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Monday, 27 January 2020 13:09

Amateur TV through Satellite QO-100 - Updates

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Since I first blogged about my QO-100 setup I've made a couple of changes, it was always going to happen.

First to be upgraded was the dish, I had chosen a 1 metre because I didn't think the shack manager would authorise anything bigger. When she heard I was getting mediocre results the outlook changed and I soon took delivery of a nice new 1.2 metre aluminium Gibertini. Actually it wasn't nice because the courier laid it face down and stacked every heavy box he could find on top of it. Having looked forward to installation I was gobsmacked.

My supplier immediately set about packing a replacement, this time he got some wood and made some bracing for it. How annoying that the dish had survived the trip from Italy and the UK based courier had destroyed it, I was so sorry for the seller.

For a while I remained custodian of the bent one while the seller negotiated with the courier. Photo's were sent and I don't know what the outcome was except that my local scrap collector had the biggest grin when he arrived to collect it.

So the new one arrived in perfect condition in a white finish, it's the standard colour but you can get grey or brick finish to special order. As you can see in the picture below I made an awful job of spraying it brown, I chose matt brown because it doesn't reflect the light like white.

Results are much better than the 1 metre but my dual feed is a compromise, I wish I could use the 1 metre for receive and the 1.2 metre for transmit, I'm told this isn't possible because it will interfere with the rotary washing drier. Say no more.

On a good day the QO-100 beacon has an MER of 8dB so I don't do too bad. I also manage a pretty good 2 M/s signal into the satellite using the new PA in the last blog.

So the other change was to fit a switchable attenuator to the front panel of the driver section. This is a used 10dB step attenuator I bought through eBay, manufactured by Tamagawa. Excellent value and there's a load of them at just over £15.00 each at the time of writing. There's a picture of my spare one below.

An attenuator was needed because I’m now able to go overpower on the satellite. A click or two of the attenuator keeps me out of trouble. Pity so  many others on the satellite can’t conform.

Credit to Tony at Hisat for his efforts to get a dish to me undamaged. Look him up for a good deal. Hisat.com

73 Steve

My 1.2 metre Gibertini. Changes since the photo are LNB clamp modified (ground) to allow fitting of a straight feed connector, previously right angled. There's also a cover over the LNB / Feed assembly using a piece of inverted plastic gutter, picture below.

 

This is the enclosure for the PA driver and filtering seen in an earlier blog, now with the addition of a step attenuator.

 

Tamagawa 10dB step attenuator, came complete with lock washer, washer with locating tab, nut and collett knob. Some of the ebay sellers were selling the attenuator without fixings or knob.

 

Guttering is clamped to the 22mm feed tube using easy to buy plumbing fittings from Screwfix.

Read 231 times Last modified on Tuesday, 28 January 2020 16:01

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