HI Justin
you can also open the switch with a 9V battery.
Clemens
On 5/20/2026 5:30 PM, Jeff Walton via groups.io wrote:
Hi Justin,
It really is just two large crossed diodes. Large in that they can handle the
current that the magnet will put through it and crossed because you either
don’t know the direction of the current or you might make a a mistake
as to the direction. Also the diodes are usually mounted on a large aluminum
heat sink with fins to dissipate the heat. For a 600 you might want a fan….
Good Luck!
Jeff
On May 20, 2026, at 10:48 AM, Justin Pontius via groups.io wrote:
Hi,
We're planning on decommissioning our Varian 600 DDR system. It has an
unshielded Oxford round bottom magnet and I have the charging rods. We
were planning on pulling the vacuum and just letting it quench, however
it would be nice to bring it down gently if possible.
Back when I worked for JEOL some 15-16 years ago we had a diode box and small
power supply to open the main switch. Before I do anything stupid, does
anybody have details or schematics for such a diode box? I seem to remem ber
it was just 2 very large opposing diodes and maybe a fan. large resistor?
Any insights?
--
==========================
==========================
====================
Clemens Anklin Ph.D. Vice President
Bruker BioSpin NMR Applications & Training
15 Fortune Drive NEW Phone: 978-313-5NMR(5667)
Billerica MA 01821 bluesky: _at_canklin.bsky.social
web: http://www.bruker.com
e-mail: clemens.anklin_at_bruker.com
==========================
==========================
====================
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#3479): https://urldefense.com/v3/__https://ammrl.groups=
.io/g/main/message/3479__;!!PvDODwlR4mBZyAb0!UW4zaFLL5jw42mL4KOFVrCI2h3OF_V=
lIb6oRTt1tcS7tSLUAyznloJim3bCcS_FbOumWfynlXYsJVFPURhhoJ6-MNGCf$
Mute This Topic: https://urldefense.com/v3/__https://groups.io/mt/119414580=
/7559972__;!!PvDODwlR4mBZyAb0!UW4zaFLL5jw42mL4KOFVrCI2h3OF_VlIb6oRTt1tcS7tS=
LUAyznloJim3bCcS_FbOumWfynlXYsJVFPURhhoJ_2i4Iwv$
Group Owner: main+owner_at_ammrl.groups.io
-=-=-=-=-=-=-=-=-=-=-=-
Received on Wed May 20 2026 - 21:12:08 MST