Unknown tube in Rohde & Schwarz HS86 Netzgerät

ID: 287423
This article refers to the component: To the tube/semiconductor

? Unknown tube in Rohde & Schwarz HS86 Netzgerät 
11.May.12 14:13
129

Allan So (HK)
Articles: 15
Count of Thanks: 7

Dear Senior members,

I have a Rohde & Schwarz HS86 mains voltage stabilizer, it has one EL34 and a diode called D1.8/1.2

It looks like a high voltage diode (hochspannung diode) made by Heimann. I need to buy one or two as backup, but I could not find any from tube sellers worldwide (ebay), please advise where I could buy this diode.

Danke!

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 2
not a high voltage diode 
12.May.12 20:35
129 from 4343

Wolfgang Holtmann (NL)
Editor
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Wolfgang Holtmann

Hallo Allan

Concerning the D1,8/1,2:

May I draw your attention to the excellent article over a tube with nearly the same function, the 2AS15.

Kind regards.

P.S.

On second thought, the Heimann D1,8/1,2 may be originally utilized as a high voltage diode in other applications?

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 3
Thank you so much! 
13.May.12 05:15
167 from 4343

Allan So (HK)
Articles: 15
Count of Thanks: 6

Dear Mr. Holtmann,

The article is really useful, and the circuit ressembles the R&S HS86 a bit(the "saturable reactor" looks like the choke with 3 coil partitions) I don't know if this circuit has anything to do with a Ferroresonant Transformer for voltage regulation. Meanwhile a friend of mine will sell me one of his D1.8/1.2 tubes, at least I have two on hand for one or two decades (I guess these tubes have long lives). I measure the voltage inside the R&S HS86, the plate cap carries 25VDC only, AC ripple is minimal, no sharp spikes etc. Current should not be high since R&S uses thin wire to connect the tube (I have not measured its current).

Anyway, I will search for 2AS15 and stock some as backup.

Thank you so much Mr. Holtmann! Keep in touch!

Kindest regards

Allan

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 4
D1,8/1,2 
30.Jan.16 23:53
1982 from 4343

Rolf Rudi (N)
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Rolf Rudi

 5
New model proposal 
31.Jan.16 01:22
1989 from 4343

Bernhard Nagel (D)
Officer
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Bernhard Nagel

Dear Allan,

please introduce the Rohde & Schwarz HS86 power supply as a new model for RMorg.

In 2012, you've started an earlier forum article for this AC power supply where Michael Watterson asked the same.

Thank you and kind regards,
Bernhard

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