Parts needed for HP8559A


Willis, MJ &#92;(Michael&#92;) <m.j.willis@...>
 

I was lucky enough to pick up an HP8559A analyser at the Round Table. It has several faults though, mostly probably due to poor switch and relay contacts. The one I am working on at the moment is the frequency display. This uses the LD120CJ and LD121CJ. The Analogue LD120CJ chip has definitely failed, it gets very hot, I think because of a fault in the power supply from the original mainframe. I don't know if the LD121CJ is working or not.
 
Both of these are obsolete. Does anyone have any spares, or more likely a dead 8559A with a still working frequency display?
 
Mike


Chris G8BKE
 

This company stocks some obsolete HP components.

http://www.sphere.bc.ca/test/

73 de Chris G8BKE

Web Site:-
http://www.qsl.net/g8bke/index.html





Both of these are obsolete. Does anyone have any spares, or more likely
a dead 8559A with a still working frequency display?

Mike


david wrigley <davidwrigley@...>
 

Hi Mike

 

I don’t have any spares but they look like easy parts to get alternatives for

 

In the Farnell Cat There is an ICL135 (41/2 digit ADC) which looks like a possible for the LD120

The LD121 is a driver – not sure of the polarity or of any limiting resistance you may need for LED drives.

 

I have used alternatives for HP parts before for displays on the HP436A and sometimes HP have bits in like limiting resistors which alternative parts don’t have. To get round this I have made a plug-in replacement by using a header with the replacement IC and the extra bits attached.

 

Best of luck

 

David G6GXK

 

 


From: ukmicrowaves@... [mailto:ukmicrowaves@...] On Behalf Of Willis, MJ (Michael)
Sent: 05 December 2006 08:00
To: ukmicrowaves@...
Subject: [ukmicrowaves] Parts needed for HP8559A

 

I was lucky enough to pick up an HP8559A analyser at the Round Table. It has several faults though, mostly probably due to poor switch and relay contacts. The one I am working on at the moment is the frequency display. This uses the LD120CJ and LD121CJ. The Analogue LD120CJ chip has definitely failed, it gets very hot, I think because of a fault in the power supply from the original mainframe. I don't know if the LD121CJ is working or not.

 

Both of these are obsolete. Does anyone have any spares, or more likely a dead 8559A with a still working frequency display?

 

Mike


Peter Day <microwaves@...>
 

Willis, MJ (Michael) wrote:
I was lucky enough to pick up an HP8559A analyser at the Round Table.
I never saw that! I could have done with it for spares.

I didn't see the 47GHz preamp that some bought either!

Next year I'll be free to trawl the fleamarket instead of doing UKuG duties...watch out folks:-)

Peter, G3PHO


Willis, MJ &#92;(Michael&#92;) <m.j.willis@...>
 

Thanks David,
 
The ICL135 is a very different IC, it is a modern replacement for the LD120 LD121 pair, which could be used if I designed a new PCB etc. I would rather avoid that if I can, I might as well replace the whole display at that point with an LCD meter.
 
Mike 
 
 


From: ukmicrowaves@... [mailto:ukmicrowaves@...] On Behalf Of david wrigley
Sent: 05 December 2006 10:13
To: ukmicrowaves@...
Subject: RE: [ukmicrowaves] Parts needed for HP8559A

Hi Mike

I don’t have any spares but they look like easy parts to get alternatives for

In the Farnell Cat There is an ICL135 (41/2 digit ADC) which looks like a possible for the LD120

The LD121 is a driver – not sure of the polarity or of any limiting resistance you may need for LED drives.

I have used alternatives for HP parts before for displays on the HP436A and sometimes HP have bits in like limiting resistors which alternative parts don’t have. To get round this I have made a plug-in replacement by using a header with the replacement IC and the extra bits attached.

Best of luck

David G6GXK


From: ukmicrowaves@yahoogroups.com [mailto:ukmicrowaves@yahoogroups.com] On Behalf Of Willis, MJ (Michael)
Sent: 05 December 2006 08:00
To: ukmicrowaves@yahoogroups.com
Subject: [ukmicrowaves] Parts needed for HP8559A

I was lucky enough to pick up an HP8559A analyser at the Round Table. It has several faults though, mostly probably due to poor switch and relay contacts. The one I am working on at the moment is the frequency display. This uses the LD120CJ and LD121CJ. The Analogue LD120CJ chip has definitely failed, it gets very hot, I think because of a fault in the power supply from the original mainframe. I don't know if the LD121CJ is working or not.

