Yes, it has bugs! Ugly, big bugs crawling allover the screen!
I do have some memory positions occupied by some frequencies. Around 100...
I cannot use several software to connect to the TNC. Looks like some initialising problems.
I was trying to access the TNC via USB commands and nada!
I also observed that very often I got the red "STA" message, which means that the TNC Buffer memory is full. The stacked frame is transmitted when I manually press PTT.
When I reset the radio, erasing all the memories, the "STA" problem is gone! Still cannot run the TNC from RMS Express and have trouble to use APRSIS32.
Another bug is related to the battery: After some charges the Batt. Indicator shows only two bars but the voltage is 8.32-8.36 which means a full LiIon battery. If the battery is removed and reinserted, the indicator shows full.
The firmware is 1.04.
Later edit: Still the same on 1.05.
Anyone with solutions?
25 noiembrie 2016
13 octombrie 2016
KENWOOD TH-D74
Deja comunitatea radioamatorilor vorbeste despre noua portabila Kenwood ca despre o mica revolutie in zona statiilor portabile.
Desi era greu sa mai vii cu ceva nou in ecosistemul Digital Voice, Kenwood a indraznit. Ne propune o portabila care combina FM, D-Star si APRS adaugand facilitati intalnite in zona echipamentelor profesionale.
Experienta Kenwood in domeniul audio isi facesimtita prezenta iar eticheta "Kenwood-JVC" cere, parca, un soi de rigoare si excelenta, pe care noua portabila pare sa le confirme.
PACHETUL
Contine statia, un alimentator in comutatie SMP de 13.8VDC/0.65 A (suficient pentru incarcare dar nu si pentru operare cu putere maxima), antena (aceeasi ca la TH-D72), un clips de centura de tip "clestisor", discret dar care lasa o impresie solida, statia propriu-zisa si un acumulator de 7.2V/1800mAh.
Avem un manual (pe care nu l-am deschis, spre rusinea mea), certificatul de garantie, toate impachetate in tiple.
AFISAJUL
Mic insa cu vizibilitate foarte buna. Fiind un TFT Transflective, are o buna vizibilitate pe timpul zilei iar pe timpul noptii se poate activa retroiluminarea.
MENIUL
Meniul se acceseaza cu tasta dedicata iar navigarea are loc cu tastele de directie. Structura imi aminteste de telefoanele mobile precursoare generatiei smart-phone, folosindu-se iconite pentru identificarea grupelor de sub-meniuri.
Kenwood a facut treaba buna structurand meniurile pe grupe logice, astfel ca setarile se pot face rapid si fara prea mare bataie de cap cu manualul de utilizare.
SUNT SUBIECTIV ACUM
Spuneam la inceput ca D-Star este sistemul ales de Kenwood pentru intrarea pe piata portabilelor DV. Mi se pare un pariu bun, standardul fiind bine pus la punct, Kenwood avand experienta din zona profesionala cu standardul CDMA spre deosebire de Yaesu care a improvizat C4FM dupa o aventura in zona profesionala DMR.
Combinatia D-Star+ APRS se pare ca era asteptata de multa vreme, portabilele ICOM avand standardul propriu de locatie cu ajutorul GPS (dPRS), incompatibil cu reteaua analogica.
Pe langa acest pariu DV, Kenwood a combinat in aceasta portabila si un receptor bunicel pentru SW si unul chiar bun pentru FM, amintindu-mi de motivul pentru care ma atasasem de TH-F7, receptia AM si SSB.
Primele incercari de a conecta BT la sistemul masinii au esuat. Mai am cateva trucuri de incercat inainte sa abandonez. Ar fi un mare plus daca as putea sa o folosesc in masina fara sa imi ocup mainile!
Meniul de ajustare a parametrilor audio ma face sa cred ca in interior are un "suflet" SDR, ceea ce ar fi si cazul la experenta si vointa inginereasca a Kenwood-JVC.
Pur si simplu, pentru ce este, statia suna extrem de bine!!!
