Oscar 100 and DATV

Activity is surprisingly low on the narrowband transponder of this geosynchronous satellite. There is (at least) one DATV net via the satellite, transforming amateur TV.

There are some very clever people around!

Oscar 100 - worst yet?

It has never seemed this bad. The photo shows the narrowband transponder on a European weekend morning. Where is everyone? 

Stations on Oscar 100 at 1010z

UPDATE 1012z: A little better, but still very under-used.

Oscar 100 wideband transponder spectrum

UPDATE 1020z: There appears to be better use of the wideband transponder on Oscar 100. Although there is a spectrum display (see photo), I am not aware of a site with DATV streams. If so, I do not know of it.

See https://eshail.batc.org.uk/nb/ .

Apparently (this was news to me) there is a weekly TV net on Oscar 100 on Thursday nights at 2000z. 

See https://batc.org.uk/live/oscar100net . This link streams the results. I must check this out.

DX DATV experiments

According to the EI7GL blog, some amateurs are proposing to experiment with DATV on 10m and 6m.  Some DX is possible. I presume this is with much reduced bandwidths. 

Being within existing amateur bands, no special permits are needed. In the UK special permits are needed to experiment at 4m or 2m with DATV.

See https://ei7gl.blogspot.com/  .

DATV in the Netherlands

According to a piece in Southgate News VERON is encouraging operators to demonstrate DATV (digital amateur TV) on 2m in August.

See http://www.southgatearc.org/news/2020/july/datv-in-2m-band-on-august-22.htm#.Xw6884jYq00

TV webSDR for Oscar 100?

Although I regularly check the narrowband SDR at Goonhilly in Cornwall, I am not aware of the equivalent for amateur TV signals. I know there are various standards and this may make such a RX difficult. I am aware of the SDR showing activity levels in the wideband transponder, but not actual TV signals. If you are aware of one, please let me know.

By the way, activity on the narrowband transponder still seems low.

See https://eshail.batc.org.uk/nb/

CQ-DATV mags free

See http://cq-datv.mobi/ebooks.php .

CQ-DATV is available for free download. I have not tried amateur TV but some remarkable results are being achieved by DATV in the 146-147MHz band. Like all things in our hobby, you can only do so much. I think the use of digital techniques has given amateur TV a new lease of life.

2m digital TV

At the moment I am doing a test over a 7 mile path with G3KKD who has a 1W 2m digital TV TX.  The signal is getting across the path, but too weak to decode. We are about to try a different 2m antenna at my end. G3KKD wants to try the path to Luton (he has a friend Arthur there) but wanted to try this shorter path first. There is a core of keen DATV experimenters all trying to reach each other.  I am not sure if anyone in the UK is using the 4m NoV band for digital TV tests.

UPDATE 1652z:   Success!  Using Ian's 3el 2m antenna on his portable mast we were able to see pictures well over the 7 mile path with 1W DATV on 2m. This means my antenna or feeder are not working correctly. When I swap to a big-wheel or big-wheel stack with new feeder it may well perform better than I expect.

Four Metre Band and OFCOM rubbish decisions?

There was an announcement on the RSGB and OFCOM sites advising some UK full licence holders that 70.5 to 71.5MHz is being made available for one year by special permission for further digital experiments, a bit like 146-147MHz here in the UK.

Sorry, but has OFCOM gone stark raving mad???

I can see no good justification for this 1MHz of spectrum. 2m was already under-used and the 146-147MHz allocation is probably being used by a tiny handful of people from time to time only.  DATV tests could quite as easily happen at 70cms.

I can think of far better parts of the spectrum OFCOM could have allocated e.g 100kHz around 40MHz (for Es propagation experiments), 73kHz, below 8.3kHz and a contiguous 5MHz allocation. Oh no, these require a brain to be engaged by OFCOM people.

Maybe this is an April fool's wind-up, although  I suspect it is true.

Surely if OFCOM wants to further real experimentation in radio science there are better ways of going about it?  Yet again, I am totally unimpressed. Between OFCOM and the RSGB, I think this is, yet again, a stupid stupid decision. So we now have 2MHz of extra spectrum for 12 months that a very few might use. Big deal. OFCOM, engage brains, think radio science. If you want to help grow future engineers that we so badly need, these allocations will not help at all. Think again!

See http://www.rsgb.org/ .
See http://www.70mhz.org/ .