AVS Forum banner

Status
Not open for further replies.
1 - 6 of 6 Posts

·
Registered
Joined
·
26 Posts
Discussion Starter #1
I've just received my Rat Shack double-bow tie antenna here in Metrowest Boston, just in time for the Super Bowl .:cool: Problem is, the 300-ohm lead is not long enough for my set-up. I remember seeing, or hearing about, a modification to replace the twin-lead with shielded cable, to improve reception... involving a bit of soldering.


Does anyone have a link to this information, or can someone give me a quick description of what's required? Thanks in advance.
 

·
Registered
Joined
·
461 Posts
Just snip the twin lead as close to the antenna as possible and wrap each lead around one arm of a 300->75 ohm adaptor. Ask at radio shack if you don't know what one of those is, its 3$.
 

·
Registered
Joined
·
26 Posts
Discussion Starter #3
When you say "300-75 ohm adaptor", are you talking about the twin-lead transformer type, or the box-like converters with the double screw-down posts?


I have both, but the latter type converts to a male coax adaptor... do they make a female type, that I can attach a shielded cable to directly?
 

·
Registered
Joined
·
1,570 Posts
Pariah69,


You can get a barrel-type balanced to unbalanced (balun) transformer with a female connector. You could snip and strip the wires at both ends of the little "Y" shaped connectors. Then twist each of 300 ohm downlead wire to one of the balun's wires and cover it with black electrical tape. You shouldn't need to do any soldering.


Jim
 

·
Registered
Joined
·
1,058 Posts
You should use the little box thingie and just cut the wires almost as short as possible to reach the terminals, maybe allow 3/8 inch extra for slack.

You will need of course a male-male adapter.



I have not found the round barrel type to work well AT ALL. The

square semi-barrel type with the male connector on it and the rubber

boot works great if you cut off the boot and cut the wires on it and

the antenna so again you have only about 3.8 inch slack. If you leave

too much wire you will get a poor impedance match and signal loss.


I did a lot of wok on these things with a good network analyzer.


Doug McDonald
 

·
Registered
Joined
·
391 Posts
I drilled the rivets out on the bowtie and used two small screws w/washers to connect the little transformer.The RS model has spade connectors on one end and male coax on the other.Works the nuts:D
 
1 - 6 of 6 Posts
Status
Not open for further replies.
Top