Both of these are obsolete. Does anyone have any spares, or more likely a dead 8559A with a still working frequency display?

Mike


Willis, MJ &#92;(Michael&#92;) <m.j.willis@...>
 

Very useful company - but out of stock. If I want $250 worth, I can get
them.

Mike

-----Original Message-----
From: ukmicrowaves@yahoogroups.com [mailto:ukmicrowaves@yahoogroups.com]
On Behalf Of CT
Sent: 05 December 2006 10:12
To: ukmicrowaves@yahoogroups.com
Subject: Re: [ukmicrowaves] Parts needed for HP8559A


This company stocks some obsolete HP components.

http://www.sphere.bc.ca/test/

73 de Chris G8BKE

Web Site:-
http://www.qsl.net/g8bke/index.html





Both of these are obsolete. Does anyone have any spares, or more likely
a dead 8559A with a still working frequency display?

Mike





Yahoo! Groups Links


Grant Hodgson <grant@...>
 

Willis, MJ (Michael) wrote:

The ICL135 is a very different IC, it is a modern replacement for the LD120 LD121 pair, which could be used if I designed a new PCB etc. I would rather avoid that if I can, I might as well replace the whole display at that point with an LCD meter.
Which is probably the easiest option - the frequency readout is simply a measure of the voltage on the oscillator control line - a PIC could do the A-D, some simple maths and either drive the existing LED display or a new LCD.

However, for the purists there is a Yahoo group for those interested in operating, collecting, restoring and maintaining HP equipment :-

http://tech.groups.yahoo.com/group/hp_agilent_equipment/

For anybody who likes this sort of thing there is a lot of information available from some real HP experts.

regards

Grant


Willis, MJ &#92;(Michael&#92;) <m.j.willis@...>
 

Yes Grant - it is looking that way. Nobody has admitted to having a broken one.
 
Unfortunately, the tuning voltage measured is 0 to -4V for DC-20GHz. This means I need to isolate the meter supply with a DC-DC module if I am going to use a simple cheap LCD meter and not have a minus sign. They do do single round hole fixing ones now though, so it would be easy to fit without modifying the panel. Most LCDs are 3 1/2 digit though I doubt 4 1/2 digits are justified, I think this is just so the reading is in MHz. A little optimistic for a free running microwave VCO.
 
I also thought about using a frequency counter on the LO - the problem is there is an IF offset, or rather two IF offsets and you need to keep track of which harmonic the mixer is set to favour. Then there is ensuring it averages correctly across a wide sweep. That would need a PIC with some tricky code.

From: ukmicrowaves@... [mailto:ukmicrowaves@...] On Behalf Of Grant Hodgson
Sent: 06 December 2006 08:34
To: ukmicrowaves@...
Subject: Re: [ukmicrowaves] Parts needed for HP8559A

Willis, MJ (Michael) wrote:

>
> The ICL135 is a very different IC, it is a modern replacement for the
> LD120 LD121 pair, which could be used if I designed a new PCB etc. I
> would rather avoid that if I can, I might as well replace the whole
> display at that point with an LCD meter.

Which is probably the easiest option - the frequency readout is simply a
measure of the voltage on the oscillator control line - a PIC could do
the A-D, some simple maths and either drive the existing LED display or
a new LCD.

However, for the purists there is a Yahoo group for those interested in
operating, collecting, restoring and maintaining HP equipment :-

http://tech.groups.yahoo.com/group/hp_agilent_equipment/

For anybody who likes this sort of thing there is a lot of information
available from some real HP experts.

regards

Grant


Geoff Blake <geoff@...>
 

Mike,

Sorry, I have come late to this, b*oo$y Yahoo decided that all my
email was bouncing because some spam crept onto one of their lists
and Demon bounced it. Grrr!

If it is of any help I have a "parts" 8565A at work. I believe
that it still has its frequency display which may be compatible
(it works on the same basis).

If so, you would be welcome.

