VK Logger Ham Radio Forum Archive

Hi all,

Sorry for headling grabbing subject line........

I am a newly licenced newbie and am trying to get my head around the 6 meter band. This forum is an enormous wealth of knowledge and I have thoroughly enjoyed wading through it (including the "robust" discusions!). I wanted to get your views on the following holes in my 50 Mhz. knowledge base:

- Is there in fact much activity (VK-ZL) up on 52-54 for me to work?

- It will be a while before I can get some aluminium up, so have I got a fighting chance with my multiband OCF dipole in the mean time (Icom 706 Mk. II G)?

- As early warning indicators, what cycle does the CW ident take on the 50 Mhz. beacons (continous or ever X mins.)?

- Speaking of early warning, if I am looking for TV audio do I search in FM mode?

- Confirming that USB is the default in SSB mode?

OK...I have bared my soul and donned my flame suit. I really would appreciate your top five tips for "us" newbies..

Hi Brendon,

My replies to your questions are:

There is some activity above 52mhz but most is in the lower part of 50mhz between 50.110 and 50.5mhz. Some operators will move to 52mhz if requested, others like myself will listen but I for one cannot transmit there due to high SWR from my 4 element beam. In this case you can work split frequency. You can use the logger to set this up.

When conditions are very good you can work 6mx with almost any piece of wire, but a resonant antenna, even a vertical, will give much better results. A 3 element beam is a good starting point.

There is no fixed sequence for beacon idents. Very few identify continuously but most do so at least every 30 seconds. Some give other info such as actual location or grid locator.

TV audio is wide deviation FM but using narrow FM will normally allow you to understand what is being broadcast. Narrow FM will be more sensitive when listening for weaker signals.

USB is the standard used on 6mx.

Others may have may have different opinions but most will agree that 6mx is a very interesting band with almost every mode of propagation being available at some time.

I hope to work you this summer season

Garry VK5ZK

Gary,

Thanks for the responce....all good stuff. It looks like I'll have to fast track a 3 el beam and be prepared to work split operations, if no Standard calls around.

Brendon
VK4MHZ

VK4MHZ wrote:Gary,

Thanks for the responce....all good stuff. It looks like I'll have to fast track a 3 el beam and be prepared to work split operations, if no Standard calls around.

Brendon
VK4MHZ

And if the bug bites, a reason to upgrade, you wouldn't need to worry about split operations so much.

Owen

OK..probably another "stupid newbie question"...but here goes

When I search for RTQ0 and ABNM0 video on 46.172/46.240, what are the audible characteristics of the transmission or do I need a tuner/monitor to detect and identify the video. Propagation wise, if the audio is there is it safe to say the video is too and vice versa?

Thanks

QSL Owen

Video carrier is a video carrier maybe a slight 50 HZ frame buzz and then sidebands swishing up and down the band every 15625 or 16525 or so I forget.
They are every where
57.240/250/260 138.250 87.250
55.250 in New Zealand
45.250 45.240
The weaker they are the cleaner they are.

http://home.vicnet.net.au/~vk3six/

Suggest you tune in a few and listen.

VK4MHZ wrote:... what are the audible characteristics of the transmission or do I need a tuner/monitor to detect and identify the video. Propagation wise, if the audio is there is it safe to say the video is too and vice versa?

The only dumb question, is the one that wasn't asked!

Steve sums it up, but they are nothing more than amplitude modulated carriers.
As our local TV system is PAL, you can hear a 50Hz buzz.

As one television line has a period of 64uS, you will hear sidebands every 15.625kHz.
These tend to taper off in strength as you get further away from the carrier.

There are also 312.5 lines per field (one TV frame consists of two interlaced fields), so you will hear a 50Hz buzz.
0.000064s x 312.5 = 0.02 s = 50Hz

Using audio spectral analysis, it is very easy to accurately measure video carrier frequencies, and whether the sidebands are 50Hz PAL, or 60Hz NTSC.
This becomes helpful as an early warning indicator.



Cheers,
Adam