HP 6113A Voltage Reference - Page 1
Forum section: electronics / testgear

author: gilbenl
author_rank: Regular Contributor
timestamp: December 04, 2014, 10:55:41 pm
content: Hello all! New member here, but a long time lurker with an interest in metrology. Great forum y'all have here!Recently, I picked up a like-new HP/Harrison 6113A DC reference for $35! Still had a HP seal on one of the casing screws dated 12/62. Cool piece of history and very satisfying to tear off after 62 years. Did a calibration and its been rock solid for the last 24hrs. However, it took every bit of a 4-6 hours for the thing to calm down (this was pre-calibration). I suspected an issue with the feedback circuit, but it all checked out and its been steady since.At the end of Dave's video on the Krohn-Hite DC reference, the gentleman at TrioSmartCal quips "Now take it home and never turn it off." I used to do research in protein separation and I kept my HPLC machine running 24/7(sometimes months on end). That's par for the course. I know someone who's had theirs running almost non-stop for 3 years now.I expect to use the unit a couple times a month. Is there any benefit to keeping it powered on at all times as opposed to turning it on a day before use? Better question-Is there any reason not to keep it on? At 62 (albeit easy years), I don't want the darn thing burning my house down.

author: SharpEars
author_rank: Unknown
timestamp: December 05, 2014, 01:51:58 am
content: Personally, I'd go for Data Precision for this sort of mental masturbatory equipment. Now if you were shooting for high power at high voltage, HP wins hands down. HP has some great vintage supplies, but 10 volts at 2 amps, well it just sounds impotent to me.

author: johansen
author_rank: Super Contributor
timestamp: December 05, 2014, 01:53:22 am
content: the folks over at the volt-nuts mailing list would know more than anyone here.

author: SharpEars
author_rank: Unknown
timestamp: December 05, 2014, 01:57:22 am
content: The 6115A looks interesting, though.

author: SharpEars
author_rank: Unknown
timestamp: December 05, 2014, 01:59:30 am
content: Quote from: johansen on December 05, 2014, 01:53:22 amI highly doubt that, since we collectively own all of the "choice" equipment. Most of the threads there are on amateurish equipment, with the 3458A thread being the only exception I saw.

author: Vgkid
author_rank: Super Contributor
timestamp: December 05, 2014, 02:28:32 am
content: It is just running an ovenized 1n825, no reason to keep it continously powered on.

author: robrenz
author_rank: Super Contributor
timestamp: December 05, 2014, 02:39:59 am
content: Quote from: SharpEars on December 05, 2014, 01:57:22 amThe 6114A and 6115A are awesome power supplies. The specs are hard to beat even with modern supplies.my restoration of a 6114Ahere

author: gilbenl
author_rank: Regular Contributor
timestamp: December 05, 2014, 04:19:57 am
content: Quote from: robrenz on December 05, 2014, 02:39:59 amThanks for the replies and nice refurb! I assume the performance improved as a result? Years of sitting without use has put some corrosion on the decades, and given the simplicity of the 6113 compared to the 6114, it might be something worth undertaking. As far as the value of these things, it's specs put my E3610 to shame (see spec side-by-side below). For my purposes, 10V 2A is gobs o' power. I don't think I've ever taken the 3610 out of the 2A range.The only answer I see to my original question was a vote for turning the thing off. Guess I could do some experimentation to see if theres any difference.

author: TSL
author_rank: Regular Contributor
timestamp: December 05, 2014, 05:35:44 am
content: You could also supplement it by using a battery powered transfer standard such as those found here...http://www.voltagestandard.com/I've no relation to the seller other than being a happy customer.regardsTim

author: saturation
author_rank: Super Contributor
timestamp: December 05, 2014, 01:05:34 pm
content: The 6113a is a precision power supply; the 6114a, 6115a etc., were its successor models. Its more like the Power Designs precision supplies in that they have very stable output but only have current limiting protection by shut off rather than switchover to CC mode, when at the limit.You can turn it off.What you experienced on turn on could be due to many things and is a very long story related to aging of electronic components, but the most critical is from any old electrolytic caps reforming, if the unit hadn't been turned on for many years. Since it survived it, then the electrolytics are reformed to like new. I normally leave old gear that has been in storage to unknown times on for 1 week before putting it into service and thereafter, just doing it several times a year will suffice which is moot if the device is on duty frequently. During that week, monitor the interiors for impending failures or unusual build up of heat, a good IR thermometer or your finger will work. Without a load and quiescent, nothing should be too hot to touch unless it says so in the schematic [e.g. an oven].Of many phenomena thermal shock is a key killer of components particularly if loaded before it can settle.A voltage source with an adjustable output is not a voltage reference or standard; adjustments to a reference are for calibration against a standard and are typically not easy to get too, and a standard is most often, never adjusted. Both a reference and standard are best never turned off once settled.Enjoy.Quote from: gilbenl on December 05, 2014, 04:19:57 am

author: SharpEars
author_rank: Unknown
timestamp: December 05, 2014, 05:46:37 pm
content: Quote from: robrenz on December 05, 2014, 02:39:59 amRob, you are the restoration master!

author: robrenz
author_rank: Super Contributor
timestamp: December 05, 2014, 06:53:46 pm
content: Thanks, its a labor of love.If you liked that you may want to look atthis oneorthis one

author: VK5RC
author_rank: Unknown
timestamp: December 06, 2014, 07:05:27 am
content: Thanks for sharing your 'secrets', again fantastic results. I missed the original post.