A53 ?F2 fuse ?( -40V rail ??) ?on power On from Standby.

I am not certain what the -40 feeds, ? ( ?my .pdf schematics are very poor ?) ??
-- Could the ?-40V ?power ?the YIG or SYTM ?that often fails ?in the 8340 ??

Or ?a final RF amp failure ?

Or, are there some Tantalums that are problematic, in a specific area, ?to the 8340a ?

This is a new project, I have not had this it running so its state is questionable.
The front LED display will not turn on, ?and ?am testing the power supply voltages:

a) P/N: 08340-60005 A-2025-45 ? (A53 ?Neg. Reg. ? ? board ?) has 3 fuses on it & and an ?LM337 regulator.

The MRC is likely the same for both counters as it is hard coded according to HP Journal. The micro it self is a clone of a Mostek part. Don’t have the number offhand, but there is a Piggyback ROM version out there. They are rather rare and expensive. I know of no ROM image that is available for either counter. It can be read out but it is difficult.
I have never been able to confirm that the two counters use exactly the same code, though they have the same part number.
Old game restorers have the best info, as the Mostek part was used in a number of the early dedicated games.
Kevin

Sent from kjo iPhone

On 7/15/19 9:53 AM, garp6 wrote:

hi Tony,
Perfect, ?an excellent hand drawn schematic of the HP 85046 ?!

And here is a png cleanup of it, (with 1/8 the file size).

Tony,

sorry, typo error --?

that should have read:

hi Tony,

Perfect, ?an excellent hand drawn schematic of the HP 85046 ?!
?
{ my KB has some sticky keys }

thank you very much !!

rick

hi Orin,

Thank you for the schematics of the 85044a !

Yes, I should have known that the Ports 1 & 2 would have been blocked by capacitors !

thank you,

rick

hi John,

Thats ok, thank you for looking !

BTW, what did the parts come out of ?
- an attenuator or some APC-7 connector from ... ?

Just wondering, ?since am still searching for something adequate or modifiable !

thank you,
rick

hi Tony,

Perfect, ?an excellent hand drawn schematic of the HP 50046 !
? Of course, I should have know that it would be DC blocked.

thank you so much,

rick

Rick,
The ones I have are too short, about 21mm.
--John