Re: [TenTec] Orion freezes due to RFI??

[Henry Gardiner <hgard1@airmail.net>]

Rick,
    Here is what I used to bypass the speaker output jack on my RX-350D 
aka JUPITER rcvr.
   0.1 uF disc capacitors go to ground from each of the three pins on the 
jack that have traces going to them.  Also a three-winding common-mode 
blocking transformer.  I used three lengths of 22 ga magnet wire twisted 
together at a convenient rate.  This was wound through the FT50-72 core 5 
times. This was interposed in the circuit between the jack pins and the 
nearby pcb connectors using a Dremel tool with fiberglass cutting disk to 
cut the three traces.  AAACK!!!  Use the same winding polarity in each 
case.  Ie, if the counterclockwise end of a winding goes to a speaker jack 
pin, so should the counterclockwise end of the other windings go to their 
respective speaker jack pins.
    Might try this first with just the three 0.1 uF disc caps plus your 
external clamp-on ferrite choke. That might eliminate the need for the 
transformer and the cut traces.  Or you may end up using the transformer, 
caps and clamp-on choke.
    Basic parameters: Each winding is about 100 ohms at 1 mHz.  The caps 
are something like 1.5 ohms at 1 Mhz.  The toroid data is in the ARRL 
Handbook in the chapter "Component Data".
    This schematic expects a mono-spaced font like Courier or Courier 
new.  Might be easier to cut it and paste it into an editor and change the 
font there.
    Perhaps we should let this get reviewed for a while before one of us 
invests the time in drawing the schematic more formally.

73,
Henry AC5LA




            J3
           +--++                                          J5
     To    |  ||2-+                              Rear Panel Spkr Jack
   Speaker |  ||  |
           |  ||1-)--+        +---+-----------------o----------
           +--++  |  | Xformer|   |                     /|\ .
                  |  |  .___  |   |              +--o----|  .
                  |  +---UUU--+   |              |          .     ++
                  |     .___      | +-------+----)--o--------\    ||
                  +------UUU------)-+       |    |            \/  ||
            J4    |     .___      |    +----)----+--o-------------++
           +--++  |  +---UUU------)----+    |
  To       |  ||2-+  |            |    |    |
  HdPhones |  ||     |            |    |    |
  Jack     |  ||1----+           ---  ---  ---
           +--++                 ---  ---  --- 0.1 uF 25V
                                  |    |    |    x 3  disc ceramic
                                  |    |    |   Connect caps to three 
terminals on speaker
                                  |    |    |   jack with traces leading 
to them from pcb
                                  |    |    |   connectors.
                                 ===  ===  ===
                                 GND  GND  GND
                                      GND:
                                      Trace Leading
                                      To Nearby
                                      Mounting Post

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de


_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec