Monday, 31 August 2009

VHF radio from Camperona Mount


The car and fire watchman's house on background

The car and the antennas

Close-up of the moxon antenna





Saturday, 29 August 2009

QSO with CT2JTZ

After some failed tryes, I have been able to contact with CT2JTZ

Monday, 10 August 2009

Visit to CT

Last thursday I received a phone call from EA1DK, Fernado told me he had been QSOing with CT2JTZ Thierry who is Telecomunication Engineer(like me) is keen on mirandese language(me in leonese, both are same languages with different local names)
It was a big coincidence because I had planned to travel to Braganza next day just few km away from Thierry, so I decided to find out info about him and visited him.
I arrived Thierry's town on Friday afternoon and I met him! He was surprised for the visit. We spent a nice Friday with him, he show us his town, the petroglyphs, even invite us for dinner at his home(tks to his mother)
Next day 22 I hope to visit him again.
Here is a photo from my visit:


Why I use the CT7 prefix?, read this

Tuesday, 29 July 2008

DL8BEG reproduces EA1GHE`s downconverter

I have received an e-mail from Werner(DL8BEG) who successfully reproduced the downconverter that I designed to receive DRM with the kenwood TS-450S radio.
Werner found a mistake I made in the drawings(now corrected):

Thanks to Werner for his correction.
This is a photo from his circuit:

Sunday, 22 June 2008

Recycled ferrite sleeves from the rubbish

There is one cheap way to get ferrite sleeves for EMI troubles. Get the sleeves from old computer screen cables. Just use a knife and extract out the ferrites.

Monday, 26 May 2008

Receiving DRM with Kenwood TS-450S (II)

For those who are interested in receiving the DRM using the TS450 radio by Kenwood, here is a pdf file with the details and circuit. Remember it's also valid for TS690, TS850 and TS950 radios wich has 4th IF output at 36.891KHz for use with optional DSP-100.
I am waiting for any feedback.
73!
Here is a demo video:

Saturday, 5 January 2008

RF interference from Sony TV set

I had a Sony TV set model KV-14M1E. Every time it was turned on(even in stand-by mode) I received an annoying QRM from it in my amateur radio. Since I know that the interference came by radiation one day I decided to open the TV and explored the circuit with a small loop probe. You can see how I did it in the next video:



I discovered two loops radiating RF:


Like a solution I was thinking about decoupling these loops with the right capacitor but I had got no time to do the modification, the TV set was taken away from my QTH.
Now my spectrum is clear, more or less, of human-made QRM.