Messages

46

22 Meter Band HiFER Beacons / Re: Using a 20m Yagi for reception

« on: February 24, 2020, 1125 UTC »

The most important thing I have found for receiving antennas and in particular for weak signal work is to guard against common mode noise. I am not sure how a Yagi will behave so far away from its design frequency, but would expect it to be rather inefficient, and with quite unknown directional response. However, if you can be sure that noise on the outside of the coax feeder doesn't add to the signals picked up by the elements (use of a good balun etc.) then the antenna could do well enough if also away from local noise. Since it is there, you might as well try it!

One of my receiving antennas is a "random wire dipole" made to fit the available space, with about 45 ft on each leg. At the centre connection to the coax I used a home made balun with separate primary and secondary windings, built on a binocular ferrite core. I think the transformer is an important part of the success of the system. Common mode noise on the coax is horrendous, but is completely absent in normal use and the system is great for 22m beacon reception. I have a long wire also connected in a similar manner, using an isolation transformer between aerial and earth points at the antenna, and the signal and shield of the coax. Similarly, this also does well in keeping the house noise out of the radios.

Cheers

Ed

47

22 Meter Band HiFER Beacons / Re: 22m Beacon

« on: January 21, 2020, 1826 UTC »

Sounds like you are on the right track IZS4

I have experimented with a couple of antennas, starting out with a 1/4 wave vertical plus radials, then (and most successfully in terms of reports) an inverted V type dipole. Both setups were mounted on the house roof.

Cheers

Ed

48

22 Meter Band HiFER Beacons / Re: 22m Beacon

« on: January 10, 2020, 2032 UTC »

As Chris stated, the regulation is based on field strength. That equates, IIRC to about 2 mW into a vertical, or 4 mW into a dipole. Of course, what you are able to put up for an antenna will have some bearing, as will the local environment, on losses. But there's no point, obviously, in an antenna with gain. For a beacon, you want relatively uniform radiation in all directions anyway, to maximise the chance of reception.

The restrictions are pretty tight, but that is what seems to make HiFERs fun to many of us who operate and listen at 22 m.

Cheers

Ed

49

22 Meter Band HiFER Beacons / Re: Beacon PVC temporarily off

« on: December 15, 2019, 1906 UTC »

PVC restored 

I found a broken wire at the mast head balun. The system must have taken a real beating in the storms. Also had to repair/replace the guy wires. Now opearating at the usual signal strength, as verified from a nearby receive antenna.

Cheers

Ed

50

22 Meter Band HiFER Beacons / Beacon PVC temporarily off

« on: December 13, 2019, 0054 UTC »

Hi Folks,

Beacon PVC, 13,555.55~ is temporarily off air until storm damage to the antenna can be repaired. I'll update accordingly.

Cheers

Ed

51

22 Meter Band HiFER Beacons / Re: Beacon reception

« on: October 29, 2019, 1929 UTC »

Beacon PVC active here in California. 13,555.55 kHz. Often it is turned off at weekends so that I can listen without being swamped.

HF propagation isn't being kind to beacons much of the time at the moment. Do try for the hours before and after sunset, there can be a lift in conditions during this period of the day.

/Ed

52

22 Meter Band HiFER Beacons / Re: 22 meter beacons outside the US (and England especially)

« on: September 10, 2019, 2304 UTC »

SWL,

A quick search turned up this Ofcom document:

https://www.ofcom.org.uk/__data/assets/pdf_file/0022/103297/fat-ism-frequencies.pdf

Alas, early on this states:

"In the United Kingdom the use of ISM apparatus is allowed provided it does not
contravene the provisions of the Wireless Telegraphy Act 2006. The International
Telecommunications Union defines ISM in the Radio Regulations as:
“industrial, scientific and medical (ISM) applications (of radio
frequency energy): Operation of equipment or appliances designed
to generate and use locally radio frequency energy for industrial,
scientific, medical, domestic or similar purposes, excluding
applications in the field of telecommunications.”

