domenica 25 ottobre 2020

Chinese Very Low Cost RF Amplifier 1-1000 MHz - 2.5W

I have recently bought trough Wish an amplifier 1-1000 MHz - 2.5W .
There was no other specifications , but the cost was so low ( 12 Eu ) that I couldn't resist .
During the first preliminar tests I saw some derating with temperature , so I added a big heatsink recovered from an old PC CPU .
The setup of the measurement is in the following pictures .
Adding a 30dB 20W power attenuator at the input of the spectrum analyzer , the power measurements in dBm was translated in dBW.

With no power at the input the amplifier drive a current of about 260 mA at 15V.
First I tried the low signal gain with an input power from the tracking generator of about -20dBm  adding a 10dB attenuator at the output of the tracking generator .

The result is shown in the following picture .

The gain is very high at 100 Mhz @ 47dB , @  52dB at 1 MHz and @ 30dB at 1 GHz .
So the flatness is around 22 dB peak to peak ....
There is also a negative peak at 52 MHz probably due to some resonant element in the decoupling of the circuit .
Being specified as a power amplifier , I have then increased the level of the Tracking generator till @ 3dBm to measure the response in saturation .
The results are shown in the following pictures .

Power is in the region of : 

@ 3W at 100 MHz current about 482 mA 
@ 2W at 500 MHz current about 380 mA
More than 0.5 W at 1000 MHz current about 375 mA 

Flatness is now about 6dB peak to peak .

I have made some measurements of the output spectrum at single frequencies to have an idea of the harmonics as shown in the following pictures .

At 100 MHz everyone can recognize something quite similar to the spectrum of a square wave 

500 MHz 

 1000 MHz ( frequency at 500 MHz comes from the generator that use a doubler inside ) 

I am very happy about the results of  this device with a cost of 12 Eu .

Associazione Radioamatori finanzieri - siamo in Aria

 Eccoci in "aria" fino a dopo Natale 

Abbiamo iniziato con l'appuntamento domenicale

(ad eccezione dei giorni di duro contest)

poi abbiamo pensato :

Ma perchè dobbiamo accontentarci della domenica mattina????

Unitamente a questa bellissima iniziativa :

- da venerdì 16 ottobre 2020
- a domenica 27 dicembre 2020

ci saranno "sparsi" nelle frequenze radioamatoriali (rispettando il BAND PLAN) diversi nominativi appartenenti al nostro sodalizio 

Coloro che collegheranno o ascolteranno (swl),nel periodo sopra citato almeno 7 (sette) soci  (Elenco completo dei soci A.R.F.I.) potrà richiedere al nostro award manager IZ8SKD  un'attestato PDF a ricordo

Ci saremo più che altro nel tardo pomeriggio ed alla sera .... date un'occhiata ai vari DXcluster  

Buoni ascolti/collegamento da  Francesco Giordano

IZ1KVQ - ​Genova

se ti va visita il mio sito

Grid: JN44LK

CQ Zone: 15

ITU Zone: 28

QSL: Bureau, Direct (no contributi), eQsl (, e-mail or Lotw 

 il mio link su QRZ

lunedì 19 ottobre 2020

Il Sole ha fatto qualche altro piccolo "ruttino" - Occhi alle aperture in E sporadico

Dopo l'ultimo sporadico evento segnalato  all'indirizzo :

il Sole ha fatto qualche altro piccolo "ruttino" ....

Radio Events Observed 07 Jun 2020
A.  245 MHz Bursts
Start  End   Peak Flux  Time of Peak  Duration
0025   0025    100          0025        0000  
0026   0026    120          0026        0000  
B.  245 MHz Noise Storms
No 245 MHz Noise Storms Observed.

Radio Events Observed 18 Oct 2020

A.  245 MHz Bursts
Start  End   Peak Flux  Time of Peak  Duration
0251   0251    110          0251        0000  
0243   0244    100          0244        0001  
B.  245 MHz Noise Storms
No 245 MHz Noise Storms Observed.

Occhio alle aperture in E sporadico .

giovedì 8 ottobre 2020

SAQ Grimeton Transmission on October 24th, 2020

On the United Nations Day, October 24th, 2020, the SAQ transmitter in Grimeton will again send out a message to the whole world on 17.2 kHz CW

16:30 (14:30 UTC): Startup and tuning of the Alexanderson Alternator SAQ.
17:00 (15:00 UTC): Transmission of a message from SAQ.
17:20 (15:20 UTC): Live music concert from the transmitter hall.
Anna Louise Ekman will perform Swedish and Italian songs, accompanied by a pianist.

The entire transmission event and the following concert can be seen live at our YouTube Channel starting at 16:30 (15:30 UTC).

Enrico Guindani, IZ2NXF

martedì 6 ottobre 2020

Klingenfuss Publications

Dear friends,

 currently, more than 500 Kiwi-SDRs are available at , and most of these cover the entire HF spectrum. Consequently, monitoring and decoding of professional HF digital data stations - from exotic locations all over the world! - is more convenient than ever before. Hundreds of screenshots will be published in our brandnew 2021 editions. See dozens of samples on our hotfrequencies website!

We've passed the solar cycle minimum in 2019, and propagation conditions are improving fast: on 5 October we received the low-power transmitter of aircraft ET-AVB, an Ethiopian Airlines A350 at an altitude of 41,000 feet enroute from Addis to Dubai, sending automatic position reports every few minutes on 21955 kHz. HF radio continues to be fascinating!