Ca sensibilitate, in testele facuta in afara Bucurestiului s-a comportat mai bine decat portabila pe care o folosesc in mod curent si care este oarecum etalon: Icom IC E92.
In Bucuresti, in poluarea radio m-a surprins foarte placut! Suficient de sensibila (parca ceva mai bine decat TH-D72) si extrem de putin expusa la IMD! Aveam de gand sa utilizez atenuatorul in caz de IMD insa pana acum nu a fost necesar!
Pe ici pe colo lumea se plange de autonomia mica a acumulatorului. Putini tin cont de faptul ca acumulatorii compacti, moderni, de tip LiIon sau LiPol incep sa prezinte capacitatea maxima dupa un numar de cicluri de incarcare... Cu GPS-ul oprit, Battery Saver la 0.1s, retroiluminarea pe Auto 5 sec si la intensitate medie, acumulatorul la prima incarcare m-a tinut doua zile in ascultare de radio BC FM pe un VFO si monitorizarea unei frecvente de UHF in al doilea VFO. Evident, nu doua zile continuu dar niste ore bune in prima zi si ceva mai putin a doua zi. Apoi, in a doua seara am pus statia la incarcat.
Volumul de auditie este ridicat desi difuzorul este pe jumatate obturat de tastatura alfanumerica; in spatele sau montajul interior este astfel proiectat incat sa asigure o cutie de rezonanta.
Sensibilitatea microfonului este excelenta, modulatia fiind corecta si indestulatoare. Imi este clar ca exista o procesare discreta a vocii in cutiuta!
Spre deosebire de TH-D72, pe laterala gasim doar interfata USB nu si RS232 asa ca, "Adio AVMAP"!
Din fericire, pe acest port USB putem interactiona extrem de larg cu statia. Avem de ales intre placa audio USB sau iesire FI, putem folosi software-ul pentru programarea memoriilor care functioneaza in timp real, adica imediat ce modificam sau adaugam in tabelul de memorii, regasim modificarea in statie (ca la ICOM).
Intrucat am "intrat" in statie, pot sa va spun ca este solid construita si cu atentie pentru rezistenta la apa. Din nefericire, tastatura si difuzorul sunt parte din panoul frontal astfel ca o eventuala inlocuire a acestuia va scutura serios buzunarul. Ceea ce ne duce cu gandul la a gasi cat mai repede niste huse de protectie! Eventual si un incarcator tip Slide in.
MICI BAZACONII MAI MULT SAU MAI PUTIN UTILE
Balans intre VFO A si VFO B.
Inregistrare audio pe SD card. Din pacate, doar de pe un VFO, la alegere.
Doua taste cu functii alocabile de utilizator. Totusi, plaja functiilor este relativ limitata, asa mi s-a parut dar pana la urma am descoperit de ce nu se poate alege functia de SCAN pe aceste taste; SCAN se face apasand lung pe tasta de VFO sau de MR (memory), dupa caz... Mea culpa!
Statia poate fi utilizata ca tracker APRS dar si ca GPS LOGGER, traseul fiind salvat pe SD card.
Ah, de efect mi se pare posibilitatea de a modifica imaginea ecranului de start!
Ca si alte statii DStar, si la TH-D74 gasim o lista pre-memorata de repetoare DStar, care pot fi accesate corelat cu informatia GPS.
A'propos de GPS, acesta este unul dintre cele mai rapide pe care le-am vazut!
A mai ramas ceva? Nu stiu, daca mai gasesc, revin!
Filmulet de la aplicarea modificarii pentru extinderea de emisie:
Desi era greu sa mai vii cu ceva nou in ecosistemul Digital Voice, Kenwood a indraznit. Ne propune o portabila care combina FM, D-Star si APRS adaugand facilitati intalnite in zona echipamentelor profesionale.
Experienta Kenwood in domeniul audio isi facesimtita prezenta iar eticheta "Kenwood-JVC" cere, parca, un soi de rigoare si excelenta, pe care noua portabila pare sa le confirme.