I found more of the same at this location for UK frequency allocation Again the Wireless and Telegraphy act is cited, but I have not had chance to try and decipher that particular document:

http://static.ofcom.org.uk/static/spectrum/fat.html


I suspect that any intentional radio emission with the intent of reaching significant distance is forbidden, but have yet to find proof.

Ed

53

22 Meter Band HiFER Beacons / PVC reaches Kansas!

« on: April 09, 2019, 1641 UTC »

Hi folks,

I received word that my beacon, PVC (13,555.5~~) was picked up by a LWCA member on 2nd and again on 3rd April, late in the afternoon in Kansas. That is a record distance of approximately 1400 miles for this station

Apparently there has been an indistinct trace visible several times at the same frequency, but this was the first occasion on which a positive ID could be made. You can read more at the LWCA website  https://www.lwca.net/mb/index.html, and if you are a member, there is a screenshot from Argo and a recording available.

I was just about to abandon the sloping dipole in favour of constructing a new 1/4 wave vertical antenna, but think I'll leave things as they are for a while longer.


Cheers

Ed

54

22 Meter Band HiFER Beacons / AZ heard Sunday 8:20 am (PST)

« on: February 04, 2019, 2156 UTC »

I had an unexpected early session at the listening desk yesterday(Sunday Feb 3rd). AZ (13,554.0~~ kHz) was making it to California quite audibly during the half hour after 8 am (PST). Inaudible, but detected via spectrogram, were NC and E H, operating in slow FSK mode as usual. One other feint trace may have been USC, but could not be read clearly.

Beacon PVC was temporarily disabled by a couple of power outages, but is currently in operation.

/Ed

55

22 Meter Band HiFER Beacons / Re: Why "anonymous" beacons on 22 m?

« on: January 11, 2019, 2214 UTC »

That's a good point, Prariedog, I don't think anyone would know to put up a 22 m beacon without having encountered HFU or LWCA etc. - After all, why would one run a beacon without being able to know if it was received elsewhere?

On the other hand, some value privacy to a high degree.

56

22 Meter Band HiFER Beacons / Re: PVC off temporarily

« on: November 30, 2018, 1844 UTC »

PVC back on air!

57

22 Meter Band HiFER Beacons / PVC off temporarily

« on: November 29, 2018, 2121 UTC »

Hi Folks,

Had to remove connections to PVC's antenna today when thunder and lightning jolted me awake!

I'll restore operation ASAP.

The storms also dragged my long-wire aerial down again. That is the second time this week...

Cheers

Ed

58

22 Meter Band HiFER Beacons / Re: Your best clear spots in the 22 m ISM Band?

« on: November 19, 2018, 1730 UTC »

Last week I brought the Lowe HF150 in to the office. It has a sensitive Hi Z active antenna input. Alongside a few carriers within ISM limits, was a massive broad-band hash from all the other equipment and lighting circuits. In fact this was plenty audible with the whip antenna switched to the straight 50 ohm input. I didn't get chance to monitor from outside the building.

One last thing - There was a nice clear dasher signal.. traced to the NFC/RFID transponder of my smart-phone!

59

22 Meter Band HiFER Beacons / Re: Your best clear spots in the 22 m ISM Band?

« on: November 12, 2018, 2154 UTC »

That is an interesting supposition Exo.

Since I work at a manufacturing facility that uses RF generators, I could ask. It is also a perfect excuse to bring the portable listening setup to work

60

22 Meter Band HiFER Beacons / Re: 13 MHz Western USA Beacons

« on: November 09, 2018, 0243 UTC »

Nice report Exo. Over the weekend, I was able to copy AZ, and also a number of the beacons clustered around 13,555.xxx. The slower mode signals visualise nicely using Spectrum Lab in QRSS3 mode. I have a screenshot, but need to work out how to include it in a post...

Ed