Re: New Sangean DT-400W


Michael <michael.setaazul@...>
 

Thanks for the update, Paul. I look forward to reading how it looks and performs.

Michael UK
----------------------------------------------------------------------------------------------------
---------
Apropos : Things seem to have gone quiet on the ferrite front.
Any new or improved designs in process?

Michael UK

----------------------------------------------------------------------------------------------------
---------
Indeed, have the flat ferrites now (100mm*3mm*20mm) but looking for a large
diameter plastic tube dia => 12" to about 20".
This follows directly from Steve's assertion that a large diameter is needed
following his experimental evidence posted in this group.

Will place ferrites on each end and wind the contra-winding as per the
Polydorroff patents and will be the ~ 1/4" off ferrite surface.
This is the kind of plastic form I am
consideringhttp://www.usplastic.com/catalog/item.aspx?itemid=23849&catid=459

a grounded cage variable capacitor will be used to resonant.
pickup will be via a ~ 24" ferrite rod ( 3 * 8"by 1/2" dia 61 material Amidon0
this will have a contra-winding upon its surface (distance of wire to ferrite
surface ~ 1/4")
The idea is that placing this rod in the centre the mutual coupling will be such
that it is weak and therefore will not upset the Q of the main tuning circuit
yet enough signal for a sensitive radio.

all I have for now Michael
best wishes
Paul in the Northern Colony
VE3PVB

Join main@UltralightDX.groups.io to automatically receive all group messages.