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Old June 27th 19, 07:18 PM posted to rec.radio.shortwave
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First recorded activity by RadioBanter: Sep 2017
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Default FM antenna


+AD4 I used to think something like that. But losses in transmission,
+AD4 scaled down, are losses in receiving as well. Just that you have
+AD4 AGC - and therefore rather impressive changes in RF/IF gain - at your
+AD4 disposal to swamp out so many of the receiving losses. Until you get
+AD4 down to the noise floor, at which point antenna gain becomes important
+AD4 in the same way it is in transmitting.

I think the biggest factor in an antenna's signal to noise radio is going to be it's directivity. Inefficiencies will generally reduce both the signal and received noise floor equally. Inefficiencies will introduce also introduce noise on their own but I think it would take a super quiet location to notice the difference.

Just consider the untuned loopsticks commonly used on portables nowadays. They work pretty well when they're square to the signal or nulling out an interfering station.

+AD4 Mine died quite some time ago. Guess I need to start
+AD4 replacing capacitors.

One note on those old electrolytic capacitors rated in +ACI-working voltage+ACI or +ACI-WV+ACI. Working voltage was a goofy, old-timey convention which I think was related to the circuit's voltage AFTER the tubes warmed up. If a cap is rated 160WV, I think a modern 200V cap is a good substitute. 250V might be better.

I have some of those Xicon caps rated at 150V that AES sold. They have a bad reputation with some people. I'm not using them at more than 120V peak and they seem to be holding up OK. A nice safety margin is cheap enough these days.

I fired up my 60 year old B+ACY-W dip meter a few months ago. It worked fine, no hum. It's a low end dip meter but they used decent electrolytic.

I picked up a Heathkit with no coils for cheap. That one is in the +ACI-round tuit+ACI pile.

+AD4 Then there's that Heathkit Tunnel
+AD4 Dipper I found at a swap meet. Might even work. Now if
+AD4 I knew what box I put it was in when I moved...

Hey, the Tunnel Dipper is a collectors item, as I understand. Good luck with it+ACE


+AD4 The top of my old Harmon Kardon receiver is probably
+AD4 reasonable, though at +AH4-18+ACI wide it is not nearly as
+AD4 good as a typical refrigerator.

I'd like 1/4 wave in all directions. I've settled for a refrigerator top.

+AD4 I vote for a 2' x 3' quad, 18-22 AWG, glued to the back
+AD4 of a slightly larger, preferably framed, movie poster.

Movie poster? Maybe Kinko's will print up a poster of this:

http://i140.photobucket.com/albums/r...iCastroAdS.jpg

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