Printing text on front panel - Page 1
Forum section: electronics / general

author: TimNJ
author_rank: Super Contributor
timestamp: May 07, 2013, 10:16:05 pm
content: I bought an old HP power supply off eBay for $30 shipped. It's a model 6214A. 0-12V, 0-1.2A. I think it's from ~1970.I am anticipating that it will actually need a new enclosure because the one it was given 40 years ago is notorious for becoming brittle and falling apart.Perhaps this won't be true, but if I did get a new case for it, I would need some way of labeling the controls. Is there any feasible home method that will allow me to get the text printed directly on the front panel. I can of course use a big sticker, or perhaps a big sheet of sticky matte laminate with text printed on it. Is that the most feasible option?Thanks.

author: free_electron
author_rank: Super Contributor
timestamp: May 07, 2013, 10:26:59 pm
content: self adhesive laser transparencies or vinyl sheets. work like a charm

author: lemmegraphdat
author_rank: Frequent Contributor
timestamp: May 07, 2013, 11:06:16 pm
content: Take a picture of the front panel for future reference and maybe just use a sharpie on the new box?

author: TimNJ
author_rank: Super Contributor
timestamp: May 07, 2013, 11:19:22 pm
content: Thanks! I was thinking they'd work. How do they "print" on front panels during production? They obviously don't use transparencies.

author: robrenz
author_rank: Super Contributor
timestamp: May 08, 2013, 12:22:54 am
content: Hereis an example of one I did for my micro ohm meter. Be patient, it gets to the making of the new faceplate graphic.

author: CanadianAvenger
author_rank: Regular Contributor
timestamp: May 08, 2013, 01:47:06 am
content: Quote from: TimNJ on May 07, 2013, 11:19:22 pmProduction panels are typically reverse printed adhesive films , silk screened or pad printed. Of the three Silk screening is the most DIY friendly method.

author: amspire
author_rank: Super Contributor
timestamp: May 08, 2013, 01:47:45 am
content: The idea of replacing the case of the 6214A seems nuts - it is a pretty good case.I have a 6213A that was smashed when someone dropped it - that's how I got it cheap.Just repair it. You can't even see my repairs they are so good.There are lots of ways for doing labels, but I am a big fan of Brother PTouch labels for a one off job. The labels never fade, the printing is covered with a tough transparent layer and so it never wears. You can get labels with a transparent backing. If you get a PTouch labeller, get one that acts as a USB PC printer so you can do any font or graphics, rather then the stand-alone units with the keyboards.Edit: The fact that the 6214A has a current control know instead of a fine voltage control knob means I can probably easily convert my 6213A to a 6214A and get the current control. I am sure it is the same PCB inside. I can replace the voltage control pot with a 10 turn pot. I think I will do it.

author: FenderBender
author_rank: Super Contributor
timestamp: May 08, 2013, 02:30:42 am
content: Yeah I have a pTouch it works

author: FenderBender
author_rank: Super Contributor
timestamp: May 08, 2013, 02:32:25 am
content: Yeah probably just some resistor values tweaked and a different transformer. Go for it!

author: amspire
author_rank: Super Contributor
timestamp: May 08, 2013, 02:34:40 am
content: I think it will clean up fine. It is a really nice little supply. Definitely a great buy at $30.

author: TimNJ
author_rank: Super Contributor
timestamp: May 08, 2013, 02:35:42 am
content: Just realized I posted under FenderBender. I made a new account for uniformity's sake. This what my new internet usernames are.But yeah same person. Just different name.Here's the eBay picture. It looks like it might have some rust on it. But for $30, who cares.

author: codeboy2k
author_rank: Super Contributor
timestamp: May 08, 2013, 02:48:34 am
content: Oh man.. the memories.. I had one of PSUs those when I was 12.

author: amspire
author_rank: Super Contributor
timestamp: May 08, 2013, 03:04:29 am
content: Just had a look at the 6214A manual from agilent:http://cp.literature.agilent.com/litweb/pdf/06214-90002.pdfThe quality is terrible. You can hardly read the circuit. The 6213A manual is much better quality.http://cp.literature.agilent.com/litweb/pdf/06213-90001.pdfThe circuits are close enough for the 6213A manual to be useful, but they have made some changes. The current regulation circuit is better in the 6214A then the 6213A.

author: TimNJ
author_rank: Super Contributor
timestamp: May 08, 2013, 05:26:48 pm
content: Quote from: codeboy2k on May 08, 2013, 02:48:34 amWow! Well I'm 18 just for reference. I'm amazed at how well this older stuff holds up. I wonder if today's Agilents will be around in 40 years...hmm...

author: TimNJ
author_rank: Super Contributor
timestamp: May 08, 2013, 05:30:28 pm
content: Quote from: amspire on May 08, 2013, 03:04:29 amThanks. Yeah you'd think the original manufacturer would actually have a decent quality manual!I've yet to see inside one of these. I'll probably be replacing the electrolytics. Probably tantalums too since they are probably wet tantalums.

author: Monkeh
author_rank: Super Contributor
timestamp: May 08, 2013, 05:50:29 pm
content: Quote from: TimNJ on May 08, 2013, 02:35:42 am.. You are aware you can have your name changed?

author: SeanB
author_rank: Super Contributor
timestamp: May 08, 2013, 06:18:17 pm
content: Wet tantalums never die, unless they are the cheap ass ones with a rubber seal, which do dry out with time and go high ESR. I had a lot of fun changing out thousands of those. The glass frit sealed ones last essentially forever, only thing that kills them are reverse voltage, gross overcurrent ( I used one to replace the low ESR cap in a power supply, and it worked well with 10A ripple current, not bad for a 22uF 35V unit) or prolonged overtemp.

author: FenderBender
author_rank: Super Contributor
timestamp: May 08, 2013, 06:27:31 pm
content: I messaged Simon once or twice but I never got a response, so I decided to just make a new one. Maybe I'll message Dave now...I don't really like the idea of having a new account for discontinuity's sake, but I couldn't seem to get into contact with anyone so that's why I did it.And now I'm logged in as FenderBender! What a mess! What have I done!!

author: FenderBender
author_rank: Super Contributor
timestamp: May 08, 2013, 06:28:39 pm
content: Quote from: SeanB on May 08, 2013, 06:18:17 pmGood to know. I thought I remember hearing about old Tek scopes (maybe 70s-80s) that had tantalums that died short circuit.Am I mistaken?

author: SeanB
author_rank: Super Contributor
timestamp: May 08, 2013, 06:42:19 pm
content: Dry ones do have the flaming death syndrome. The cause is often ESD damage which weakens the oxide, and as there is no electrolyte to enable regrowth of the oxide layer, so they eventually degenerate till it breaks down and a large current flows. They do go out with either a whimper if the current is low enough or in a ball of fire and charred board if there is sufficient current. Only mitigation is to use series resistance to limit power into the low impedance failure mode, or use a much higher voltage rating unit than the circuit voltage, like a 5V rail with 25V capacitors on it.

author: FenderBender
author_rank: Super Contributor
timestamp: May 08, 2013, 07:00:20 pm
content: So are the older ones that had problems actually dry types?

author: SeanB
author_rank: Super Contributor
timestamp: May 08, 2013, 07:49:49 pm
content: Yes, the wet ones can regrow the oxide layers if needed, but the dry ones do not have any ability. Any damage and it is ticking off the time till cremation.

author: FenderBender
author_rank: Super Contributor
timestamp: May 08, 2013, 07:59:13 pm
content: Well thanks. I'll take a look at it when I get it.