Geoff

--
Geoff Blake G8GNZ located near Chelmsford, Essex, U.K.
Please reply to: geoff (at) palaemon (dot) co (dot) uk
Using Linux on Intel & Linux or NetBSD on Sun Sparc platforms

Please avoid sending me Word or PowerPoint attachments.
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Willis, MJ &#92;(Michael&#92;) <m.j.willis@...>
 

Thanks Geoff - It may be just the job, I don't have any info but I would think it might be OK from looking at a photo of one.  I think the 8565 was an upgrade of the 8559 with a new mainframe.
 
I am still in Oxford of course..
 
Mike


From: ukmicrowaves@... [mailto:ukmicrowaves@...] On Behalf Of Geoff Blake
Sent: 06 December 2006 10:10
To: ukmicrowaves@...
Subject: RE: [ukmicrowaves] Parts needed for HP8559A

Mike,

Sorry, I have come late to this, b*oo$y Yahoo decided that all my
email was bouncing because some spam crept onto one of their lists
and Demon bounced it. Grrr!

If it is of any help I have a "parts" 8565A at work. I believe
that it still has its frequency display which may be compatible
(it works on the same basis).

If so, you would be welcome.

Geoff

--
Geoff Blake G8GNZ located near Chelmsford, Essex, U.K.
Please reply to: geoff (at) palaemon (dot) co (dot) uk
Using Linux on Intel & Linux or NetBSD on Sun Sparc platforms

Please avoid sending me Word or PowerPoint attachments.
See <http://www.gnu.org/philosophy/no-word-attachments.html>
----------------------------------------------------------

This E-mail and any attachment(s) are strictly confidential
and is intended solely for the addressee(s). If you are not the
intended recipient please notify at)palaemon.co.uk>
and the sender by return and permanently delete the message.

You may not disclose, forward or copy this E-mail or any of its
attachments to any third party without the prior consent of the
sender.

----------------------------------------------------------


Geoff Blake <geoff@...>
 

On Wed, 6 Dec 2006, Willis, MJ (Michael) wrote:

Thanks Geoff - It may be just the job, I don't have any info but I would
think it might be OK from looking at a photo of one. I think the 8565
was an upgrade of the 8559 with a new mainframe.

I am still in Oxford of course..
OK Mike, if you can let me know the part number that you want,
I'll compare it with what I have.

Geoff
--
Geoff Blake G8GNZ located near Chelmsford, Essex, U.K.
Please reply to: geoff (at) palaemon (dot) co (dot) uk
Using Linux on Intel & Linux or NetBSD on Sun Sparc platforms

Please avoid sending me Word or PowerPoint attachments.
See <http://www.gnu.org/philosophy/no-word-attachments.html>
------------------------------------------------------------------------------

This E-mail and any attachment(s) are strictly confidential
and is intended solely for the addressee(s). If you are not the
intended recipient please notify <postmaster(at)palaemon.co.uk>
and the sender by return and permanently delete the message.

You may not disclose, forward or copy this E-mail or any of its
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Geoff Blake <geoff@...>
 

On Wed, 6 Dec 2006, Willis, MJ (Michael) wrote:

Thanks Geoff - It may be just the job, I don't have any info but I would
think it might be OK from looking at a photo of one. I think the 8565
was an upgrade of the 8559 with a new mainframe.
Mike, I have just compared the man pages on the unit as fitted to
an 8565A and the unit as fitted to the 8559A and they are in no
way related. Both units use an "electronics" board as well as a
display board and the design of the 8565A board is primarily TTL
based.

So I don't think that it will be of use to you

Sorry to get your hopes up.

Geoff
--
Geoff Blake G8GNZ located near Chelmsford, Essex, U.K.
Please reply to: geoff (at) palaemon (dot) co (dot) uk
Using Linux on Intel & Linux or NetBSD on Sun Sparc platforms

Please avoid sending me Word or PowerPoint attachments.
See <http://www.gnu.org/philosophy/no-word-attachments.html>
------------------------------------------------------------------------------

This E-mail and any attachment(s) are strictly confidential
and is intended solely for the addressee(s). If you are not the
intended recipient please notify <postmaster(at)palaemon.co.uk>
and the sender by return and permanently delete the message.

You may not disclose, forward or copy this E-mail or any of its
attachments to any third party without the prior consent of the
sender.

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