HP (Harrison) 6209B HV supply (320V at 0.1A) - Page 1
Forum section: electronics / testgear

author: anotherlin
author_rank: Frequent Contributor
timestamp: August 23, 2013, 03:41:36 pm
content: Just scored this one on ebay.It is a Harrison/Hewlett Packard branded 6209B high voltage power supply, 320V at 100mA.It's a 110V model but primaries can be rewired for 220V operation.This is well explained in the operating/service manual (http://cp.literature.agilent.com/litweb/pdf/06209-90003.pdf).I'll do that later but as I have a 220V-110V transformer, I was able to do a quick test. It works!I couldn't resist but open it. All components seem original, especially the caps. And they all seem to work fine.Here are the photos :<< There used to be links to photos on imageshack, but they are gone, so I edited this post to remove the links. Sorry >>

author: anachrocomputer
author_rank: Regular Contributor
timestamp: January 20, 2015, 01:51:12 pm
content: When I click on those photos, I get an annoying advert that I cannot skip (or even silence), then another unrelated video clip. Do you have the photos uploaded anywhere else?

author: anotherlin
author_rank: Frequent Contributor
timestamp: January 20, 2015, 01:54:13 pm
content: I reposted some of them in the "current" thread.I will edit the "previous" post to remove the links to imageshack. Sorry for the inconvenience

author: AMR Labs
author_rank: Frequent Contributor
timestamp: March 27, 2025, 07:27:04 pm
content: Very old thread but hoping someone might have the HP6209B user/service manual that includes the PCB and component layout? I've got the one that seems to be everywhere, PN 06209-90003 from June 1969, and it has the schematic but no board or component views. It is also meant for serial numbers starting with 7F1117 and above. Mine is SN 7F10xx so slightly bellow that breakpoint.Mine seems to be working fine, output voltage range checks out, and voltmeter scales are reading fine now after calibration (they where about 5V high).Only issues are some rather unusually stiff and somewhat hard to turn (but working) current 10-turn pot, and also when I switch the meter to 12mA range the needle pegs all the way to the left beyond zero, even without any load connected. The 120mA range seems ok other than it was reading a bit low, but calibration solved that. If I put a 10mA load and select the 12mA range it reads around 8mA, even after the previous calibration of the 120mA range, and pegs again to the left after a second or so once the load is removed. Guessing an out of tolerance resistor in the current meter circuit, but it would be easier and more convenient to track it down if I had the parts location on the main board as some parts label designations are obscured by the part itself. Otherwise guess I'll just map out all the board components.TIA.

author: AMR Labs
author_rank: Frequent Contributor
timestamp: April 01, 2025, 06:10:12 pm
content: Turns out C12 was bad. Its a 450uF 85V cap in the bias supply, and it measured 135nF.The +43V supply was only showing 34.2V, but when I set the DMM to AC there where 14VAC of ripple across the cap.After replacing that cap with a 470uF 100V the voltage rail came up to +43.4V and the meter on 12mA scale no longer was pegging to the left, but now rather showing 4mA with no load. Had to adjust R38 and that brought it down to zero without affecting the general zero adjustment of the meter. Then went through the meter calibration routines for both voltage and current and all is good now.The other big caps, C14 and C20 both tested good so left them alone. Ripple at the output set to 320V with a 100mA load is about 1mV.