PACHETUL
Contine statia, un alimentator in comutatie SMP de 13.8VDC/0.65 A (suficient pentru incarcare dar nu si pentru operare cu putere maxima), antena (aceeasi ca la TH-D72), un clips de centura de tip "clestisor", discret dar care lasa o impresie solida, statia propriu-zisa si un acumulator de 7.2V/1800mAh.
Avem un manual (pe care nu l-am deschis, spre rusinea mea), certificatul de garantie, toate impachetate in tiple.
PRIMA IMPRESIE
Statia este mai mica si mai compacta decat ma asteptam dupa ce am vazut-o in fotografiile de promovare.
Tastele au un feedback tactil destul de discret si, extrem de atractiv, au toate functiile retroluminate, spre deosebire de alte modele de statii portabile care au doar functiile principale.
Tastele sunt solide, nu din paterial plastic iar tastatura numerica are si o usoara inclinare despre care nu stiu daca vine din ratiuni estetice sau ergonomice.
AFISAJUL
Mic insa cu vizibilitate foarte buna. Fiind un TFT Transflective, are o buna vizibilitate pe timpul zilei iar pe timpul noptii se poate activa retroiluminarea.
MENIUL
Meniul se acceseaza cu tasta dedicata iar navigarea are loc cu tastele de directie. Structura imi aminteste de telefoanele mobile precursoare generatiei smart-phone, folosindu-se iconite pentru identificarea grupelor de sub-meniuri.
Kenwood a facut treaba buna structurand meniurile pe grupe logice, astfel ca setarile se pot face rapid si fara prea mare bataie de cap cu manualul de utilizare.
SUNT SUBIECTIV ACUM
Spuneam la inceput ca D-Star este sistemul ales de Kenwood pentru intrarea pe piata portabilelor DV. Mi se pare un pariu bun, standardul fiind bine pus la punct, Kenwood avand experienta din zona profesionala cu standardul CDMA spre deosebire de Yaesu care a improvizat C4FM dupa o aventura in zona profesionala DMR.
Combinatia D-Star+ APRS se pare ca era asteptata de multa vreme, portabilele ICOM avand standardul propriu de locatie cu ajutorul GPS (dPRS), incompatibil cu reteaua analogica.
Pe langa acest pariu DV, Kenwood a combinat in aceasta portabila si un receptor bunicel pentru SW si unul chiar bun pentru FM, amintindu-mi de motivul pentru care ma atasasem de TH-F7, receptia AM si SSB.
Primele incercari de a conecta BT la sistemul masinii au esuat. Mai am cateva trucuri de incercat inainte sa abandonez. Ar fi un mare plus daca as putea sa o folosesc in masina fara sa imi ocup mainile!
Meniul de ajustare a parametrilor audio ma face sa cred ca in interior are un "suflet" SDR, ceea ce ar fi si cazul la experenta si vointa inginereasca a Kenwood-JVC.
Pur si simplu, pentru ce este, statia suna extrem de bine!!!
Ca sensibilitate, in testele facuta in afara Bucurestiului s-a comportat mai bine decat portabila pe care o folosesc in mod curent si care este oarecum etalon: Icom IC E92.
In Bucuresti, in poluarea radio m-a surprins foarte placut! Suficient de sensibila (parca ceva mai bine decat TH-D72) si extrem de putin expusa la IMD! Aveam de gand sa utilizez atenuatorul in caz de IMD insa pana acum nu a fost necesar!
Pe ici pe colo lumea se plange de autonomia mica a acumulatorului. Putini tin cont de faptul ca acumulatorii compacti, moderni, de tip LiIon sau LiPol incep sa prezinte capacitatea maxima dupa un numar de cicluri de incarcare... Cu GPS-ul oprit, Battery Saver la 0.1s, retroiluminarea pe Auto 5 sec si la intensitate medie, acumulatorul la prima incarcare m-a tinut doua zile in ascultare de radio BC FM pe un VFO si monitorizarea unei frecvente de UHF in al doilea VFO. Evident, nu doua zile continuu dar niste ore bune in prima zi si ceva mai putin a doua zi. Apoi, in a doua seara am pus statia la incarcat.
