[MrFixr55]

Me again.  Te following link is to an article explaining all the runs, changes and permutations for the Model 89, except Ron Ramirez's conversion from a 36 or 77 to a 6A7 Pentagrid convertor:

Evolution of Philco Model 89 – Philco Library (philcoradio.com)

[Bruce B]

I checked the a antenna signal can be tuned in all up and down the dial. It's when you remove the signal it is replaced by louder noise all up and down the dial.
This morning I took the radio for a road trip to a building I own 5 miles away from my house. The radio became quite quiet and tunes in stations ok.
If interested I have posted two videos of at my house and at 5 miles away.

At my house
https://photos.app.goo.gl/iY3jZX9h2mokeAFo7
5 miles away
https://photos.app.goo.gl/foux4nTd1zT3t6Ab7

I have called the power company and they are going to check it out. They told me that they have had trouble with lightning arresters with arced over capacitors that were damaged in a recent lightning storm we had. Hope that's it, because my new hobby is fun when you can't operate a radio in your house. This interference is so strong it completely prevents any AM radio from receiving a radio station.
I am for now going to focus on returning the power supply to original design, it's a mess. Don't know why it's working. I don't need to worry about coils and interference to do that.?
OH! That video on oscillations and beat frequency to explain a superhet radio was cool, I did like it, thanks
Bruce B

[Bruce B]

Please excuse me because I am easily confused. I just posted a video that was to demonstrate the interference I am getting at my house. Ops, wrong video. This is the one I wanted to post.
https://photos.app.goo.gl/K3QMHjtuYpFF19k77

[Chas]

That is the sound of an inverter, generally a Solar Panel. However, SCR devices can make that type of broadband signal to.

Does this sound come in on other AM radios in the same location?

Do you have a battery operated transistor portable radio, a larger size preferred?

Does the sound come in on that radio too?

Many other modern household appliances with computer like function panels can generate that form of noise.

With the portable radio one can hunt for the sound, the long ferrite antenna is directive so turning the radio and walking at right angle of the radio at its loudest will direct one to the noise source.

Go to this link at the ARRL:

http://www.arrl.org/radio-frequency-interference-rfi

There you will find other links telling you how to find the noise problem and how to fix problems is the home.

Over the past few years, I have been plagued with RFI on 40 and 80 Meters.  Most of it has been Horticultural lighting, (read that as Grow Lights). The power supplies for the LED's in these lights are the high power switching type. Similar to that in a computer...

I am a Ham and experience noise issues all the time.

The linked remark about lightning arrestors can often be identified as a "tail" hanging out of the porcelain body of the arrestor. The inside is smoked with blown apart metal and it is arcing inside.

A bad arrestor, insulator, transformer can create a noise that travel for miles on the high lines... Clamps to the connections of the arrestor can generate noise if they are loose...

Chas

WA1JFD

[Bruce B]

This is not coming from my house. I used a battery powered modern radio with a Faris antenna.  This interference is everywhere within blocks of my house.  I live on a country road with no close neighbors. I can drive half a mile down the road, get out of the car and my test radio will start screaming if I get within 4 feet of the power Pole's ground wire.  I have to drive at least 3/4 a mile away to no longer here anything with my test radio. This also is a new development, not present weeks ago.  I discovered it after turning on this new project of mine. Now I have found that no AM broadcast radio will work in my vicinity if it is adjacent to electrical wiring.  That also includes blocks down the road from me.  I tried to use my test radio as RDF but this interference is not really in the air it's radiating from the hardware of the power company and you don't hear it if more that says 40 feet away.  I drove around yesterday quite a bit and determined that over a mile away the noise is basically gone.  I placed my battery radio next to a dozen different power poles around where I live a get a loud buzz.  One place is on the other side of the river my farm is on and about 1500 feet away.  It's an abandoned farmhouse but there is an active meter there that I guess is for a well pump for cattle.  My radio would scream when I went up on the porch of this empty house and at the porch light the radio got quiet loud.  Anyhow I'm about done with it, it's them, not me.  DS&O Electric is coming out tomorrow to find out what's happening.  I have a radio transmission line coming right up my driveway.  Thanks for the info on tracking down interference  sources.  I will be studying it tonight
What Chas says is about what the power company guy said to me today when I called them.  A recent lightning storm 2 weeks ago he said damaged several arresters . Well fingers ? crossed they will come right out, find it, and fix it.  I was having fun with my new hobby till I found that I can't practice it at my house.

