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Products => Test Equipment => Topic started by: xwarp on May 26, 2017, 11:51:51 pm

Title: HP 8591e with very dim crt... worth buying?
Post by: xwarp on May 26, 2017, 11:51:51 pm
Local sale for $250. It needs a new crt, which I see can be had for $200. Checked it out and it appears that it should be fine once a new crt is put in.

Being 75ohm, that is ok by me.

Thoughts?
Title: Re: HP 8591e with very dim crt... worth buying?
Post by: james_s on May 28, 2017, 02:05:19 am
I'd jump on that if it were local to me. Might be able to revive the CRT, I've had reasonable luck with my Sencore CRT tester rejuvenating old tubes. Doesn't always work but it's worth a shot.
Title: Re: HP 8591e with very dim crt... worth buying?
Post by: xwarp on May 28, 2017, 03:17:39 am
Turns out that the intensity pot knob was the issue although the crt does have significant burn in, it's still bright and clear.
Title: Re: HP 8591e with very dim crt... worth buying?
Post by: james_s on May 28, 2017, 05:04:51 am
I love an easy fix like that. Sounds like you got a heck of a deal, some burn is pretty common, it could easily last thousands of hours more.
Title: Re: HP 8591e with very dim crt... worth buying?
Post by: deepskyridge on May 28, 2017, 02:20:55 pm
I bought one a while back with a dead display. I used the video output on the back to verify operation.

I got a new (NOS) from the following seller:

http://www.ebay.com/itm/1-Qty-LOT-NEW-HP-Agilent-2090-0539-CRT-Display-Section-for-8590-Spectrum-Analyze-/262968678639?hash=item3d3a2798ef:g:oEYAAOSw~FNUY7~q (http://www.ebay.com/itm/1-Qty-LOT-NEW-HP-Agilent-2090-0539-CRT-Display-Section-for-8590-Spectrum-Analyze-/262968678639?hash=item3d3a2798ef:g:oEYAAOSw~FNUY7~q)

Easy fix, unit works great. Don't forget to change the battery in the unit.

Gary
Title: Re: HP 8591e with very dim crt... worth buying?
Post by: NavyBOFH on May 28, 2017, 04:25:22 pm
As the above poster said - the CRT kits are pretty cheap and are all new or "good stock". I have plenty of 856x series analyzers with good screens but other blown components we use as spare parts cadavers for our working units.

That being said - I also hear the LCD upgrade kits are worth every penny if you want to spend around $500 on a display. I am just waiting for a CRT to die on a piece of equipment to give me a reason to try and order one.
Title: Re: HP 8591e with very dim crt... worth buying?
Post by: carl_lab on May 28, 2017, 05:38:19 pm
Quote from: deepskyridge on May 28, 2017, 02:20:55 pm
Don't forget to change the battery in the unit.
Where is the battery located?
I repaired our 8591E a few weeks ago, but I couldn't find the battery.
Title: Re: HP 8591e with very dim crt... worth buying?
Post by: xwarp on May 28, 2017, 06:04:30 pm
Quote from: carl_lab on May 28, 2017, 05:38:19 pm
Quote from: deepskyridge on May 28, 2017, 02:20:55 pm
Don't forget to change the battery in the unit.
Where is the battery located?
I repaired our 8591E a few weeks ago, but I couldn't find the battery.

The manual I have states that it's on the A16A1 memory board.
Title: Re: HP 8591e with very dim crt... worth buying?
Post by: MarkL on May 28, 2017, 08:18:51 pm
There's a procedure in the 895x service manual to backup the cal contstants.  You might want to do this before replacing the battery, just in case something slips.

Depending on the age of the unit, it could be either a cylindrical lithium cell on the main board on the bottom near the back, or a large lithium coin cell on the memory card.
Title: Re: HP 8591e with very dim crt... worth buying?
Post by: carl_lab on May 28, 2017, 09:20:37 pm
Quote from: MarkL on May 28, 2017, 08:18:51 pm
There's a procedure in the 895x service manual to backup the cal contstants.  You might want to do this before replacing the battery, just in case something slips.

Good point.
AFAIK a new calibration is not exactly what I'd call low-cost...