Volumul de auditie este ridicat desi difuzorul este pe jumatate obturat de tastatura alfanumerica; in spatele sau montajul interior este astfel proiectat incat sa asigure o cutie de rezonanta.
Sensibilitatea microfonului este excelenta, modulatia fiind corecta si indestulatoare. Imi este clar ca exista o procesare discreta a vocii in cutiuta!
Spre deosebire de TH-D72, pe laterala gasim doar interfata USB nu si RS232 asa ca, "Adio AVMAP"!
Din fericire, pe acest port USB putem interactiona extrem de larg cu statia. Avem de ales intre placa audio USB sau iesire FI, putem folosi software-ul pentru programarea memoriilor care functioneaza in timp real, adica imediat ce modificam sau adaugam in tabelul de memorii, regasim modificarea in statie (ca la ICOM).
Intrucat am "intrat" in statie, pot sa va spun ca este solid construita si cu atentie pentru rezistenta la apa. Din nefericire, tastatura si difuzorul sunt parte din panoul frontal astfel ca o eventuala inlocuire a acestuia va scutura serios buzunarul. Ceea ce ne duce cu gandul la a gasi cat mai repede niste huse de protectie! Eventual si un incarcator tip Slide in.
MICI BAZACONII MAI MULT SAU MAI PUTIN UTILE
Balans intre VFO A si VFO B.
Inregistrare audio pe SD card. Din pacate, doar de pe un VFO, la alegere.
Doua taste cu functii alocabile de utilizator. Totusi, plaja functiilor este relativ limitata, asa mi s-a parut dar pana la urma am descoperit de ce nu se poate alege functia de SCAN pe aceste taste; SCAN se face apasand lung pe tasta de VFO sau de MR (memory), dupa caz... Mea culpa!
Statia poate fi utilizata ca tracker APRS dar si ca GPS LOGGER, traseul fiind salvat pe SD card.
Ah, de efect mi se pare posibilitatea de a modifica imaginea ecranului de start!
Ca si alte statii DStar, si la TH-D74 gasim o lista pre-memorata de repetoare DStar, care pot fi accesate corelat cu informatia GPS.
A'propos de GPS, acesta este unul dintre cele mai rapide pe care le-am vazut!
A mai ramas ceva? Nu stiu, daca mai gasesc, revin!
Filmulet de la aplicarea modificarii pentru extinderea de emisie:
13 iunie 2016
Setting up IC-7300 and Winlink Winmor TNC
SHORT TUTORIAL FOR WINLINK WINMOR AND ICOM IC-7300
By Adrian YO3HJV
1.
Download
and install USB driver from ICOM Japan https://www.icom.co.jp/world/support/download/firm/IC-7600/usb1_20/
2.
Go to the radio. Press “MENU”.
On the next screen, press on screen “SET”
Select with MULTI “CONNECTORS”. Press
MULTI. You will be now in the Connectors Menu.
Check the following settings:
ACC/USB
Output Select – AF
… Leave other settings default. Go down
with MULTI.
DATA
MOD – USB
USB
Serial Function – CI-V
USB
Send – RTS
Leave the SET Menu by pressing “EXIT”
untill the normal screen is shown.
3.
Connect the IC-7300 to the PC via USB cable.
The driver
will be automatically installed.
If you click on the USB icon, you will see
the progress for the USB Audio CODEC.
A few words about: The radio itself has a USB hub on wich a USB<>COM port and a USB
Generic audio board are connected. When you connect the radio to the PC,
the drivers will be installed.
The COM port driver is delivered by the
ICOM and the Audio board driver is
contained in a Windows update.
It will take some time to install the
generic USB Audio driver but be patience.
Also a driver for the USB Hub will be automatically installed.
Also a driver for the USB Hub will be automatically installed.
4.
