[ARC5] Info sought about output transformer in BC-221-AK

[J Mcvey]

Just happened upon a passage in the manual that says 'later models used the HS-30 headset". I looked up the HS-30 and it's 256 ohms.Like I said, they were in transition mode mode...
So, the primary should be about 8000 ohm s and the secondary should be 256 (300?) ohms.If you find the turns ratio, it should fit this profile.
 

    On Friday, January 5, 2018 9:17 AM, J Mcvey via ARC5 <arc5 at mailman.qth.net> wrote:
 

 Leslie,
That was a very crytic entry! They will usually at least provide primary and secondary turns...There may be a master "supply list" in that manual with more detail but I don't have time to hunt for it.
None the less, it can be "reverse engineered" by looking uo the 6sj& tube data. At 100V is shows a class A plate resistance of 8250 ohms, so that would be the primary impedance. The secondary is probably called out in the Bc-221AK specs somewhere. Probably somewhere i the 600 to 3000 ohm area. They were in a headphone impedance transition back then, so different versions can require different headphones. If they don't call out the impedance , you may be able to find the spec for the supplied headset.
Hope this helps...
 

    On Friday, January 5, 2018 5:16 AM, Leslie Smith <vk2bcu at operamail.com> wrote:
 

 The subject line is the point of this posting.

More info:  (1) This transformer is shown as item 17 in the circuit diagram for the "AK".
The manual describes this as "output transformer".  
I find no other information in the BC-221 manual.
In particular I wish to know the impedance of the primary & secondary windings.

Thanks to all,

  73 de Les Smith
  vk2bcu at operamail.com
______________________________________________________________
ARC5 mailing list
Home: http://mailman.qth.net/mailman/listinfo/arc5
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:ARC5 at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html


   ______________________________________________________________
ARC5 mailing list
Home: http://mailman.qth.net/mailman/listinfo/arc5
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:ARC5 at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

   
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/arc5/attachments/20180105/0352fe31/attachment-0001.html>