BATC Forum

I use an old Sandpiper helical beam for 23 cms, mainly for it's wideband nature, it used to work well into the IOW repeater
until they lost their site. I even worked DL on SSB with 10 watts with it.

- Charles

There was also an interesting discussion during the "BATC CAT12 - Antennaes and Baluns that work" presentation.
Posted on BATCOnline YouTube channel.

My 5.6GHz gear is coming together, a bit of a rats nest but it seems to work ok. Just need an aerial now, where does the best deal guys?
73 Dave.

Me too Are aerials cheaper than 5.8 GHz coax relays??

Gareth

Gareth,

A 2.4GHz version of the helical would be useful for an Es'hail-2 uplink. Does the material cause any loss? A minimalist version would also save on 'ink'.

Brian

I'm going to microwave a sample today and report back. The www is surprisingly vague about the RF properties of PLA.

*** And the great news is that it seems unaffected. 1 minute in a 800 watt microwave with a cup of water, plastic came out stone cold. So it seems suitable for RF....how much of a helical would be good for an uplink? I can search for existing designs or possible do the cad to enable reliable replication. **

Gareth

Sounds good. There'll be some dielectric effect, so the bare minimum of supporting framework would be best.

There's some info here on a helical feed for offset dishes: http://www.g6lvb.com/60cm.htm

Around 5 turns seems to be optimum, but if the framework could support 6 turns, it would allow for experimentation. I wonder if it could be made so that it could attach to the standard 40mm LNB holder?

There's more info here, including a design for prime focus dishes: http://www.w1ghz.org/antbook/conf/Helic ... tennas.pdf

ISS and Es'hail-2 use RHCP, so the helical feed should be left hand to allow for the reflection off the dish face: anti-clockwise when viewed from behind the ground plane.

Brian

Weather radar stations on 5.6GHz.

Select Band=C and Country=United Kingdom and click on the dot at the centre of the circle to get the frequency. It might explain some de-sensing if you're near one or beaming at one.

Brian

http://eumetnet.eu/wp-content/themes/ae ... index.html

need recommendations for an sd card reader WITH AV output - all I can find are usb ones - any ideas please ?? - or types to look out for on flea bay or I am a zonion ………………. thanks

Hi,

Try media player in your search; there are loads about and it's what I use.

https://www.ebay.co.uk/itm/Full-HD-1080 ... SwUchaBB~n

73 Steve