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Base antenna, High noise floor tips..

Oh wow!

This does change the perspective and no (I'm not) - anyone here offended by that mess would only be people like the Coax cops and perhaps a Stand in or two from "Home Improvement" ...

The ladder line just blows me away...

I'd like to know more about your feed thru from the siding - does the "plate" screw directly thru that? That may be an injection point for noise...

My though on this would be to make either "Choke of coax" as it comes off the mast pipe at the lead-in. OR somehow fashion a fish line setup that allows you to access coax from the inside of the mast. You fish it down the mast pipe hollow as if it were a shaft to shield the coax within the mast itself.
  • Drill a hole to fish out the coax by the lead-in "plate"

Take the MFJ, remove it, connect the coax directly to the A99, then FEED THRU INSIDE the mast pipe - down to and off the side of the mast towards the lead-in. Do your choke where you leave the hole inside the mast.

If THEN you need to make a breakpoint - you can install the MFJ closer to earth ground and somehow, just somehow, make the coax shield grounded there before it leaves the pipe...

the wall plate is just a plastic plate with cut out near bottom edge for the coax to go thru and a huge 1 1/4" hole to easily feed my uncut coax with PL259's on it. This then goes inside and up to the rigs.

1376F78B-7452-4874-8919-1AF1BB20083B.jpeg D773AABC-7F0D-422D-82B4-4BA3DC146E0C.jpeg

This is the bottom shot looking up at the mast to show the gaps. Currently the MFJ915 is not in use. It's in a box downstairs.

D230EAD6-BA8F-4BA1-A616-BC81E94DD936.jpeg

And this is the huge leftover mess from prior owners over the last who knows how long of wire up in the other corner as you noted earlier from TV antennas and such.

2F375F8C-6637-48E3-898A-10F9C22D4A68.jpeg
 
First thing is to rule out possible sources
Shutting power off may reveal the source. If nothing else it eliminates a lot. Unfortunately there are a lot of people around you. The source could be as simple as a neighbor with a cordless drill charger plugged in. It doesnt have to be charging a battery to cause noise, just plugged in. A ballast for a grow light will do the same though usually there will be a clear pattern of high and low noise levels. Could also be someone growing hydro veggies or microgreens at home.
 
So I put the MFJ915 inline. (As shown on 24" jumper that I had up there).

SWR with AMP on is now like 1.4 which is better than 1.6. The meter is swinging up quicker as I'm guessing the power is more up and out vs reflected back upon self.

still got same noise floor as far as I can tell.

Thinking snap on ferrite down by wall where coax comes in the house.

2C25DCF2-6CFA-49AA-A387-DAA49AFC38BD.jpeg

just about 2' short of the antenna with stretch to show you how close I am, but a hair to short.

FE91E133-B124-409A-BD70-C12E73468D88.jpeg
 
Then without being able to tie-off and ground or otherwise "bonding" all the metal flashing up on that roof, I can only imagine the noise and electrical "floating charge" that must be up there. Might be able to power another radio if you can somehow harness and rectify the power that stuff picks up and you can throw power from that into a device...

Don't endanger yourself - the hospitals are too packed already - so the effort of reducing noise may have to wait.
 
Then without being able to tie-off and ground or otherwise "bonding" all the metal flashing up on that roof, I can only imagine the noise and electrical "floating charge" that must be up there. Might be able to power another radio if you can somehow harness and rectify the power that stuff picks up and you can throw power from that into a device...

Don't endanger yourself - the hospitals are too packed already - so the effort of reducing noise may have to wait.


True

Just had a short qso on 38LSB with a guy about 25 miles away I normally chat with he said my audio was louder hitting him with S5 with amp off and 10-15w (voice peaks) with my stock 86v at about 9am on the RF power knob. He also sounded cleaner and less static with his audio.
 
The problem lies in what the antenna receives at the same time picking up that noise - even when it is considered out of band. The ferrite will only do so much and that's for a current flowing thru the coax at a range of frequencies the ferrite core is able to be reactive upon.

That may not equate to full noise reduction no matter how hard you try.

How is the DC ground at the station?

Not to endanger you, but to think this logically, can you use the mast pipe as neutral? You could easily be able to look for a neutral or Ground at the home outlet and double check the ohmic readings. This method is easy enough for the technician because it's how they can help determine ground currents and faulty GFCIs' that are false triggering with nothing in them. Not for the timid or feint of heart literally. But a simple ohmic check of the coax shield to mast shield and earth ground can solve a lot of this by ensuring you're bonded to ground.

You have a cold water faucet right outside in the shot - you can check ohmic right there from it to mast and not endanger yourself.
 
As long as pipe and everything connected to it will be part of the antenna do not expect miracles.
Mike

I hear you. May need another mount for the HF and Dual Band Roll-up, and get it off this mast. Might help too.

I ordered these Fair Rite Mix 31 off EBay from a ham guy. Pack of 6.

6B19EE86-B137-4D4D-B2E7-EF799735E68C.jpeg
 
The problem lies in what the antenna receives at the same time picking up that noise - even when it is considered out of band. The ferrite will only do so much and that's for a current flowing thru the coax at a range of frequencies the ferrite core is able to be reactive upon.

That may not equate to full noise reduction no matter how hard you try.

How is the DC ground at the station?

Not to endanger you, but to think this logically, can you use the mast pipe as neutral? You could easily be able to look for a neutral or Ground at the home outlet and double check the ohmic readings. This method is easy enough for the technician because it's how they can help determine ground currents and faulty GFCIs' that are false triggering with nothing in them. Not for the timid or feint of heart literally. But a simple ohmic check of the coax shield to mast shield and earth ground can solve a lot of this by ensuring you're bonded to ground.

You have a cold water faucet right outside in the shot - you can check ohmic right there from it to mast and not endanger yourself.

i do know from doing the electric recently the ground and neutral are tied together in the breaker box for all outlets.

I have the amp and HF rig on the 30/33 megawatt and the radio is on a separate 10/12 amp power supply. All plugged in the same outlet. The coax shield is ohm'd out from coax ground to power supply ground as I just checked that.

At my old QTH I had ground wires on the amp and HF gear tied to the groundrod just outside with the same mast and antenna. Seemed to help a tiny bit.

I really need to get the mast grounded to the dirt with a rod. Sure can't hurt.
 
This ferrite won't help. Wasted money.
That is way to go: http://www.karinya.net/g3txq/chokes/
You aim for areas marked green.
Mike
I agree with the coaxial choke route on single band antenna systems. I use wide band ferrite core chokes only on multiband antennas.
For CB it's simple - five wraps of coax on 4" PVC nipple.
 
This ferrite won't help. Wasted money.
That is way to go: http://www.karinya.net/g3txq/chokes/
You aim for areas marked green.
Mike

If I'm reading it right. 6 beads of the type 31 will get me Orange. Unfortunately I already ordered them. And for $15 I'll take the risk. Worse case I move them to my HF line before it comes in the house. The HF end fed has a counterpoise.
 

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