[AMPS] B&W 852 Coil

[Jon Ogden]

>The B&W homepage lists the B&W 850 as still available. This tank coil is
>designed with the taps set for an inductance that yields a characteristic
>impedance suitable for the 4-1000A operating at max plate voltage

NO! NO! NO! NO!  The B&W 850 was NOT designed for the 4-1000A.  It's 
inductance values are not even close and you have to do some real 
fiddling to make it work with proper Qs.  The impedance of a 4-1000A at 
6KV is around 5KOhms.  The 850 was not designed for that.  Trust me.  I 
just finished my 4-1K amp around that tank coil.  It was a pain.

That coil was designed to be used with samller tubes with much lower 
output impedance.  For example, the 10M coil is less than 0.8 uH.  Using 
that with a 4-1000A at 6KV will result in your loaded Q being around 40!  

73,

Jon
KE9NA


--------------------------------------------------------------------------
Jon Ogden

jono@enteract.com
www.qsl.net/ke9na

"A life lived in fear is a life half lived."


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