Agilent Keysight 33500B Repair - looking for photos - Page 1
Forum section: electronics / testgear

author: salvagedcircuitry
author_rank: Regular Contributor
timestamp: March 17, 2023, 04:56:47 pm
content: Hi. I'm in the middle of a 33509b waveform generator repair. I snagged the unit for a reasonable price and it seems that a previous technician was a little tip happy with his coffee.Besides the very sticky residue all over the front panel PCB, I noticed that the CMOS battery area looked a bit compromised.There looks to be a voltage sense resistor missing near the positive 2032 battery trace and the bottom half of the battery tray has sheared off the board.If anyone has high resolution photos of the front panel PCB, I would be very grateful.Double points if anyone knows what the value of that resistor is.Many Thanks!

author: Brandy
author_rank: Newbie
timestamp: March 27, 2024, 02:06:53 pm
content: picture 1

author: Brandy
author_rank: Newbie
timestamp: March 27, 2024, 02:09:35 pm
content: picture 2when i measure the resistor (the print on it says 53A) i see 348 ohms.I think the value is not 100% correct as I measured the resistor in fitted position and battery in place.

author: PA0PBZ
author_rank: Super Contributor
timestamp: March 27, 2024, 02:50:04 pm
content: Quote from: Brandy on March 27, 2024, 02:09:35 pmI think you measured the resistor correctly:http://www.marsport.org.uk/smd/res.htm

author: salvagedcircuitry
author_rank: Regular Contributor
timestamp: September 22, 2024, 06:24:02 am
content: Holy crap! Thanks a ton! I somehow didn't get updated on this thread. @brandy & @PA0PBZ, you guys are the best!Since initial teardown, I toothbrush cleaned the main PCB and front panel with IPA and tested the unit. The 40khz ultrasonic I had at the time would have damaged some mems parts and oscillators, so I opted for the tooth brush method. It did not do that great of a job but I was able to get the scope to boot and control it over ethernet, which is kind of nuts. The waveform generator only showed a white screen when I got it.Later on, I grabbed a 132kHz ultrasonic and cleaned the front panel. It came out spotless and the waveform gen is actually responsive, the LCD works and the front button panel works, but unfortunately I damaged component U704 while blowing the alcohol off the board from ultrasonically cleaning. I should have regulated the air output.U704 is deceiving and looks like a big ol SMT inductor, especially with the large pads on either side, but I should have known better since it's U### not L### component silkscreen. The lid blew off and what looks to be an oscillating bit of crystal on a thin metal sheet popped out. I may be able to solder it back together but I highly doubt it'll ever work right again. :'(Does anyone know what oscillator company makes part U704? The logo looks similar to the micron logo, but micron does not make oscillators. I'm going to try and hunt the part down.I circled the part in red. Thanks tremendously!

author: squadchannel
author_rank: Frequent Contributor
timestamp: September 22, 2024, 09:45:50 am
content: U704 is Murata's piezo buzzer.PKLCS1212E40A1-R1, but there are three types with different frequencies.4.0KHz:PKLCS1212E40A1-R1 (U704)2.4KHz:PKLCS1212E24A0-R12.0KHz:PKLCS1212E20A0-R1

author: salvagedcircuitry
author_rank: Regular Contributor
timestamp: September 22, 2024, 04:33:34 pm
content: Woah there, how did you find this??? Thanks tremendously!I have hopes of getting this waveform gen back up and running properly again. Woot woot.Thanks a ton