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 This area must have the worst reception in town!
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 Return to top of page · Post #: 1 · Written at 4:06:21 PM on 26 June 2019.
Vintage Pete's avatar
 Location: Cromer, NSW
 Member since 1 May 2016
 Member #: 1919
 Postcount: 1050

AM Reception is hopless, the light globes interfere with it, the AC voltage interferes with it , wfi, too from the neighbours.
So if I switch off all the lights and every device that uses AC it improves and of course night time is a little better but it's shocking.
The unit is clear sounding as I had disconnected the antenna and ran it back into ground on the chassis to check ...unit is s very quiet unit !! Excellent!
Tried a ground wire around the yard , tried one up the trees , best one is in the ceiling.
I hope the next house I live in has good reception. I'm just about over the reception here... Its a bit like Gillians island.......pete


 
 Return to top of page · Post #: 2 · Written at 6:05:07 PM on 26 June 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 5262

Tried a ground wire around the yard , tried one up the trees , best one is in the ceiling.

I think you mean to say an aerial wire.


 
 Return to top of page · Post #: 3 · Written at 6:24:17 PM on 26 June 2019.
Vintage Pete's avatar
 Location: Cromer, NSW
 Member since 1 May 2016
 Member #: 1919
 Postcount: 1050

Yep GTC ....long wire about 25 feet of it... Pete


 
 Return to top of page · Post #: 4 · Written at 9:18:22 PM on 26 June 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3702

Had a look on Google Earth: Have a look at Wangandary Vic. Almost total opposites.

You can experience all of the benefits of regulatory authorities who have totally lost the plot & basically do not give a stuff about any form of compliance. Some of that interference I get. Gradually I have weeded out, or nobbled, that which likes to generate inordinate amounts of RFI.

Where you are in trouble is from the multitude of Wall Warts that charge phones, computer peripherals, and other things that use switch mode power supplies, or regulators. I have pointed out that I have returned LED spotlights to point of sale as one wiped out AM the other FM and AM. So compliance was obviously never entered into by the regulators with that. One lot did actually get caught out submitting one thing then selling it without suppression, but that was probably a once in a "Blue Moon" detect. Compact Fluorescent Tubes are notorious for RFI . The Whirlpool Fridge in the kitchen has LED lights and its PSU wipes out any radio near it. So we are fighting a loosing battle as long as we have useless regulators.

Wireless NBN has to be turned off to calibrate a radio, but at least its inside the Metal Studio where a certain amount of its shenanigans can be dealt with. I get RF riding on the mains & that has been dealt with. Mains grounding is not such a problem as most of it I have arranged to be in creek beds, underground water streams, or areas that will remain damp, that ensures that I will not get earth rods etc, arcing in dry ground.

Most of the old radios were, as noted, designed for 25 feet. Workshop / Studio is closer to 50m & is on poles. I do like the communications receiver, it has an antenna tuner. One of the things I never do unless there is a fault, is to peak the antenna coil with anything other than an antenna coupled to it. It may be worth a try to reset it that way, if it was not done that way? Weak station around 1500KHz.

Loop antenna's are directional that may help? Pay attention to the primary of the antenna coil ideally it should go to a good ground. High rise building grounds can be a problem as they act as antennas. A non grounded metal chassis in a transformer set can be an issue as there will be a poor RF return for the antenna coil and a shielded transformer can cause hum & place a charge of several volts on the chassis.

Getting rid of interference can be a hard and some times impossible slog.

Marc


 
 Return to top of page · Post #: 5 · Written at 8:50:59 AM on 27 June 2019.
Vintage Pete's avatar
 Location: Cromer, NSW
 Member since 1 May 2016
 Member #: 1919
 Postcount: 1050

Marc,
Yep a loop may work better . I watched a doco where a guy made a nice one with Cooper pipe.
LED lights and wfi seem to be the worst for reception dramas that's for sure.
Modern radios work better here , but still pretty crappy
Frustrating because a lot work goes into the old chassis and it's disappointing when the reception is so crappy in some areas.

