Keithley 2200 Display - Page 1
Forum section: electronics / repair

author: inse
author_rank: Super Contributor
timestamp: July 07, 2025, 07:27:35 pm
content: I came across a Keithley 2200 power supply, single channel version.Unfortunately the front panel has been abused and the VFD is smashed.Above that it appears to work as I blindly entered some voltage values and the output reacted accordingly.The VFD is a Futaba 242-SD-04GNM 24x2 dot matrix without special indicators.So far my research was dead-end, has anyone an idea where to get replacement at a reasonable price?I wouldn’t mind botching in a different display.

author: coromonadalix
author_rank: Super Contributor
timestamp: July 08, 2025, 10:37:11 am
content: here ?and some specshttp://www.electronic1688.com/shop/goods/product/813/95.html

author: inse
author_rank: Super Contributor
timestamp: July 08, 2025, 11:18:34 am
content: Great find, thanks a lot.I hope this is a reputable shop…

author: inse
author_rank: Super Contributor
timestamp: July 09, 2025, 07:41:18 am
content: “we have checked warehouse,this model have no in stock“🙁 I‘ll keep searching…

author: coromonadalix
author_rank: Super Contributor
timestamp: July 09, 2025, 09:12:19 am
content: https://www.alibaba.com/product-detail/24x2-Character-VFD-Display-Screen-M242SD04AJ_60703379177.htmlnot sure if this one can subs't itor this ?https://www.surenoo.com/products/6681632https://www.matrixorbital.com/mop-al242aor like theses on Ebay, but you ned to know the working modes if they have themhttps://www.ebay.com/itm/116605692947?because your's have 3 interface modes, or called "6800-series parallel interface" and "8080-series parallel interface" for sure it is not 44780 mcu based ...maybe search with the mcu id's or specs on your vfd, you can or may find ones that are not vfd but lcd insteadand others may have some small dc-dc converter on them for negative voltage etc ... a matter of knowing the interfacing type and finding the one who could fit ?

author: inse
author_rank: Super Contributor
timestamp: July 09, 2025, 12:30:43 pm
content: Thanks for the reply, coromonadalix.See the damage in the photo, the driver is on the front panel PCB, so finding a replacement VFD glass is my first choice.I also checked the controller datasheet, it is controlled via SPI.An entire display module with another sufficently compatible controller also came to my mind but might run into clearance issues.Currently I am onto a Hungarian shop that sells a module with the right VFD glass which I plan to salvage.It’s the same you tracked down at alibaba.

author: coromonadalix
author_rank: Super Contributor
timestamp: July 09, 2025, 01:34:26 pm
content: ohhhhhhhhhhhhhh damn it's really the glass no controller, ooops that's another ball game ...the frame took some hits tooonly solution is finding a part donor for the vfd glass, who seems unobtanium ? not sure if the 2231 has the same ?good luck and sorry if it was kinda misleading

author: inse
author_rank: Super Contributor
timestamp: July 09, 2025, 01:43:14 pm
content: The set looks (looked) like it had been used as a ice hockey puck.The seller had been discussed here already regarding a smashed oscilloscope.He has several abused T/M gear in his portfolio, everyone wonders about the origins

author: coromonadalix
author_rank: Super Contributor
timestamp: July 09, 2025, 01:45:39 pm
content: well if its the casehe tries and sell damaged goods for sure, but theses seems to be "eliminated" and purposely damaged against any reselling "good stuff" attemptsyou buy at your own risksthe vfd hole in the center look like an hammer impact ?and the possibility is there, that even with a new vfd, other damage are there ... the cheapest 2231 models start at 450$ usd, the 2200 for more

author: inse
author_rank: Super Contributor
timestamp: July 09, 2025, 02:27:17 pm
content: Without display, I simply entered voltage and current values via the keypad with multimeter attached and they were spot on.So far I only seem to need a new VFD (challenging), three binding posts (in stock), tinted plexiglass (easy) and a knob for the encoder (in stock).Unfortunately the price structure for second hand T/M gear in Germany cannot be compared to the USA, to say the least…

author: inse
author_rank: Super Contributor
timestamp: July 25, 2025, 06:50:24 am
content: Update to the repair process: success!I bought an entire VFD module from a vendor in Hungaria and desoldered the glass to fix the front panel.Then I cut some acrylic to replace the screen window and put tint film as contrast filter on it.The result is almost satisfying as some tiny bubbles got trapped.Found a nice replacement knob for the encoder and fitted new binding posts.The unit works perfectly, the output can be set in mV and uA resolution.

author: the Chris
author_rank: Regular Contributor
timestamp: July 25, 2025, 07:16:04 am
content: That's a very fine result considering the starting point of your repair. Well done!