Go on PC “DEVICE MANAGER” and check for the COM
port and the USB Audio board.
On my PC, the USB<>COM is identified as “COM7”.
Remember this because will be essential
on setting the WINLINK later.
Check the USB Audio board.
5.
Download and install the RMS Client Software
6. Follow
the instructions for RMS setup.
Here is an excellent explanation
of the Winlink system. Please read it to familiarise with the system:
Here is a tutorial for TELNET
RMS Express setup http://www.la3f.no/faste/digi/winlink/ExpressTutorial1130a.pdf
Remember that WINMOR is the MODEM (Lower layer) for the RMS (upper
layer).
7. Setup
WINMOR to work with ICOM IC-7300
Select “Winmor Winlink” and then “Open Session”.
Two more windows will open. One is the “Winmor
Sound Card TNC” and the second one is
the “Winmor Winlink session” .
On the second one, click “WINMOR TNC Setup”.
Search on
the combo box for some USB Codec and select it for Capture device (input to PC)
and Playback Device (Output to Radio).
Select “UPDATE”, the Winmor Winlink will
restart briefly.
Then, select “Radio Setup”.
Now,
make the setup just like in the picture below:
IMPORTANT:
Each ICOM radio has a default CI-V address (ICOM
Address). In my particular case, the address is 80 but yours might be 90 (The address is in HEX format!).
Click “UPDATE” and that’s all!
If, for some reason the radio seems to be unresponsive, just restart it without disconnecting the USB cable.
73 de Adrian
June 2016
14 mai 2016
APRS pocket transceiver bazat pe Arduino
M-am apucat sa experimentez cu un Arduino niscaiva traznai de APRS. Pana la urma a iesit un tracker care poate sa so receptioneze traficul APRS, inclusiv mesajele.
Transceiverul este un DORJI, v
ia LCCOM, placa uC este custom dar merge bine mersi si un Arduino UNO cu oarece componente pe langa ea. Cateva rezistente, condensator
i si un potentiometru. Comenzile la DORJI nu necesita curenti mari astfel ca un port I/O Arduino suporta fara probleme PTT ul.
Transceiverul este un DORJI, v
ia LCCOM, placa uC este custom dar merge bine mersi si un Arduino UNO cu oarece componente pe langa ea. Cateva rezistente, condensator
i si un potentiometru. Comenzile la DORJI nu necesita curenti mari astfel ca un port I/O Arduino suporta fara probleme PTT ul.
30 aprilie 2016
Antena dipol compact pentru banda de 60 m
Dimensiunile dipolului scurtat |
Am auzit in diverse discutii ca se intentioneaza evaluarea propagarii cu antene verticale, complet improprii efectuarii de legaturi la distante de 100-500 km in conditiile in care permisiunea de utilizare este pentru evaluarea posibilitatii de utilizare in situatii de urgenta pentru sprijinirea activitatilor de cautare-salvare.
Drept pentru care, solutia optima este utilizarea unui dipol la o inaltime de circa 0.20 - 0.25 din lungimea de unda, adica la circa 5-6 m inaltime. Aceasta ar fi inaltimea optima pentru a reduce pierderile in sol, dar este acceptabila pentru a beneficia de efectul NVIS si o inaltime de circa 3 m.
Pentru ca si eu, ca majoritatea radioamatorilor am probleme cu spatiul, un dipol de 2x15m este inabordabil (intentionez sa il amplasez in podul casei de la tara) , am realizat si testat un dipol scurtat, cu anvergura de doar 12m.
Sigur ca un astfel de dipol va performa mult mai prost ca un dipol full-size, cu circa 5 db, dar apropierea de sol reduce, de asemenea, si zgomotul captat pe unghiuri mici de radiatie, ceea ce nu este tocmai rau, avand in vedere ca testele se efectueaza pe teritoriul YO si nu la DX.
Solutia gasita pentru scurtarea lungimii electrice este introducerea pe fiecare brat al dipolului a unei bobine.
