R8600 ICOM R8600 antenna port #3 - Making it useful

prcguy

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Take a dipole antenna's 450 ohm _balanced_ ladder line and terminate it into a unbalanced 450 ohm port? That's like taking a Mercedes 4WD G-Wagon, lowering it and installing hydraulics to make it jump. Abomination. :LOL:
Ooh, a lowered G wagon, that would also need a little chrome steering wheel made out of welded chain. And something fuzzy hanging from the rear view mirror. You would want Ali G to be your chauffer.

Anyway, a 200 ohm(ish) 1:1 balun at the radio will help using a balanced antenna to an unbalanced antenna input. You probably wouldn't notice any difference compared to a receiver with balanced input.
 

dlwtrunked

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But the 8500 has poor specs, especially compared to the 8600. The 8500 did a lot, just not very well.
Of course the R8600 is a lot later and should do better. For its time the R8500 was a nice radio and used a lot by government agencies. It had particularly nice audio. Anyway, out of here as the thread police who kill interesting RR discussions have arrived.
 

Teotwaki

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Anyway, a 200 ohm(ish) 1:1 balun at the radio will help using a balanced antenna to an unbalanced antenna input. You probably wouldn't notice any difference compared to a receiver with balanced input.
So if you have to use a balun it can be 9:1 and allow the use of 50 ohm coax. That goes back full circle to the underpinning message of this thread and avoids the issue of getting ladder line through a wall or window
 

Teotwaki

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I thought about modifying one of my 8600's but I ended up winding a balun and mounting it all in a small aluminum enclosure instead. I leave that connected to that 8600 and use it when comparing antennas across the HF spectrum. It works very well.
Being external, I can easily move it to the other 8600 is needed.
Having antennas on two different front panel selected inputs can be very handy. I wish Icom would have allowed the use of all three inputs (or at least Ant1 and 2) for the 30 MHz and above ranges.

I meant to ask you about how you physically connected the 450 ohm side of the balun to the phono port. Any pictures? I didn’t have any sort of male bulkhead mount phono connectors to go on a metal enclosure. I ended up not wanting to impact the 450 ohm “match” with any sort of coax cable connected to a male phono connector that plugged into the radio.
 

ArloG

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Wow. I think someone woke up with a bowl of Wheaties that had a tinge of salt and ammonia.
Time was when I could stuff a length of wire in the BC348Q and throw it out the window and be happy spinning the dial into the night when everyone else was asleep. And later on the same with my other boat anchors.
Random wire tossed out a window or tied to the neighbors downspout on the USAF base.
I didn't know anything about baluns, unun's, Nor did I really care.

I was the same. Never ever used ladder line. Still should try it before the sun quits rising for me, I guess.
When the 450 ohm catch phrase came up here and I Googled '450 ohm impedance coaxial cable'.
Ladder line was the result.
If noise on bare wire gets your fur all ruffled and your tail looking like a bottle brush. Ferrite beads?
A common mode choke? Take a trip wayyyyy out in the woods with a battery. And for heaven's sake.
A few six packs of Sammy Adams and California's finest. Sheeh! We don't need no stinkin' moderators.
 

Teotwaki

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Somebody should put a ferrite bead on their warrior’s keyboard cable and relax. 😆😆😆

I’m out in the desert while remote controlling my two 8600’s and listening to fighter jocks over China Lake with my handheld scanner
👍👍👍image0.jpeg
 

prcguy

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Somebody should put a ferrite bead on their warrior’s keyboard cable and relax. 😆😆😆

I’m out in the desert while remote controlling my two 8600’s and listening to fighter jocks over China Lake with my handheld scanner
👍👍👍View attachment 183263
Don’t make me grab my 8600 and park next to you in the desert. My antenna will be bigger than your antenna.
 

Teotwaki

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Don’t make me grab my 8600 and park next to you in the desert. My antenna will be bigger than your antenna.
As long as it is a bare wire covered in Micrometals or Amidon ferrite beads and jammed into a phono connector I’m cool with it. LOL
 
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