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Old 5th January 2013, 08:46 AM   #1341
vgeorge is offline vgeorge  Greece
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The chokes are LL1667 25mA.
Yes Massimo, it is what I had in my drawer!
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Old 5th January 2013, 09:41 AM   #1342
stajo is offline stajo  Sweden
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I have a bunch of old Hinchley chokes, weigh just over the kilo and measuring 115 H and around 950 ohms. I have no data except that but I think they would be up to the task of inductively loading 6V6 in this config very well, even with more current.

Staffan
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Old 5th January 2013, 09:50 AM   #1343
massimo is offline massimo  Italy
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The chokes are LL1667 25mA.
Yes Massimo, it is what I had in my drawer!

Those are OK with #26

Happy New Year George!
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Old 5th January 2013, 09:52 AM   #1344
vgeorge is offline vgeorge  Greece
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Those are OK with #26
I had those on my #26 pre, before switching to transformer output with ll1660.
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Old 5th January 2013, 09:53 AM   #1345
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Plot is to set SSHV2 to 20 mA current limit and upping the bias a bit? What LL chokes are that?

My breadboard is on the kitchen table again. Prepping for 1660.

Staffan
I mind LL is the abreviation of Lundhal transformers.
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Old 5th January 2013, 09:57 AM   #1346
stajo is offline stajo  Sweden
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I mind LL is the abreviation of Lundhal transformers.
Spot on Mr Magician
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Old 5th January 2013, 10:20 AM   #1347
massimo is offline massimo  Italy
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I had those on my #26 pre, before switching to transformer output with ll1660.
No doubt!
Let us know how LC load performs vs RC. I'm quite confident it will be better sounding.
I'm very intertested as I have a pair of Iso-Tango anode choke (TC-60-35W) 60H/35mA unused in my drawer that should fill the bill. With a Rdc of 730 ohms what I have to do to try them is to lower the supply voltage to 245-250 to get the same 230-235 V on anode as per the lastest sch.
Unless Salas will recommend some other mods.....

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Old 5th January 2013, 10:45 AM   #1348
Salas is offline Salas  Greece
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It takes >=50K amp to do this FFT. The resistive one holds spec (worse) down to 20K, and the buffer down to 5K. Good luck when making it.
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Old 5th January 2013, 10:49 AM   #1349
Salas is offline Salas  Greece
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Unless Salas will recommend some other mods.....
Just hold the same bias point, i.e. circa 235V on the plate and 15V on the cathode. The more the inductance the less the THD at more the swing, goes without saying.
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Old 5th January 2013, 10:53 AM   #1350
Salas is offline Salas  Greece
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Quote:
Originally Posted by stajo View Post
Plot is to set SSHV2 to 20 mA current limit and upping the bias a bit?
Staffan
20mA is the preamp's bias current, CCS should be 40mA when using double SSHV2, or 60mA when using common.
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