Realizarea practica este extrem de simpla si necesita o teava de instalatii, PVC, cu diametrul de 40mm, pe care vom bobina spira langa spira un numar de 42 de spire cu sarma de instalatie electrica izolata cu PVC, cu grosimea de 1.5 mm.
Aceasta bobina se va amplasa exact la jumatatea fiecarui brat al dipolului, conectandu-se la acestea cu borne tip papuc, sertizate pe conductorul radiant.
Incepem prin a taia doua bucati de fir de Cu multifilar de 1.5mm izolat cu PVC, de 3 m lungime. Acestea sunt cele care se conecteaza la izolatorul central.
Eu am folosit si un UnUn 1:1 (choke-balun)/
Taiem alte doua bucati de Cu multifilar tot de 1.5 mm dar in lungime de 3.5 m. Acestea vor fi legate la extremitatile dipolului, de la bobina la izolatorii de capat.
Pregatim doua bucati de teava PVC de circa 20 cm pe care vom bobina, spira langa spira, cele 42 de spire de Cu 1.5mm izolat cu PVC.
De aici incolo, fiecare isi va folosi imaginatia pentru a realiza conexiunile. Eu am folosit suruburi de 4mm cu piulite tip stea din inox. Peste bobine am aplicat un strat de banda izolatoare pentru imobilizarea bobinei.
Tevile au gauri pentru fixarea mecanica a firelor care constituie bratele dipolului iar ca element central am folosit un suport pentru dipol cu descarcator incorporat.
Evident, la capete se vor folosi izolatori ceramici sau de plastic cu striatii pentru a impiedica formarea arcului electric in conditii de umiditate.
Cateva date despre bobina:
Frecventa proprie de rezonanta: circa 21 MHz
Inductanta: 35 uH (necesar teoretic: 32 uH)
Rezistenta @5 MHz: circa 1350 Ohm.
Factor de calitate Q: circa 400.
Cu dimensiunile prezentate, nu a fost nevoie sa tai din fire.
IMPORTANT:
La capetele dipolului, lasati o bucla de circa 30 cm pentru fiecare brat; veti taia cate 1 cm pentru a obtine acordul antenei dupa amplasarea in pozitie. Masurata aproape de sol, frecventa de rezonanta va creste odata cu ridicarea in pozitia finala!
Cu dimensiunile prezentate, nu a fost nevoie sa tai din fire.
27 aprilie 2016
APRS at smallest footprint
Today I received the APRS modem boards.
They are made around a ATMEGA328 and can be programmed with Arduino IDE.
All they need is a small GPS and a transceiver. Of course, the exigent hams can put a small I2C LCD to have a nice visual feedback.
They are made around a ATMEGA328 and can be programmed with Arduino IDE.
All they need is a small GPS and a transceiver. Of course, the exigent hams can put a small I2C LCD to have a nice visual feedback.
After the Easter Holiday I will put them to work and I'll keep you in touch!
26 aprilie 2016
RFSM2400 and WinLink Winmor
Today I did some tests focused on the file transfer speed using two soundcard modems.
RFSM-2400 is a freeware client program which can transfer files over a radio channel, using MIL-STD-188-110A standard (300Hz to 3.3 kHz-2400 baud).
Winmor TNC, is a donationware program with a modulation scheme that resembles very close with the one used on PACTOR modems. The speed is bandwith related and is adaptive between 200 Hz and 2000 Hz.
RFSM 2400 can't be used to send files to internet servers but the Winmor is widely used with RMS Express to connect to various iGates around the world to send e-mails.
For tests I used a FT-991 connected
to RMS Trimode and to RFSM-8000 (can act as a server) and a IC-7300 connected to the RFSM-2400 and RMS Express with Winmor TNC.
I sent a jpeg file in size of 56.0 KB (57,344 bytes or 448.000 bits) with RFSM-2400 and with RMS Express via Winmor TNC.
The radios were set on 51 MHz, on dummy loads at 5W with a distance of about 1 m between them. Both were on Wide and the signals on S-meter were peaking S3-S5. The modulation was set to not activate the ALC.