Pete


 
 Return to top of page · Post #: 6 · Written at 4:04:00 PM on 27 June 2019.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 5502

If you want dirty power, come to a hospital. Medical equipment spits out lots of it. The one I work at has something like 40,000 light fittings, 30% are LEDs and another 10% are older halogens with electronic transformers. The rest are fluorescents of about 15 different types. Then there's around 400 televisions, an IP-based nursecall system, DECT phone network, DAS network for mobile phones, WIFI network plus standard copper telephony (digital and analogue), around 300 security cameras and a few computer/IT networks. Right outside the building there is a 132kV zone substation.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 7 · Written at 4:58:35 PM on 27 June 2019.
Vintage Pete's avatar
 Location: Cromer, NSW
 Member since 1 May 2016
 Member #: 1919
 Postcount: 1050

Nooooo thank you Brad,I'm keeping well away from hospitals...,but I think reception issues is far more common in newish buildings and homes, my last house was old and no issues with reception...pete


 
 Return to top of page · Post #: 8 · Written at 9:55:17 PM on 27 June 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3702

I sometimes wonder at the need for switch mode power supplies in LED lighting. No one seems to be game to quote the environmental cost & energy required to make a light with electronics, compared to a 100% recyclable incandescent globe? Being pure resistance it also has a better power factor than inductors & generates no RFI.

It a bit like paper bags & plastic ones: OK people are Pigs & they are an environmental menace; But we create another issue as we are already cutting down trees at an unsustainable rate & a lot more, rather than cheaper stuff, will go into bags.

We fix one issue & make another. With RFI as long as it does not upset mind addling entertainment for the masses & phones: Who cares. Regulators don't, now days their only underfunded window dressing & we suffer the consequences.


 
 Return to top of page · Post #: 9 · Written at 11:31:59 PM on 30 June 2019.
Wa2ise's avatar
 Location: Oradell, US
 Member since 2 April 2010
 Member #: 643
 Postcount: 724

Maybe the crud is getting into the radio via the mains. Using a set of LC circuits might mitigate it, see
http://www.wa2ise.com/radios/rfiradiofilter.htm




Here I cascaded two such filters inside an old PC power supply case (I kept the fuse in circuit to protect the coils from excessive current):


You might need a coil on the ground to block RFI from riding in, if your radio has a ground on the mains plug. For safety reasons you probably don't want to disconnect the ground.


 
 Return to top of page · Post #: 10 · Written at 11:53:57 PM on 30 June 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3702

My variant of that also sees 0.01μF caps, one from Neutral to ground and the other active to ground. Neutral now floats were there is an RCD (GFCI). Due to lightning mainly, there is also an MOV across Neutral & Active and one Active to ground. The latter to deliberately trip the RCD.

I see several commercial units here, now using that MOV idea. The main issue here other than lightning is RF riding on the mains from the long utility transmission aerials.


 
 Return to top of page · Post #: 11 · Written at 7:35:21 AM on 1 July 2019.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 809

Good ratting and scrounging skills to keep costs down.


 
 Return to top of page · Post #: 12 · Written at 9:20:35 AM on 1 July 2019.
Vintage Pete's avatar
 Location: Cromer, NSW
 Member since 1 May 2016
 Member #: 1919
 Postcount: 1050

Wow interesting....it's definitely coming from the AC in this house and the internal lights are the worst interference .At night if I turn all the lights off in the house I get far better reception. I also think it's wifi issues because when my neighbors are not at home the reception is also better. I imagine the old IF coils in vintage radios are not designed for the amount of new interference that we get in the modern world from wifi and led lights.
Yes the unit has a Earth and is 3 pin plug , the unit is a kriesler 11 77 and with the aerial disconnected and run to ground on the chassis to check for noise it's dead quite! Good clean unit so it's interference issues only.

