Hp Agilent Keysight 34401a  VFD replacement at 30$ usd each - Page 1
Forum section: electronics / testgear

author: coromonadalix
author_rank: Super Contributor
timestamp: March 20, 2019, 10:45:47 am
content: Just to let you know EEvblog membersBought 2 of them here :https://www.aliexpress.com/item/1PC-Repalcement-NEW-for-HP-AGILENT-34401A-Display-VFD-vacuum-Fluorescence-Display/32963797699.html?spm=a2g0s.9042311.0.0.3da24c4di7RsBFVery well priced at30$ usd, very bright (with the windows bezel removed and cleaned up) no missing sections. Took 35 days to receive them in Canada.The only replacement from Keysight with the pcb included for a mere 200$ usdand they dont have many stock left ....I saw many vfd substitutes of them higher priced on Fleabay.When you power the meter, keep the shift key pressed, it will light all the display segments ... and do the self tests after you release the shift key

author: NoisyBoy
author_rank: Frequent Contributor
timestamp: March 20, 2019, 06:23:38 pm
content: After reading a number of inconsistent quality of replacement Chinese VFDs, it is nice for you to share a source to get a good VFD. It would be great if you can take some pictures to share it with the community.It certainly is a lot cheaper to just replace the dim display (especially for the older 34401A on Rev 1 display boards), than the entire display front end.One of my 34401A was getting inconsistent segment brightness due to burn-in in 5 digit mode. In my case, I keep all my equipment fully Keysight/Agilent original, so I called up my Keysight rep and ordered a display front end under my Keysight account, it was $150 if I recall correctly. The new board is Rev 3.But it is always nice to know that there is an alternative, thanks for sharing.BTW, if I don't want to deal with warm-up and had to do a number of measurements scattered over a long period of time, now I just turn the display off when I am not using it.Quote from: coromonadalix on March 20, 2019, 10:45:47 am

author: NoisyBoy
author_rank: Frequent Contributor
timestamp: March 20, 2019, 06:37:44 pm
content: BTW, are your units the same as pictured? I noticed it is the Japanese itron with the circular/needle pin with the black insulation..They were used many years ago in the Agilent Made in the U.S.A. display front-end, before Agilent switched to the Samsung VFD and moved manufacturing to MalaysiaIt would be a very good buy if what you get is the original itron parts.

author: coromonadalix
author_rank: Super Contributor
timestamp: March 20, 2019, 08:54:26 pm
content: i'll send some photos this week while i hold the shift key and the back of the vfd, i saw some markingsThey are not itron marked, nor samsung

author: Cubdriver
author_rank: Unknown
timestamp: March 21, 2019, 07:42:53 am
content: Thanks for the tip!-Pat

author: coromonadalix
author_rank: Super Contributor
timestamp: March 21, 2019, 05:12:33 pm
content: here ya go, the pins are at least 3/4 inch long, the overall glass thickness is 0.5 mm thicker than the original vfd ... the white sticker has been partially thorn, it came like thismarkings :zejhiang feidafd33-1201 135*23*37

author: NoisyBoy
author_rank: Frequent Contributor
timestamp: March 22, 2019, 07:46:36 pm
content: Thank you so much for the excellent pictures, it will be most helpful for the community. I have seen so many old 34401A with barely visible displays out there, those owners can really benefit from it. Do you happen to have one of it powered up as well?Thanks for sharing.Quote from: coromonadalix on March 21, 2019, 05:12:33 pm

author: artag
author_rank: Super Contributor
timestamp: March 22, 2019, 07:50:17 pm
content: Are there any other common VFDs available ? I'd love to get hold of a Keithley 2000 and an HP53131A VFD

author: 4thDoctorWhoFan
author_rank: Regular Contributor
timestamp: March 22, 2019, 08:00:41 pm
content: Quote from: artag on March 22, 2019, 07:50:17 pmIt would also be great to get some replacement VFD's for the Fluke 8840A & 8842A displays.

author: coromonadalix
author_rank: Super Contributor
timestamp: March 22, 2019, 08:19:25 pm
content: for the powered one photos i'll post them in 1-2 days i'm not at home until the weekendI have my old original hp Agilent vfd at 50% of brightness left, if someone want it, ill give it free just pay the shipping

author: coromonadalix
author_rank: Super Contributor
timestamp: March 23, 2019, 05:32:08 pm
content: here ya go, room slightly darkThe windows bezel need to be polished, but ill loose the company markings ??

author: NoisyBoy
author_rank: Frequent Contributor
timestamp: March 23, 2019, 10:43:46 pm
content: Hey thanks, looks good, all segments are evenly lit, much better than some replacement VFD pictures I saw before.The brand is the same as some of the eBay seller I saw before, but the price is definitely better.Enjoy your meter, thanks for sharing.Quote from: coromonadalix on March 23, 2019, 05:32:08 pm