Agilent 54600 Series Quiet Fan Replacement? - Page 1
Forum section: electronics / testgear

author: wirewrap
author_rank: Newbie
timestamp: December 16, 2017, 04:27:13 pm
content: I have had my Agilent 54622D scope for over a year now and Im just about able to stand the sound of the thing, however as I am trying tomod my 66312A to be more quietI thought I would go down the same route with this.The scope uses an80mm Panaflo 12V fanwith some rather high specs (high RPM and very high static pressure).So in a similar vain to my PSU, I am wondering of I can replace this noisy clunky fan with something considerably more quiet.I am considering using anoctua 80mm fanas a reliable replacement, however even their most powerful models of that size only have half the static pressure.With the PSU I can guess pretty easily what it will need, its just a big hunk of metal cooling about 40W, but with the scope its a lot more complex, with a huge mainboard to cool (AFAIK the megazoom ASICs get very hot) so I am less confident.Has anyone else had success with this?Thank you

author: dazz1
author_rank: Frequent Contributor
timestamp: September 18, 2023, 06:48:45 am
content: HiI replaced the factory fan with a Noctua NF-A8 FLX.What a difference. Definitely worth the trouble. The fan is now just a quiet murmur.This is how I fitted it.The Noctua box includes a 3 pin connector socket adapter that fits the plug on the fan. At the other end is an old fashioned Molex 4 pin connector, for 12V.I cut off the Molex connector.I disconnected the factory cable for the factory fan. The HP PCB end includes a 2-pin connector with IDC pins. I prized off the wires from the pins to leave a bare connector.I then carefully fitted the two wires from the Noctua cable (that had the Molex connector cut off).The result was a short adapter cable (~2cm) that had the HP 2-pin pcb connector and the 3-pin fan socket.Now the Noctua fan plugs directly into the short adapter cable.The fan was a perfect fit. I used M4x12 screws, finger tight with lock-tite applied.This all worked perfectly.In order to compensate for the reduced fan flow, I am considering 3D printing 5mm risers to place under the feet of the HP54645 scope to increase the gap for air flow.

author: dazz1
author_rank: Frequent Contributor
timestamp: September 20, 2023, 05:01:19 am
content: HiOK so I went ahead and made two spacer feet that simply slide over the factory molded front feet and lock in place. The feet lift the scope a few millimeters to increase the space for exhaust cooling air to escape. The only exit for cooling air is a grill in the base of the enclosure.As always, I try and make my mods look like they are factory made. The new feet are close to the factory colour so it is not obvious the feet are fitted. No screws, no holes, no modifications to the enclosure and all completely reversible.I included a shallow relief for gluing on a piece of rubber roofing material. The rubber will provide some extra grip and reduce noise transmission by at least a few femtodecibles.Just in case someone wants to do the same mod, I have also attached the 3D file of the design. I printed with PETG.On a scale from brilliant to useless, this mod definitely leans to the useless side, but I got to design and make something.

author: tautech
author_rank: Super Contributor
timestamp: September 20, 2023, 07:36:14 am
content: Quote from: dazz1 on September 20, 2023, 05:01:19 amDazz, pop a post here so your work is not lost in time to come:https://www.eevblog.com/forum/testgear/replacement-knobs-feet-and-fittings-for-test-equipment/

author: dazz1
author_rank: Frequent Contributor
timestamp: September 20, 2023, 08:28:22 am
content: Quote from: tautech on September 20, 2023, 07:36:14 amOK did that here:https://www.eevblog.com/forum/testgear/replacement-knobs-feet-and-fittings-for-test-equipment/msg5069677/#msg5069677I didn't know that topic existed. I could see it being really useful for restorers.

author: Ricotjuh
author_rank: Newbie
timestamp: December 21, 2023, 04:20:32 pm
content: Thanks for the clear explanation. I followed your steps and it works perfectly. I did have to file away some of the plastic. Otherwise I could not screw the fan properly onto the mounting points. But other than that it works perfectly.