We're now working on our new products


- 2021/2022 Guide to Utility Radio Stations

- 2021 Shortwave Frequency Guide

- 2021 Super Frequency List on CD

- 2021 Frequency Database for the Perseus LF-HF Software-Defined Receiver

to be published on 10 December 2020.

Full-resolution title page graphics can be found at and and and


If you are able to supply additional new frequencies and stations, your cooperation would be highly appreciated. Please let us have your data by 20 October 2020.

The continuously updated product Digital Data Decoder Screenshots on USB Stick now covers more than 19,000 (nineteen thousand!) screenshots from 1997 to today. Feed your PC or Tablet with this data, and the "slide show" will keep you busy for a few days - or weeks!

Shortwave is dead? Well, we've been told so ... for 52+ years. More than 900 selected new digital data decoder screenshots will be published on our 2021 Super Frequency List on CD ;-))



Latest references (see


Jeff Krehbiel NZ5GI, United States of America - 30 September 2020:

"2019/2020 Guide to Utility Radio Stations ... Radio Data Code Manual

... 2020 Super Frequency List on CD ... I received my shipment weeks

ago and I just realised I never let you know I got it! I am

completely happy with everything - the magazines were a fun bonus!

Thanks so much for all your work in putting these things together and

making them available."


Stephen Jarvis, United States of America - 2 August 2020: "2019/2020

Guide to Utility Radio Stations ... 2020 Shortwave Frequency Guide

... Radio Data Code Manual ... 2020 Super Frequency List on CD ...

books have been outstanding."


Frederick Beihold NV1N, United States of America - 30 June 2020:

"2019/2020 Guide to Utility Radio Stations ... 2020 Shortwave

Frequency Guide ... Radio Data Code Manual ... 2020 Super Frequency

List on CD ... Radiotelex Messages ... Double CDs with Modulation

Types ... Broadcast and Utility Databases ... Entire order received

in good condition. It's a pleasure ordering products from your



Michael Hanlon, United States of America - 13 and 14 May 2020: "I am

now restarting my hobby and I am very excited to be able to place an

order with you! Even though the SW band has changed dramatically in

the last 30 years, there is still something magical."


Michael McConnel, United States of America - 13 March 2020:

"2019/2020 Guide to Utility Radio Stations ... 2020 Shortwave

Frequency Guide ... Radio Data Code Manual ... Radiotelex Messages

... Double CDs with Modulation Types ... the books and disks arrived

yesterday ... can hardly put them down, fascinating reading ...

wishing you all the best in your radio efforts."


John Smith K3GO, United States of America - 9 March 2020: "I have

been using your shortwave and utility books for 39 years. I fondly

remember the first booklets and my primitive teletype serial port

computing equipment before we had Windows and GUI. You do a great job

... I wish you the best for all you do for the hobby community."





Best wishes, Joerg Klingenfuss

Klingenfuss Publications

Klingenfuss Radio Monitoring

Hagenloher Str. 14

72070 Tuebingen


Phone +49 7071 62830

Fax +49 7071 600849

Bruno Pecolatto



venerdì 4 settembre 2020

GPS Jammer measurements

I have made some instrumental measurements on a GPS Jammer in the laboratory on L1 and L2 frequency bands .

For the frequency definitions for GPS bands see at :


Please note that the use of this devices on air is strictly forbidden .

giovedì 3 settembre 2020

Kiwi SDR - Born to be remote stand alone 10kHz - 30 MHz

Kiwi SDR is a very smart product easy to put in remote without any PC .

Just plug an antenna , a GPS antenna , if you like , power supply and network connection and you will have a fully remore station that allow till 4 users at the same time .

There are already more than 400 RX around the world that can easily accessed without password or software installation .

It has also very interesting decoders and special functions .

One is TDoA , Time Difference of Arrival  .

Using three or more stations you can find the place where a signal comes .

Here you can find alla the links to understand and three pictures of the test I have done receiving and locating the 77.5 KHz DCF77 station . 

lunedì 31 agosto 2020

Baudline - Un Software Spaziale ... ?

Mi sono imbattuto in questo "strano" software sviluppato nel corso di dieci anni .

Da quanto si deduce dal gruppo twitter viene anche usato in ambiti spaziali :

Di sicuro sono persone che la sanno lunga sia di teorie dei segnali che di programmazione .

Le funzioni sono vastissime e ben documentate .

In particolare esistono un paio di funzioni che , dalle foto darebbe risultati " esaltanti" .

Ecco due esempi mirabolanti , prima e dopo , che onestamente non sono in grado di giudicare , ma ho gia' sguinzagliato un po' di persone giuste .

Dove sta l'inghippo ? Gira solo su Linux a Mac OS .

Magari qualcuno di voi e' in grado di vedere se con Wine o qualche emulatore si puo' ovviare ....

domenica 30 agosto 2020

Adalm Pluto RX in odd harmonic mode at 10 GHz


Adalm Pluto Local Oscillator is square wave , it is possible to use it in odd harmonic mode . Here is shown how much is the attenuation, tuning at 3333.333 MHz and receiving at 10 GHz (25 dB) .

Other posts and measurements  on ADALM PLUTO here :