Advice HP E3610 vs HP 6236B - Page 1
Forum section: electronics / general

author: bingo600
author_rank: Super Contributor
timestamp: May 29, 2012, 04:59:28 pm
content: Gents i need some adviceI have bought a HP E3610A on ebay , 17-May.Condition was : Seller refurbished - fully workingPrice €100 + €30 in shipping.As i still havent received it , i asked seller for a tracking number.But got this ansver (why should that take 10+ days anyway ? ):QuoteI'm wondering what i should do .....I have 2 HP 6632B's (nice but noisy), and bought this one for fanless burn-in of misc Rubidiums , Voltage-Ref's etc.So i was really hoping for a E3610A.I'm a bit of an analog noob , but doesn't have a "dual output PSU".Maybe later on in my electronic quest i'll play around with opamps ,where +/- 20v is nice.My question is if €100 is a good price for a 6236B , and i should say yes for the "dual function" , or if i should let the deal go back. And hope for another "Payable E36xx PSU - in EU"And maybe even complain to ebay (they prob doesn't care anyway)TIABingo

author: free_electron
author_rank: Super Contributor
timestamp: May 29, 2012, 05:29:52 pm
content: Ah the old bait and switch routine heh...The 6236B is not bad but is a generation older than the e3610.The e3610 has digital meters as opposed to analog on the 6236B .E3610 is fixed voltage , so if you are in europe : do NOT buy a US version ! can't switch it (needs new transformer ) !6236B is switchableproblem with the 6236B is that it uses chips in to99 ( round metal can ) which are made out of unobtainium...that supply is obsolete..the E3610 is still in production !the E3610 are easy to repair. there's 3 opamps in it. LF411 , LF359 and aLM393 if my memory works well. there is exaclty 2 transsitors and a pair of lmm317 lm337 for opamp supply.repairing is easy. 5$ in parts will brute force replace all chips and transistors. full schematics can and service manual can be downloade dfrom agilents website for free.http://cp.literature.agilent.com/litweb/pdf/5950-1782.pdfgives you the 6263bhttp://cp.literature.agilent.com/litweb/pdf/E3620-90001.pdfgives you the e3610 family ( there's more then one. only difference is voltage rating on the caps / transformer and end stage transsitor + some passives change. schematic is identicali would go for the e3610. bid it down 20$ and repair it yourself. they are very easy to service. pop the rear bezel off , open clamshell . done. not a single screw. all through hole parts easily accessible. the service manual even has a fault isolation flowchart telling you what is bad in what condition. and the front panel pots are multiturn ...

author: T4P
author_rank: Super Contributor
timestamp: May 29, 2012, 05:50:53 pm
content: When it comes to buying things my main priority is to NOT buy something made out of unobtainium or anything older then the E3000 seriesBecause the parts have all gone obsoletium, i would rather not touch a power supply like that ... or a analog meter power supply

author: bingo600
author_rank: Super Contributor
timestamp: May 29, 2012, 06:16:19 pm
content: Thanx guyzzI have contacted the seller , and told him that i would like to try to repair it.I also wrote that a 25% decuction in price would be fair , for a defective PSU.I will let you know the outcomeBingo

author: bingo600
author_rank: Super Contributor
timestamp: June 03, 2012, 03:44:14 pm
content: Well the PSU should be on the way here.Seller accepted a 25€ deduction from 100 to 75€ , as the PSU is defective.So now i'm just waiting and hoping i can fix it.Well i hope to get some help from here if i get stuck.Thanx guyzz/Bingo

author: drakke
author_rank: Regular Contributor
timestamp: March 03, 2015, 01:58:19 pm
content: Quote from: free_electron on May 29, 2012, 05:29:52 pmCan you tell me how you found these HP/Agilent manuals?Maybe it is not possible anymore. I cannot seem to replicate this search.

author: rdl
author_rank: Super Contributor
timestamp: March 03, 2015, 09:54:37 pm
content: I have a couple of the E3610A, neither really works right. I downloaded a manual for it and a bunch of "service notes". Nothing I have has any kind of "fault isolation flowchart" that I remember. I'd like to find that. None of the "service notes" I found specifically address the problem my E3610As have, but I can post them here if you can't find them.

author: drakke
author_rank: Regular Contributor
timestamp: March 04, 2015, 06:44:30 am
content: Quote from: rdl on March 03, 2015, 09:54:37 pmThat's ok. I have some manuals.I wanted to know how to search Agilent's literature repository.

author: macboy
author_rank: Super Contributor
timestamp: March 04, 2015, 05:39:32 pm
content: Quote from: free_electron on May 29, 2012, 05:29:52 pmYou linked to the E3620A manual. This is quite different than the E3610A. It doesn't overshoot when you turn it on, and doesn't oscillate with certain loads, for example. The E3620A uses a single darlington BJT as a series pass transistor; the E3610A and siblings use MOSFETs. Also, the manual you linked to does not have the schematic (that was removed after Agilent stopped servicing these at the component level).The E3610A/E3611A/E3612A share a common design and schematic (with small variations). This must be what you were thinking.You might tryhttp://www.physics.fsu.edu/users/Wahl/labmanuals/instruments/ps/AgilentE361xAManual.pdf

author: rdl
author_rank: Super Contributor
timestamp: March 05, 2015, 12:13:28 am
content: Quote from: macboy on March 04, 2015, 05:39:32 pmWait a minute, overshoot and oscillate? You are saying that this is how the E3610A worksnormally?

author: macboy
author_rank: Super Contributor
timestamp: March 05, 2015, 12:39:04 am
content: Quote from: rdl on March 05, 2015, 12:13:28 amSadly yes. This is not HP's finest design. There are service notes on the Keysight site that detail some of these problems and modifications to fix them. Look up the model number, go to document library, and find service notes.

author: rdl
author_rank: Super Contributor
timestamp: March 05, 2015, 12:50:06 am
content: I have all the service notes. None of them specifically mentions overshoot when turned on. I think one said something like "overshoot when voltage pot is adjusted", and there are a couple that do mention oscillation.