[GarySP]

I feel for you, Bruce. A few months ago I had an issue with my florescent lights not operating when switched on. Checked at my panel and found 118 volts on one leg, and 104 on the other. DTE sent out a tech to look into the problem. Three hours later he returned to tell me he found the problem, and it was resolved. The issue was a poorly installed transformer lead on a pole 4 blocks away from my home. The whole grid was in a semi brown out. Take care and BE HEALTHY! Gary

[Chas]

Bruce,

Ah! So RF noise is not in your home...

H'm, the RF can be so strong that it is impossible to determine if one is observing a node and that farmhouse, the actual source is some distance away.

Please elaborate "Faris Antenna" please. A Google search came up with a variety of antennas but none appear to be the "sort" applicable to RF locating. Unless I have missed something, I want to learn of what you used.

I have a General Electric battery portable MW radio often referred to as "Super-Radio 1". If has a long internal loop-stick antenna and is relatively directional.

It is this G-E radio I used several times over the years to find RF noise problems in my suburbia area. In one instance after notifications to the Power Company it took some 6 weeks of on-off visits of several crews including the "RF" boys. I do not disturb them unless they call at the house. The last crew came with the cherry picker. I suspected something was going to happen, I took the G-E outside with me and sat under the pole across the street one pole down from them. They tackled the arrestor, (live) with hand tools and gloves. A couple of turns of the wrenches and the noise on the radio stopped... This was some 7 years ago. A remark from the technicians was that the power company had determined that for fewer lightning damages all "dead" ended lines had to be terminated into an arrestor. A third party contractor did the work, that was some two years previous it took that long for poor workmanship to fail...

When I was still employed in the early 90's I had a position in R & D where I was performing repairs on a sensitive Infra-Red motion detector. Seems it was randomly triggering. By poor design the cable though shielded to the sensor was functioning as an antenna. The timing from the sensor was vital so any external traps delayed the pulse... At that time a local Ham radio friend was also head of the RF interference dept of the local power company. So He and a partner answered the call and put there assortment of instruments to work. They found a loose joint on the 3-phase primary side of the buildings HUGE power transformer.  Since it was on the building side, a local electrical contractor took apart all the insulation, dressed and reconnected, re-insulated. Problem solved.

The power company has much more shielded radios for RF sniffing with reference antennas.  They also use direction ultrasonic conversion microphones. High voltage leaks often generate ultrasonic hiss...

Solar panel installations as well as Electric car charging has brought in a whole new round of RF issues.

GL

Chas

WA1JFD

[Bruce B]

Chas,
I meant ferrous.  I'm old, blind, and I use the drop-down spell assistant too much without looking.  I see you are a ham and know that a ferrous antenna is directional.  I however had no luck at RDF tracking.  This noise is everywhere and I have to be somewhat close to some hardware for my radio/RDF tracker to detect it.  I can hear the buzz standing under the power lines but 15 off to the side it's gone.  At every power pole however the radio screams loud.  I'm betting on a lightning arrester but where?  I hope DS&O has some of the equipment you were speaking of.  We will see tomorrow.  BTW in 1967 I became WA0UKB  67 to 77 2 tickets then quit. Don't know why.  Now I have a thirst to play with an old superhet like I used dig out of the trash back in the 60s
88s and I'll be back.
Bruce B

[Chas]

I'll take pix of the pole at the end of the street to identify a lightning arrestor. Dark now and there is a LED light that blinds the camera...

   

I looked online for a pix but many of the images are mis-identified and are on transmission lines, not the 7200 circuits.

Strangely, though I am subscribed to several radio forums, that, often make use of ferrite in many forms, I have never experimented with a ferrite loaded antenna. My preference is for vintage wire loops, I have several loops and radios built with them.

Though for most RF noise issues the portable radio works but it seems that in very strong sources a well shielded radio and a means to disable the AVC and having a calibrated "S" meter is employed...
Good luck tomorrow...

Chas

[Bruce B]

Well the utility company came and listened. Then worked for about 3 hours around the area trying to figure it out but couldn't. They think it's a lightning arrester. They quit looking and said they will be back after they find some kind of radio they have somewhere. I'm afraid this situation might be above their understanding. They didn't seem to relate to radio frequency principles but they were very nice and said they would get to the bottom of this.
Bruce B