HP 3325B Signal Generator Presentation

[psykok]

Hi,

I hunted for a long time until I found a replacement to my Waveteck FG3B Signal Generator.
The big issue was to found something that enters my budget more that my requirements.

Recently I scored a nice HP 3325B for 120€ on eBay.








The front panel was in realy durty condition but after cleaning it looks almost new




A quick look inside the beast





It's amazing how this Signal Generator works good.
I don't know exactly the age of this instrument but it's for sure around 15 year old.
I made some quick measurements and it's still in the specs, may be not 100% but that's 100x enough for me 



Currently the only issues I have with my new toy are that almost connections are located on the back and the room needed on my bench.

Regards,

Alex

[c4757p]

Definitely a nice instrument. My everyday-use function generator is its older brother the 3325A

I don't know exactly the age of this instrument but it's for sure around 15 year old.

About twenty-three, by the 1991 date code visible in the second-to-last picture on an IC.


The analog boards look almost identical to the 3325A. Digital's changed completely, though, except for the (IIRC) frequency generator board. It certainly looks like it doesn't have the vast mountain of 7400-series - the 3325A implements its entire GPIB transceiver as a 7400-series state machine!

[edpalmer42]

It's easy to determine the age of any piece of HP test equipment.  Look at the serial number.  The first four digits are the date code.  The year is represented as the number of years since 1960.  Yours looks like 2847.  If true, your unit was made in 1988, week 47.

Ed

[psykok]

It's easy to determine the age of any piece of HP test equipment.  Look at the serial number.  The first four digits are the date code.  The year is represented as the number of years since 1960.  Yours looks like 2847.  If true, your unit was made in 1988, week 47.

Ed

You are right the serial start with 2847
Thanks for the info, I was not aware of the HP serial format.


Alex

[c4757p]

Interesting. I can see more than one 1991 date code in that photo. I wonder if either that board was replaced at some point, or if those chips have a number that reads an awful lot like a date code but isn't...

[psykok]

Definitely a nice instrument. My everyday-use function generator is its older brother the 3325A

I don't know exactly the age of this instrument but it's for sure around 15 year old.

About twenty-three, by the 1991 date code visible in the second-to-last picture on an IC.


The analog boards look almost identical to the 3325A. Digital's changed completely, though, except for the (IIRC) frequency generator board. It certainly looks like it doesn't have the vast mountain of 7400-series - the 3325A implements its entire GPIB transceiver as a 7400-series state machine!

Yes they change the front panel and specilly the old hard buttons to the new soft one.

You can make a story only with the HP button true the age
For me it started with my calculator a HP 48GX and now it continue with my electronic instruments (8903a, 3325b ....)

[nctnico]

Yes they change the front panel and specilly the old hard buttons to the new soft one.

Good job on cleaning the front panel 
I really hate the old 'click' plastic buttons on HP equipment so much I don't buy it. The rubber buttons are a major improvement.

[psykok]

For cleaning I used isopropyl alcohol, it's the best solution to clean something without damaging the support.

[nctnico]

Be careful though; alcohol does dissolve some paint and plastics. I mostly use an equivalent of 'simple green' called stMarcs.

[Mandelbrot]

My function generator is an HP 3325A which, if that serial number dating works was made in 48th week 1977 which would make mine a very early unit. Nearly all my equipment is older than I am. I actually really like the clicky buttons on it except I had to open it up to slip some of the springs back in place. It's actually missing a couple; does anyone know if these flat steel springs are obtainable for a reasonable price?

[psykok]

Be careful though; alcohol does dissolve some paint and plastics. I mostly use an equivalent of 'simple green' called stMarcs.

I think you are talking about this StMarc :


If yes be careful this cleaning product contain Sodium Carbonate and can also dissolve paint and make spot on aluminium parts.

Isopropyl Alcohol is commonly used in all PCB and electronic cleaning solution and I never heard issue with plastics.
The only issue I had the last time was with a PCB varnish which turn from shiny to matt after cleaning the soldering residue.

[nctnico]

I mostly use this stuff:
http://static.webshopapp.com/shops/010050/files/002551545/260x225x2/st-marc-verfreiniger-en-ontvetter.jpg

If that fails I switch to (bio) ethanol.

[Andy Watson]

It's actually missing a couple; does anyone know if these flat steel springs are obtainable for a reasonable price?

I doubt that the springs will be available. It might be possible to fashion replacements out of shim-steel (or feeler gauge) material.

[MadTux]

It's possible to make them from 0.05mm spring steel sheet. Just look for real hard 0.05mm spring steel (not soft stainless "spring" steel) on ebay and then cut them with scissors.

[lowimpedance]

Actually the feeler gauge stock is perfect if you get the correct thickness, (Starrett comes to mind, but others make too).