VK Logger Ham Radio Forum Archive

Hi,
over the last 18 months or more I have noticed that my noise level on 160 metres has risen to over S9 much to my disgust. We have neighbours either side of us but they are not close (on 10 acres here) so had put it down to a case of some one buying a new but noisy electronic device, sigh another band lost to me.

A recent extended power black out allowed me to connect my FT 817 to the 160 metre antenna and I could see the band was quiet . . . Ah there is hope but every thing returned to noisy once the power came back on

Now, a little back ground, next to the house we have a shed that houses our satellite internet dish, router and network switch, a second shed further away from that, has our stables and my shack. The house, shed and stables are all connected via multiple underground CAT5 cabling for Ethernet, intercoms and control signals for lights.

The satellite equipment is powered from a small 240 -> 24vDC brick that has not been changed in the last 12 years but it turns out that this was the culprit of my noise. I had assumed it was not a problem as it had been quiet in the past but No, it had developed some form of mild fault that was wiping out the low bands of HF and was detectable up to 50MHz.

I have recently built a linear power supply for the satellite equipment, it also powers the router and the network switch. This has made a HUGE improvement to my noise levels and now find my self chasing those elusive fish net beacons on 1.8MHz now I can finally hear signals again.
http://www.genesisradio.com.au/VK2DX/fishnet.html

Moral of the story for me, never trust a switch mode power supply

Would love to hear others experiences.

Regards,

Tiny SMPS running the clock in my shack went crook one day. Brought the noise level up to an objectionable level on the broadcast band for about 100m in all direction.

running all switch mode supplies in the shack and the whole house is lit with LED lighting and so far have had no problems with noise or interference. Cheers Graham

I have a white noise issue on 10m (comes and goes).... currently S8 at QTF 70.... gone 20 degrees each side.... is over our roof and towards our neihbours (also in semi rural area - 5+ acre blocks)....time to look for an SMPS?!

Sent from my SM-G900I using Tapatalk

Hi,

I had a problem at xmas with a new noise source wiping out 2m band, pulsed at a 2 second rate. Only on at night.

Traced it to a set of solar powered blue LED lights i had put up outside as decorations. a Very nice noise generator.

Jim VK3ZYC

Hi,
here are some specifics from my last few months of investigation, avoid the PowerTech range of voltage selectable plug packs, the one I have is horrid (was from the outset) and has just been replaced by a linear 12 volt supply, the Model I have is: MP 3316, I think it came from JAYCAR.

Also try to avoid the POE (Power Over Ethernet) injectors from Ubiquiti networks, model: GB-B240-100, it generates noise (swoosh-ing noise across the band) up 150 MHz.

I seem to have mislaid the 24V switch-mode (might have already gone to recycle) but will edit this post if I find it as it was the culprit of my wideband noise on lower HF.

Regards,
Peter.