18 iulie 2011

Homemade USB Digimodes Interface

I am a big fan of Digimodes as you maybe know already!
Therefore, I am always in the search of the “perfect” Digi Interface which also has to allow me to control the radio via Ham Radio Deluxe, one of the best of it’s kind…
I already have a RiGExpert Standard interface but this is assigned to a Kenwood TS2000 radio at YO3KSR, our club station and this made a big “gap” in my shack.
My “ideal” interface has to be wired to a PC only with one cable.
I want to have a “hardline” PTT and a Carrier Detect (for Echolink use) and a CAT port.
Of course, a sounboard because want to be able to use the interface with some digital voice software which requires two sound boards (one in the laptop).
I made a lot of interfaces in the past; most of them was “the simple” type; only providing isolation between PC and transceiver with two little transformers and a optocoupler for PTT but these ones required a external USB2COM adapter and a lot of wires…
So, my “dream” was still in the “cloud”.

A few days ago, while I was inspecting the junk box, I found a lot of unused “components”…
A USB sound card from Behringer (UC202), some USB2COM adapters and a very little USB hub…
Hmmm… I wonder if I can use those to homebrew a nice versatile Digimodes interface!
I often see fellow hams that build things from scrap! I admire them because this need a lot of time and commitement! I have the last "thing" but I don't have the time so, I think I do not "cheat" by using demo boards or some finished "scrap" in my junk box.

Here is the plan (click to see the "big pictures"):

I choose a USB 2.0 HUB with four outputs as a simple math will show that we need 3 of them in our setup and we can use one for further "developments".
A short trip to a local DIY store provided all the necessary components; the case, the board and some LED’s because I didn’t have the green ones!

I agree with “one picture made a thousand words”, therefore I let you see what is the result.
So, I made a "motherboard" where I put the USB plug, the LED's, and the I/O volume potentiometers. There is some pads left for external DC input regulation with a 7805 circuit (not populated yet) and for isolation transformers (in the eventuality of 50 Hz hum).
I also provided some common ground because I choose not to use isolation. Hmmm, the "isolation" story seems to be a humbug of sime sort because, from what I seen in the market, the CAT port is not isolated so, despite the isolation of the audio and PTT, the PC IS connected to the transceiver! So, why try to complicate my life?
In the upper

The audio USB board UCA-202 from Behringer:
This board has a Stereo Line input and a Stereo Line Output. There is also a "monitor" headphones output, but this is not used. Maybe I will put a little speaker inside the box but is not yet necessary!
The USB2COM adapters:

The USB2COM adapters was tested before te see how they works!

If you can see them here it's a proof that they passed the test, HI!
Like I said, I used one for CAT control. This one was left "in one piece" to provide some mechanical fixing. The one for PTT and CD (Carrier Detect - Open Squelch) was removed from the DB9 connector. This was necessary because all the signals (including Audio I/O) will be sent to the transceiver via one cable).
The PTT was set on COM's RTS and the CD on the COM'S CD (to be clear, HI). Here I use two K817 optocouplers. The PTT port can whitstand about 50 mA at 70V.

The LEDs

I like to have some visual information about the working state of the interface, so I desoldered the original LED from every board and reroute them on the front panel.

From left to right:

-Blue: Power on USB HUB;

-Green: Power on CAT COM1;

-Green: Audio Board recognised by the OS;

-Red: PTT on COM2

-Yellow: CD on COM2.

-Blue: not connected.

The "look":

After closing the case, the HM Interface looked fantastic, especially in the dim light!
On the rear panel, I provided 3 RCA for Audio I/O and for PTT/ They are not wired yet.

Further development may include a second USB audio board for digital voice...

OK, it is not perfect, but the tests showed that this "box" performs well... I have only one complain: the Input level is often too small for the sound board. Despite this, the excellent S/N ratio of the Behringer board made me think twice before adding a small input preamplifier!
The two potentiometers are unused...
The cost is much under a commercial interface... Much!

And, for the final, what will be a CAT-Digimodes interface without a Tom-CAT?

73 de YO3HJV


I added a small preamplifier (around 6 db) on the audio input of the interface. The signal goes into one of the two potentiometers (reserved on the motherboard) to fine tune the input volume. A small Switch on the front panel allow me to bypass the preamplifier because the signal from ICOM IC7000 is loud enough to drive irectly the soundboard.
I also put a 4 GB flash memory for various purposes (the HRD Logbook, audio recording of my QSO's and a small collection of digimodes software-around 300 Mb).

Asa nu!

Acum cateva seri testam o interfata pentru moduri digitale si am ajuns in banda de 20m unde, am avut placuta surpriza sa intalnesc o statie YO, YO3FOP care chema in PSK31.
Imediat i-am raspuns, bucurandu-ma ca voi avea posibilitatea de a schimba cateva cuvinte cu un "vecin".
Iata cum a decurs "dialogul":

02:54:04> Main
YO3FOP de YO3HJV YO3HJV pse kn

Your Call de YO3FOP

nu ati incarcat in program indicativul si statia chemata nu stie cui faceti apelul
Buna dimineata.
Numele Adrian, QTH Bucuresti.
Semnalul este f puternic, merge OK.
Eu tocmai am terminat si testez, o interfata pe USB pentru moduri digitale, care are placa de sunet, com pentru CAT samd..

Hi OM,
Report : 599 599
Name : ILIE ILIE qth BUCHAREST BUCHAREST loc KN34CK [90.0° 6.6km] KN34CK
Member EPC #2937 ROØ5
Info : QRZ.COM
How copy? BTU OM, YO3HJV de YO3FOP pse kn

Copiez f bine, dupa cum am spus, doar ca speram sa vb cu un om, nu cu un calculator...
Multam de legatura, succes si mny DX
YO3FOP de YO3HJV YO3HJV pse kn

YO3HJV de YO3FOP 73 OM and thanks for this BPSK-31 QSO on 2Øm, good DX in 2Ø11.

