.

Ο λόγος στασίμων 1:1 ενός κεραιοσυστήματος, δεν συνεπάγεται τον 1:1 λόγο μεταφοράς ισχύος, προς την κεραία!

Wednesday, 17 August 2016

RCA 813 QRP transmitter!


The well-known radioamateur motto dictates to Listen, Listen and Listen again.
Since the presentation of the GU-81 regeneration receiver you had your chances to listen enough.


Now its time for you to transmit!
I'll give you the initial kick along with photos and the schematic for a QRP Tx based on the 813 tetrode tube!
Gentlemen, (and Ladies of course), warm your irons!


Μετά τον δέκτη ανάδρασης με την GU-81, τώρα κι ο ανάλογος πομπός.
Αυτοταλάντωτη 813 με κρύσταλο και QRP ισχύ εξόδου! (λέμε τώρα!)

Friday, 12 August 2016

5KW Electronic Variac.


What you see at the picture is a commercial AC 220V 5000W SCR Voltage Regulator Speed Controller Dimmer, ebay item number 171786606530. That with an AC 0-300V Round Analogue Dial Panel Meter ebay item number 231936883787 and a PC p/s box Tolis sv1edy gift, makes an excellent electronic variac!

I removed the power supply board from the box and opened the necessary holes using my laser guided hand file. The result is what I call the best possible given the circumstances!

Now I can start old radios with no fear of possible damage due to inrush current!
Or reform electrolytic capacitors.
Or vary the speed of power drills and motors.
Or wherever...

Another one bites the dust!




Another one balun bites the RF!

Wednesday, 27 July 2016

Tx Factor - Episode 12


Not one, but two rig reviews: the Sun Expert Electronics Transceiver MB1 and the elusive Icom IC-7300 are comprehensively analysed.

Bob teaches Mike a thing or two about amateur satellite operating, and our free-to-enter-draw is back with a chance to win a copy of the Getting Started with Amateur Satellites book featured in the item.




Και μία ακόμα περιληπτική παρουσίαση του IC-7300!

Thursday, 21 July 2016

Visit kalamata... visit beautiful Greece (4K UHD cinematography promo)



Summer indolence has cast a heavy veil over me. Happy holidays everybody and in a few weeks I'll be back here!


Η θερινή ραστώνη έχει ρίξει ένα βαρύ πέπλο πάνω μου. Καλές διακοπές και σε λίγες εβδομάδες, θα είμαι πάλι εδώ!





Sunday, 17 July 2016

Δράττομαι της ευκαιρίας!


Δράττομαι της ευκαιρίας να χαλαρώνω στο αρκούδι-sion αφού στο εργαστήριο κάνει ζέστη και είναι απλησίαστο.
Μοιράζομαι μαζί σας μία εικονίτσα-οδηγό για την ζωή, όπως και μία τέταρτη παρότρυνση.
Μην ξεχνάς.
Γενικότερα! 

Tuesday, 12 July 2016

Audio stage of a homebrew TxRx!



I've built a bare bones audio amplifier using an LM386. No volume control other than Gain control. It will be embed to a bigger project in time!


Βασικός ακουστικός ενισχυτής με το LM386. Μέρος ενός σχεδιασμού ο οποίος θα υλοποιηθεί σιγά-σιγά.

IARU HF Championship 2015


Failure. Due to family matters I couldn't stay on the radio most of the contest resulting a mere 96 contacts, 2.751th position-10.452 pts and position 13th in my category. A contest for the darkest place in my closet.


Ωσεί παρών σε αυτόν τον διαγωνισμό με αποτέλεσμα μόνο 96 επαφές. Καλύτερα να το ξεχάσουμε το θέμα και να πάμε παρακάτω όπως στον φετινό όπου το ευχαριστήθηκα πραγματικά!

Contest Mode!


As usual, I run the IARU HF Championship contest past weekend. I slept only 3 and a half hours, 00:30 UTC to 04:00 UTC and I manage a total 236 contacts! Interestingly the bands, all of them, were alive. Propagation do us the favour and the Sunspots were a good 56. I was using a logging program this year and things were running smoother and faster. I have already upload my contacts and all I have to do is to wait for almost a year for the results! My antennas are a EFHW wire and my work horse Create -730V having its legs extended by 17 metres of wire each side! 10 European contacts on 80m band but none on 160m.
Until next year then with a better setup!

Επαφές μπορεί να μην έκανα πολλές αλλά έμεινα συνεχώς στον διαγωνισμό εκτός από 3 και μισό ώρες ύπνο. υπήρχε πέρασμα σε όλες τις μπάντες παραδόξως αλλά υπήρχε και φοβερός ηλεκτρικός θόρυβος, Α=35. Μου λείπει μί α κάθετη κεραία την οποία έχω και θέλω να ανεβάσω αλλά, πόσα να κάνω μόνος μου;!

Monday, 4 July 2016

[GQRP] Sunspot Numbers


I haven't had much to say about the monthly sunspot numbers for a while, but things have taken a dramatic turn in the past few months. The botton has fallen out in sunspot activity, and the average sunspot count for last month was a mere 20.9:

http://www.home.earthlink.net/~christrask/Solar%20Activity%201600-2100.pdf
As you can see, this has been the lowest sunspot cycle since 1885, and for those of you over 50, you've seen the best there is going to be until 2060 or thereabouts.

I wonder what happened to those NASA and ARRL experts who were claiming not too long ago that this was going to be the strongest sunspot cycle of all time?

Chris Trask
N7ZWY / WDX3HLB
Senior Member IEEE
http://www.home.earthlink.net/~christrask/


Εγώ τα έχω πει κι επιβεβαιώνομαι από Αμερικανούς συναδέλφους, των οποίων ο λόγος έχει κάποια βαρύτητα!
Θα πέσουμε "χαμηλά" για ν'  αναδειχθούμε!!!