Repairing JBC CD-2BB - Page 1
Forum section: electronics / repair

author: f0ns
author_rank: Newbie
timestamp: December 27, 2023, 05:10:36 pm
content: Hi!I want to repair my JBC-CD-2BB, the problem is the component near the ribbon cable in the main board is destroyed (photo attached) and I don't know what component is.When I plug the soldering station it reports this error: WARNING #13: Mains frequency error. Contact with the technical service.I tried to get some schematic of the circuit but I can't find it.Could you provide some help telling me the name of this component to replace it or providing some schematic/gerber?Best regards

author: JimKnopf
author_rank: Frequent Contributor
timestamp: December 27, 2023, 08:38:14 pm
content: Maybe you already found this by yourself :https://www.eevblog.com/forum/testgear/jbc-soldering-station-cd-2bc-complete-schematic-analysis/I was able to repair my CD-2SQE with this schematic from the first post. It's a different modell.Dave did a review

author: f0ns
author_rank: Newbie
timestamp: December 27, 2023, 11:31:02 pm
content: Thanks you! I have already seen this post but i couldn't identify the component in the schematicI was watching the Dave review but I couldn't identify it neitherI take this capture from the video. Maybe it could be a fuse?

author: fzabkar
author_rank: Super Contributor
timestamp: December 27, 2023, 11:44:08 pm
content: It appears to be connected across the 23VAC supply, in which case it could be a bidirectional TVS diode.

author: JimKnopf
author_rank: Frequent Contributor
timestamp: December 28, 2023, 05:47:17 am
content: @fzabkar Indeed there was a TVS Diode in my CD 2SQE too. After reading your hint, i remember this Diode was placed on the other side of the wire, the Transformer side. I replaced it because it looked damaged to me. At that time i testet it with only a DMM. Max testvoltage 10 volt (Keithley DMM 6500). Later i found out the Diode was in working condition.So you can't find this Bi-TVS Diode in the Schematic from above because it is undocumented on the transformer side. In my case it was BFP. It looks a bit bigger than the one from Dave's Video. But i also think it is a Bi-TVS Diode. The wire to the transformer is in the middle of the mainboard on the CD 2SQE. Maybe thats the reason they placed it on the other side of the wires because there was no space left for such a big Diode on the mainboard.I replaced it with a SMCJ36CA. I remember the CA at the end stands for bi-directional type.

author: JimKnopf
author_rank: Frequent Contributor
timestamp: December 28, 2023, 10:31:49 am
content: Dave uploaded some images of his review to flickrhttps://www.flickr.com/photos/eevblog/8872687151/in/album-72157633774612230/Maybe he can provide an image in proper quality.Or ask Chatgpt if he can make a bom list from this image

author: eb4fbz
author_rank: Regular Contributor
timestamp: December 28, 2023, 03:04:14 pm
content: Similar JBC stations have a CBN marked TVS diode there. That means SMBJ36CA

author: JimKnopf
author_rank: Frequent Contributor
timestamp: December 28, 2023, 03:18:54 pm
content: The one from this topichttps://www.eevblog.com/forum/testgear/240v-120vmagic-smoke-jbc-edition/is a STM CBN (JBC CD-1BB).

author: fzabkar
author_rank: Super Contributor
timestamp: December 28, 2023, 05:33:19 pm
content: 23V (RMS) x sqrt(2) = 32.5 V (peak)Therefore, a standoff voltage of 36V makes sense.I would be inclined to modify the design by inserting a fuse in the 23VAC supply.

author: f0ns
author_rank: Newbie
timestamp: December 29, 2023, 10:24:07 am
content: Thank you very much for the answersI'm goint to ask for the SMCJ36CA in Mouser.I also want to get a replace for the ribbon cable, do you guys know which model fits well?