Trecem de faza I, in care dl. YO3FOP nu a introdus indicativul in MACRO-urile din HRD (cel putin asa suna predefinitele din DM780 si ajungem la adevarata problema:
Dezinteresul operatorului uman pentru realizarea unei legaturi!
Imi pare ca, folosind exclusiv mesajele predefinite devenim, cumva, sclavii calculatoarelor, negandu-ne tocmai placerea acestui hobby: comunicarea si puntile intre oameni!

Modurile digitale sunt un mijloc de realizare a legaturii si nu un scop in sine; se pare ca am uitat de asta! Este de inteles asa ceva intr-un concurs sau intr-un pile-up atunci cand timpul corespondentului este pretios. In rest, folositi comenzile "macro" cu parcimonie; nu este deloc greu sa adaugi cateva cuvinte, chiar daca tastatura QWERTY nu iti este cel mai bun prieten!
Am intalnit deseori corespondenti cu care am purtat conversatii in moduri digitale. Tocmai acestia au fost motivul pentru care acum sunt atat de atras de ele iar unii chiar mi-au spus ca evita sa intre in dialog cu statiile care shimba doar controalele de rigoare. Adica exact cum puteti observa in "dialogul" de mai sus!
Incercati sa evitati acest tip de legatura! Asa nu!

73 de yo3hjv

12 iulie 2011

RadioMagazinYO Nr.9-10 iulie-august 2011

A aparut RadioMagazinYO, numarul de vara, comun pentru lunile iulie si august 2011!
Din cuprins:
-Friedrichshafen Ham Fair 2011 de YO3HJV;
-O noua amenintare pentru comunicatiile HF de 4X1AD;
-Webinare pentru radioamatori de 4X1AD;
-Radiocomunicatii libere: CB & PMR 446 de YO3FTI;
-Transfer de date via HF de YO3FTI.

Revista verii 2011 vine cu un numar mai mare de pagini. In continuare ea este disponibila si in forma tiparita pentru abonati.
Premiul pentru acest numar este o statie radio mobila VHF, oferita de MATRA SYSTEMS.
Incepand cu acest numar, revenim la necesitatea autentificarii folosind contul deschis pe site-ul radioclubului pentru descarcarea revistei RadioMagazinYO.
Dupa logarea pe site, veti avea acces la link-ul pentru descarcarea revistei in format electronic.
Puteti descarca Revista RadioMagazinYO aici

02 iulie 2011

9k6 APRS with Ui-View and TM-D710

LATER EDIT: You can use the same settings for the Kenwood TH-72 because the TNC chipset is the same. Tested and work OK!

Last days I was confronted with a big problem!
How to establish a APRS local gateway from Internet to Radio with a TM-D710 and UI-View, the well known software from G4IDE!
First time, I started the Kenwood TM-D710 in Packet mode and I made the necessary settings for 9k6 but when it connects to UI-View, the baudrate reverted to 1k2!

The main issue is that this software have more than 7 years of no-upgrade due to the SK of the author and the INIT file for the Kenwood TM-D710 radio is not included within the CMD files.
Therefore I start to look around how the software sent the commands to the radio.
It seems that in the CMD folder within the installation directory is the key.
Inside this folder, there are some files that define the initialisation commands for every TNC listed in UI-View menu and that initialisation occured everytime I tried to setup the communications with the radio.
The solution is here:But how we find the TM-D710-9k6 TNC-type?
Very simple!
We search in the CMD folder for a file named "TM-D700.ORG".
Open it with Notepad. You should see something like this:

;This is a copy of the default version of TM-D700.CMD.
This is a sample TNC initialisation file for use with
;the Kenwood TM-D700.
;DON'T alter anything in this section unless you are

;sure you know what you are doing!




^C AI 1!AI 1
Now, open a new file in the Notepad and paste the following code:
;DON'T alter anything in this section unless you are
;sure you know what you are doing!

;Control mode on.
TC 1!TS 1
;Select TNC PKT mode on A band.
TN 2,0!TN 2,0
;Waiting for command prompt.
;Repeating the first two commands is not an error!
; Below we can set the beacon in 10*N seconds. 60 means 600 seconds
; You can set the beacon text with BTEXT ...
; You can set the Digipeating function but have to add some other commands
;Below we setup the RF TNC baudrate

;If you want 1k2 baud, simply replace "9600" with "1200"
HBAUD 9600

TC 1
TN 0,0

After that, rename the .txt file into "TM-D710-9k6.CMD" and save it in the same CMD folder.

Open UI-View, go to SETUP menu, click on COMMS SETUP and, BINGO, you will have the new TNC option enabled!

Watch the first picture again, make the same settings and go for 9k6 APRS with the Kenwood TM-D710!
Beware: you have to keep the radio with no menu-enabled TNC! The TNC will "revive" once you hit the "OK" button (first image) and the LCD on the radio will show "PACKET96"!

73 de YO3HJV

I was asked by Jack, G4AMF to tell him how to setup the radio for 1200 baud APRS operation.
If you look on the code above, you will see a "commented" line (with ; in the beggining) whic tells you how to do it.
You simply replace 
HBAUD 9600 with HBAUD 1200
and, Voila! you got the 1k2 APRS working with TMD 710 as KISS  TNC! 
Don't forget to put the radio in TNC mode and not in APRS mode!
The same 73 from Romania!

Arhivă blog

OnLine logbook YO3HJV

Ham News