EMRFD Message Archive 7539

Message Date From Subject
7539 2012-06-19 17:17:32 Phil Sittner Vector voltmeter useage
Gentlemen-

I stumbled across a pristine H-P 8405A vector voltmeter at a recent swap meet and it followed me home. There have been references to Bill Carter using one of these as he works magic into his designs and would like any suggestions as to how to use this vintage piece of equipment and where it's use aids in circuit development. All thoughts are welcome. It should be mentioned that the shack also contains an N2PK VNA, and a DG8SAQ VNWA and a just completed Scotty's Spectrum Analyzer.

Phil
kd6rm

[Non-text portions of this message have been removed]
7540 2012-06-19 21:23:32 William Carver Re: Vector voltmeter useage
Mine came home from W4ZCB....who picked it up for a song at Dayton many
years ago. He never used it. I calibrated it, repaired some things, got
a spare parts doner for $5 at a Colorado swapmeet. Now it seems to work
but I have not used it for anything yet.

Bill




On Tue, 2012-06-19 at 17:17 -0700, Phil Sittner wrote:
>
> Gentlemen-
>
> I stumbled across a pristine H-P 8405A vector voltmeter at a recent
> swap meet and it followed me home. There have been references to Bill
> Carter using one of these as he works magic into his designs and would
> like any suggestions as to how to use this vintage piece of equipment
> and where it's use aids in circuit development. All thoughts are
> welcome. It should be mentioned that the shack also contains an N2PK
> VNA, and a DG8SAQ VNWA and a just completed Scotty's Spectrum
> Analyzer.
>
> Phil
> kd6rm
>
> [Non-text portions of this message have been removed]
>
>
>
>
>
7541 2012-06-19 23:32:54 Kerry Re: Vector voltmeter useage
I have one; a very nice & useful instrument, I used it quite a lot until I got my N2PK and DG8SAQ VNAs.

There is a manual on BAMA; http://bama.edebris.com/manuals/hp/8405a/

The 8405A was featured in the HP Journal in May 1966; http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/hpjindex.html

Incidentally, the HP Journals are wonderful reads; I have downloaded many of them.

I also got the HP11570A accessory kit but didn't use it much. Mine was missing the HP10218A probe-BNC adaptors so I made some;

http://i45.tinypic.com/4to9xi.jpg

from BNCs & brass tube; they were very useful.

I have a copy of an article on using the 8405 to measure complex Z; PM me if you would like a copy.

The 8405 can be used as an "ordinary" RF voltmeter if phase information is not required; it is very sensitive and accurate.

Kerry VK2TIL.
7542 2012-06-20 06:56:02 Chris Trask Re: Vector voltmeter useage
>
>I stumbled across a pristine H-P 8405A vector voltmeter at a
> recent swap meet and it followed me home. There have been
> references to Bill Carter using one of these as he works
> magic into his designs and would like any suggestions as to
> how to use this vintage piece of equipment and where it's
> use aids in circuit development. All thoughts are welcome.
> It should be mentioned that the shack also contains an N2PK
> VNA, and a DG8SAQ VNWA and a just completed Scotty's
> Spectrum Analyzer.
>

The 8405A makes a dandy instrument for use with my crystal test set. Using the A/B function you can measure the ratio directly for measuring the crystal series resistance.

Chris
7543 2012-06-20 08:23:41 William Carver Re: Vector voltmeter useage
Thanks for 8405A links (and some motivation) Kerry
W7AAZ
7544 2012-06-20 14:44:10 Kerry Re: Vector voltmeter useage
It's quite some time since I read the HP Journal article; I did so this morning.

I had forgotten that it has a detailed description of the things that can be done with the 8405A.

I also remembered the existence of HP AN77-3;

www.hpmemory.org/an/pdf/an_77-3.pdf

I have always liked the testbench photo in AN77-3;

http://i50.tinypic.com/97pd1g.jpg

A wonderful view of the "olden days" way of doing things.

Kerry VK2TIL.
7545 2012-06-20 15:03:38 Lasse Re: Vector voltmeter useage
Just saved a 8405A from beeing scrapped... now will put it on the bench
along with my 606 and my 608F. :)

/Lasse SM5GLC

Kerry skrev 2012-06-20 23:44:
> It's quite some time since I read the HP Journal article; I did so this morning.
>
> I had forgotten that it has a detailed description of the things that can be done with the 8405A.
>
> I also remembered the existence of HP AN77-3;
>
> www.hpmemory.org/an/pdf/an_77-3.pdf
>
> I have always liked the testbench photo in AN77-3;
>
> http://i50.tinypic.com/97pd1g.jpg
>
> A wonderful view of the "olden days" way of doing things.
>
> Kerry VK2TIL.
>
>
>
7546 2012-06-20 17:11:56 Phil Sittner Re: Vector voltmeter useage
Kerry-

It was great to get your message. The unit that followed me home had the complete originally accessory kit with it. And in digging around the web I found application note 77-3 at the H-P Memory site. Agilent also has made available the user guide for a later model, 8508. And Chris Trask finds it helpful with his crystal sets. Just alot of more fun stuff to explore. Thanks again for taking the time to respond.

Phil
kd6rm
----- Original Message -----
7547 2012-06-20 17:14:26 Phil Sittner Re: Vector voltmeter useage
Bill-
Thanks for the response. I've found a little informati
7548 2012-06-20 18:40:49 Kerry Re: Vector voltmeter useage
7549 2012-06-20 19:39:29 Phil Sittner Re: Vector voltmeter useage
Kerry-

Like you, I fell victim to the ease of the VNA for crystal parameter measurement. The same path was followed early, G3UUR, 3dB etc but you just can't beat testing 100 crystals and have them drop nicely into an excel spread sheet for sorting. None the less, the 8405A has me intrigued, especially for some amplifier and filter applications. Keep up the good work.

Phil
kd6rm
----- Original Message -----