The results were astonishing! Via RMS Express, I sent the file in about 20 minutes.
Using RFSM-2400 the same file took less than 4 minutes...
So, the quick and dirty test have some conlusions:
1. When e-mail is important, Winlink + Winmor TNC is the one. There are many iGates on HF and is impossible to miss one, especially if you use the VOACAP tables to estimate the best channel for the given day and hour.
2. Do not try to send big attachements via Winlink! Instead, focus on smaller files, plain text or, if attachements are mandatory, use a good compression software.
3. If ad-hoc networks are the scope, RFSM is the best! You can define a FTP directory and mailboxes for the radio stations and each station can upload emails download their own. The FTP is very usefull for sharing files from one station to another. Good for a regional or national Emergency network.
A plus for RFSM-2400 is the chat and beacon mode!
RFSM-2400 receiving test |
Winmor TNC, is a donationware program with a modulation scheme that resembles very close with the one used on PACTOR modems. The speed is bandwith related and is adaptive between 200 Hz and 2000 Hz.
RFSM 2400 can't be used to send files to internet servers but the Winmor is widely used with RMS Express to connect to various iGates around the world to send e-mails.
For tests I used a FT-991 connected
Winmor TNC receiving test |
to RMS Trimode and to RFSM-8000 (can act as a server) and a IC-7300 connected to the RFSM-2400 and RMS Express with Winmor TNC.
I sent a jpeg file in size of 56.0 KB (57,344 bytes or 448.000 bits) with RFSM-2400 and with RMS Express via Winmor TNC.
The radios were set on 51 MHz, on dummy loads at 5W with a distance of about 1 m between them. Both were on Wide and the signals on S-meter were peaking S3-S5. The modulation was set to not activate the ALC.
The results were astonishing! Via RMS Express, I sent the file in about 20 minutes.
Using RFSM-2400 the same file took less than 4 minutes...
So, the quick and dirty test have some conlusions:
1. When e-mail is important, Winlink + Winmor TNC is the one. There are many iGates on HF and is impossible to miss one, especially if you use the VOACAP tables to estimate the best channel for the given day and hour.
RFSM-2400 receiving private file (mail) |
3. If ad-hoc networks are the scope, RFSM is the best! You can define a FTP directory and mailboxes for the radio stations and each station can upload emails download their own. The FTP is very usefull for sharing files from one station to another. Good for a regional or national Emergency network.
A plus for RFSM-2400 is the chat and beacon mode!
15 aprilie 2016
Playing with the front end of the IC-7300
I heard some rumors about how bad is the IC-7300 front-end and how unsuitable is for hunting low signals so I want to try to push the input to the limits.
So, I put a power splitter to the antenna input of the radio and feed it with two signal generators.
One set on the receiving frequency at -100dbm and one at various frequencies, set at 0dbm. You see, the difference between the signals is huge in terms of input signals...
I am not trying to say that this setup will produce the same result as in real life but is a base for some evaluation of the receiver.
Therefore, the receiving signal is at S1 (-100 dbm) and the perturbation will be at about S9+27 db, according to the IARU reccomandation for HF S-meters.
The radio was set to work with no preamp nor ATT, and the NR OFF.
At S1, the signal was full readable with some noise. With NR ON set at 5, the noise dissapeared and the receiving signal was full quiting the speaker!
When I was applying the perturbation outside the selected filter, OVF quick came on the LCD and the noise increased but the signal was still readable. The NR made the signal nice and clean, altough not so clean as the first time.
When playing with the perturbation signal inside the same filter's passband, the noise increased a little bit but not as I expected.
When the OVF was LIT, there was some artifacts on the waterfall.
The OVF and the artifacts was gone when I reduced the RF gain (instead of 12, the RF gain was set to 10).
The signal was still readable but with a price in noise level... The NR does it's job very well in reducing that noise.
By reducing the perturbation signal at -6 dbm, the OVF goes down and so did the WF artifacts.