Pete


 
 Return to top of page · Post #: 13 · Written at 1:33:49 PM on 1 July 2019.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 571

Pete, one of the things I did when I was investigating "Hash" in my AM signal was to go for a walk around the neighbourhood listening with a transistor radio, set between AM stations, and use that as a crude " indicator" of noise in the surroundings.
The answer was simply this: The closer I got to power lines the more HASH noise. Day and night.
In my location the HASH level almost is as high as the transmitted signal on the frequency of the only worthwhile AM station 2CH!

As your set is quiet with the antenna bridged to ground I don't think the hash is breaking through the coil shielding.

If there was no hash coming through the mains, then your weak signals would be much clearer, that's just the fact of a signal to noise ratio.
Therefore as Marcc and the other guys have pointed at, reducing the hash coming through the set power cord has got to help.

Unfortunately old radio sets are not fully contained in metal boxes sealed to RF (except comm receivers) but even so the application of 240 VAC rated capacitors, Movs and chokes at the point of cable entry is worthwhile. The other easy thing to try is the good old FERRITE RING either clamped (split core,) or the cable threaded through the ring for a few turns.

Just to repeat, the background noise comes from the MAINS, from every switchmode supply in every piece of electronics ever made and every overloaded line transformer in the system.
.
Back in 1960 (here we go folks) I could use the mains as a CLEAN SINUSOIDAL reference 50 cycle signal with better that 1% harmonic distortion and a noise level down on the floor somewhere. The only disturbance in the system were the off-peak heater signals and the occasional crappy overhead insulator. A resonant filter could wipe out the off peak signals and a choke and capacitor cleaned any other sproogles out. Household loads were mainly resistive, the only inductive loads were the washing machine and a couple of fans all drawing symmetrical power.

Now in 2019 the mains waveshape is a harmonic laden furry mess and its out of control and the imported RF rubbish just overpowers low level AM signals. Household loads draw inductive or capacitive loads, both symmetrical and assymetrical with pulsing and chopping injecting hash at all frequencys. The only way of getting away from it is to go to another planet where all power is hydraulic!


Hmmmmmmmmmmmmmmmm.

Fred..





 
 Return to top of page · Post #: 14 · Written at 2:03:24 PM on 1 July 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3702

There was discussion on earths / grounding, I think in Silicon Chip, but some on the Forums.

It is known that earth rods can arc in the ground and in some cases with the effluxion of time. lose efficiency. That has been mentioned by me frequently. When upgrading here care was taken to ensure that the grounding was in optimum locations (like an old creek bed). The best I had, prior to moving, was a bore casing.

I did have a FAX /Telephone get into a 175KHz IF. But it seems now that any thing with a switch mode PSU, or electronic ballast, is a source of RFI. Line caps, as described before, MAY, Help? But every electrical wire in the house, is a potential antenna.

Worst RFI device in the place are the Wireless NBN devices.

Marc


 
 Return to top of page · Post #: 15 · Written at 2:15:08 PM on 1 July 2019.
Vintage Pete's avatar
 Location: Cromer, NSW
 Member since 1 May 2016
 Member #: 1919
 Postcount: 1050

G day Fred,
Yeah I can go for a walk with one of my old Am radios and see how we go.
Strangely today the reception is very good for some reason although I have not change anything.....well that's a great sign regarding my chassis.
The are no telegraph wires and poles in these streets it's all under ground .I've never lived in a street with no telegraph poles before! I bet the local Dogs miss the poles! He he.

Across the radio dial there are many stations I receive but 2ch is the strongest and the only one worth listening too, but that's ok. Most don't play music anymore. This radiogram is my favourite and it gets a huge amount of use , Basically if I'm at home it's playing ..I just love it!
I always wanted this model and I rebuild the chassis replacing every cap and resistor. I then got my friend Ian Robertson to check it for me .I had made a boo boo with 2 resistors getting my colours mixed up so they were replaced and all went great and it sounds wonderful like old valves do !!!
Pete


 
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