Teardown & Repair of an Agilent 8562E 30Hz - 13.2GHz Spectrum Analyzer - Page 1
Forum section: electronics / testgear

author: Hugoneus
author_rank: Frequent Contributor
timestamp: November 24, 2017, 04:33:20 pm
content: You can watch the video here: [41 Minutes]youtu.be/Pep-cgXjTNoMore videos at The Signal Path:The Signal Pathwww.TheSignalPath.comwww.YouTube.com/TheSignalPathwww.Patreon.com/TheSignalPath

author: Hydron
author_rank: Super Contributor
timestamp: November 24, 2017, 09:10:51 pm
content: The YTO teardown was especially interesting, thanks.And I feel the pain of killing FETs by forgetting the gate driver - leaving out the gate resistor does the same thing! Even saw it die on a thermal camera, but wasn't quick enough to save it.

author: Hugoneus
author_rank: Frequent Contributor
timestamp: November 27, 2017, 08:06:10 pm
content: Quote from: Hydron on November 24, 2017, 09:10:51 pmThe failure happened essentially instantly. There was no way to save it. The fuse blew and that didn't help to save the devices. The fuse (even though it was fast acting) was not fast enough.

author: rhb
author_rank: Super Contributor
timestamp: November 28, 2017, 12:41:18 am
content: Thank you. Very nice. Though I do wish you'd gone into more detail about the alignment process. Perhaps in a separate video?

author: texaspyro
author_rank: Super Contributor
timestamp: November 28, 2017, 01:17:34 am
content: Quote from: Hugoneus on November 27, 2017, 08:06:10 pmThe FETs did exactly what they were supposed to do... protect the fuse.

author: HighVoltage
author_rank: Super Contributor
timestamp: November 28, 2017, 10:03:07 am
content: Great repair video again.It is great to follow your thought process.Thanks!I have one of these SA and hope that I don't have to open it, ever.

author: CNe7532294
author_rank: Regular Contributor
timestamp: November 29, 2017, 09:21:57 am
content: Awesome video. There were several things to like here. Not only did you acknowledge your mistake but you thoroughly explained what happened. Another thing is opening up the YIG. Even though I've opened one of these myself I was kinda surprised by the different ceramic circuit used. Mines was more square looking while yours is more rectangular. Also had "LEYO" marking instead of EYO. Essentially it looks like this (not my pic but from Luis Cupido).Still, HP/Agilent/Keysight's secret is that they reuse some of the same parts on different units. So your assumption is correct that the YIG, minus the bias PCB and maybe hardware (like standoffs and screws) on top, is the same despite the different part number. They probably made it a little different due to improvement to power and reliability. Currently, I'm trying to replace a low band assembly's removable ceramic amplifier. I have found at least 6 different unit which uses this assembly. From VNAs to Tracking Gens to a standlone RF amplifier unit. I'm hoping to get the amplifier unit because I will end up repurposing it as a testing rig for the ceramic amplifier used in any of these units. On a RYTHM that I have that is "dead" (actually YIG balls need realignment). Kinda like this picture here (also from Luis). I can find a replacement from a more modern one given that Agilent themselves put a modern part number label on a refurbished unit. This part however will be expensive or labor intensive to replace or realign/repair. Its the one thing you hope it will not fail.I also like how you keep repairing 856#X (#= 0-5; X=A,B,E,or EC) series spectrum analyzers. These are great analyzers to start off with. I do agree that taking the power supply out is a nightmare. The way I've done it is to face the analyzer downward instead of its side. (see my pic here) I recently had to do this because those 250V RIFA X filter capacitors blew. Please inspect those for any signs of cracking. Its not fun when they blow up. They're claimed to be self extinguishing if they start burning but I'd rather not test that.About this pic, if you're wondering why in the world I was attempting a repair with a carpet floor on a party table, that is because my garage was under the threat of flooding during Hurricane Harvey (fortunately I never flooded out). Those caps couldn't have failed at a worse time. Luckily I have spare parts and a back up unit. Used the unit to listen in on any emergency chatter and help with rescue by detecting common signals.