At -12dbm, only a slight increase in the noise was there, nothing to upset me, even without the NR.
This beahviour was observed anywhere in the HF bands. I did not test yet the VHF (50+70 MHz).
Indeed, the out of band strong signals are able to put some noise in the receiving band but is not so bad as stated on some other places on the net.
However, the biggest problem is with the harmonics; I set the signal generator at 7.150 kHz at 0 dbm and I found a S9 signal on 14.300 kHz and a S8 on 21.450 kHz! This could be a problem when working on a crowded area (crowd of ham, of course).
A theoretical approach say that the best antenna for this radio will be a monobander or a non-resonant antenna tuned with a AH-4.
As a personal experience, I used the radio with a multiband vertical and find nothing to complain as the nearest ham is at about 8 km from me and there is a hill between us.
The test was long and complicated as I measured also the S/N ratio but nothing spectacular shows... Only the conclusions above.
For this test I used a HP 8656B and a IFR2945A.
73 de Adrian YO3HJV
So, I put a power splitter to the antenna input of the radio and feed it with two signal generators.
One set on the receiving frequency at -100dbm and one at various frequencies, set at 0dbm. You see, the difference between the signals is huge in terms of input signals...
I am not trying to say that this setup will produce the same result as in real life but is a base for some evaluation of the receiver.
Therefore, the receiving signal is at S1 (-100 dbm) and the perturbation will be at about S9+27 db, according to the IARU reccomandation for HF S-meters.
The radio was set to work with no preamp nor ATT, and the NR OFF.
At S1, the signal was full readable with some noise. With NR ON set at 5, the noise dissapeared and the receiving signal was full quiting the speaker!
When I was applying the perturbation outside the selected filter, OVF quick came on the LCD and the noise increased but the signal was still readable. The NR made the signal nice and clean, altough not so clean as the first time.
When playing with the perturbation signal inside the same filter's passband, the noise increased a little bit but not as I expected.
When the OVF was LIT, there was some artifacts on the waterfall.
The OVF and the artifacts was gone when I reduced the RF gain (instead of 12, the RF gain was set to 10).
The signal was still readable but with a price in noise level... The NR does it's job very well in reducing that noise.
By reducing the perturbation signal at -6 dbm, the OVF goes down and so did the WF artifacts.
At -12dbm, only a slight increase in the noise was there, nothing to upset me, even without the NR.
This beahviour was observed anywhere in the HF bands. I did not test yet the VHF (50+70 MHz).
Indeed, the out of band strong signals are able to put some noise in the receiving band but is not so bad as stated on some other places on the net.
However, the biggest problem is with the harmonics; I set the signal generator at 7.150 kHz at 0 dbm and I found a S9 signal on 14.300 kHz and a S8 on 21.450 kHz! This could be a problem when working on a crowded area (crowd of ham, of course).
A theoretical approach say that the best antenna for this radio will be a monobander or a non-resonant antenna tuned with a AH-4.
As a personal experience, I used the radio with a multiband vertical and find nothing to complain as the nearest ham is at about 8 km from me and there is a hill between us.
The test was long and complicated as I measured also the S/N ratio but nothing spectacular shows... Only the conclusions above.
For this test I used a HP 8656B and a IFR2945A.
73 de Adrian YO3HJV
Abonați-vă la:
Postări (Atom)
Most viewed posts in last 30 days
-
Kenwood Programing Software FIRMWARE: KDS-100 504XXXXX 4A46 PTT ID Display feature 176.86 KB CURRENT 401XXXXX F7FC Corrects lock up whe...
-
Icom programming Software GM-110SC rev.1.2. ex1725. IC-3FX 245MHZ THAILAND CB HANDY RADIO, EX2020 REV 1.0. IC-3FGX 80 CHANNELS 245MHZ THAILA...
-
Icom IC-7300 wide band modification by PA2DB: Remove bottom and find the diode matrix (near big chip) Open RX 0.030-74.8Mhz (REMOVE D...