Use of FC-1 Choke - help

[SteveBrown]

Based on some discussion around October in the SET Assylum I bought a pair of the FC-1 chokes. I have a schematic for use, but none of the choke terminals are labeled on the schematic, the tabs on the chokes are numbered. Can anyone give me some guidance on how to hook this up properly to use as a common mode choke in a choke input filiment supply? I'm going to try it in an 801A preamp project (7.5v, 1.25a). Thanks!

 

[Len]

There are some hookup directions on the product page

http://www.bottlehead.com/store.php?crn=221&rn=436&action=show_detail

I don't know if that helps.

 

[SteveBrown]

Thanks, Len! I must have missed it because it was down at the bottom of the page.

 

[Len]

No problem.

Can you post a schematic of how you plan to use it in the preamp?

Just interested. I'm using putting some Hammonds, without rectification before them, into my 45 amps, and some more of them after rectification into the DHT elements of my phono pre. I'm very interested in the FC-1's, but money is tight and I have half a dozen 2A .7 DCR Hammonds left over from other projects and I figured I'd try them first.

 

[SteveBrown]

Was planning on choke input, and if not enough output voltage, boosting it with an input cap. However, I've been listening to one channel of my 801a preamp and I have to say it is VERY microphonic. Not sure this is a good path to be on. I have two Herbie tube dampers on one tube and it is still picking up junk. Now I'm thinking a preamp based on a 45... hmm... love the bright fils of the 801, though.

 

[Len]

Phil Sieg built a unity gain line stage with a 45, IIRC. I don't know if there are schematics around.