Topics

Serial cable to usb dongle to usb cable


Owen Vinall
 

Hi Christopher, 
Re Serial cable length.
Typical I. T. Answer I'm afraid.
Given decent cable terminated correctly and decent Line driver chips 100's of metres but the higher the baud rate or speed the shorter the distance. I believe the line driver chips/ interface in Arduino's were not designed for distance. I have plenty of info and suggestions but to keep it simple what distances are you aiming for ? Part of my job was squeezing the longest distance possible for Comms eg Rs232 on Copper via Radio links Fibre etc etc.

On Wed, 2 Sep 2020, 12:51 am Christopher Miller, <djmalak2k6@...> wrote:
Does anyone know the maximum reach of a serial cable and usb cables?

I have a pc across my bedroom and between my serial dongle and radio I would like to start getting digital modes going. Sorry for the basic questions.

KF4FTR


Christopher Miller
 

It’s ok the pc is now in my shack. It’s honestly the “right” way to solve the issue. I can’t log qsos sitting 20 feet from the radio. I’m just frustrated so ignore me.

On Tue, Sep 1, 2020 at 10:15 AM Gary Anderson <gary.ag5tx@...> wrote:
After reading my post,  I wasn't too clear on 'adding' an active extension cable.
for USB 2.0 :
Computer <-> 16ft Active extension cable <-> 16ft cable <-> dongle

Rgds,
Gary








Christopher Miller
 

I spoke with my wife and I decided it’s easier to just move my desk and swap it with my pc so my desk is next to the radio so I can keep a log and I don’t have to deal with this issue. I’m just tired of moving things around. I furnished our living room last Friday and set up new smart bulbs which was a pain. 

Chris 


Gary Anderson
 

After reading my post,  I wasn't too clear on 'adding' an active extension cable.
for USB 2.0 :
Computer <-> 16ft Active extension cable <-> 16ft cable <-> dongle

Rgds,
Gary


Gary Anderson
 

With quality cable for USB,
USB 2.0 5 meters (~16 ft as Rick said)
USB 3.0 3 meters
You can add an active (repeater) extension cable.  I use these often when I need to extend point to point USB communications.  This might be a solution for you.
The other option is to use a USB hub.  e.g. for USB 2.0 :
Computer <-> 16ft cable <-> USB hub <-> 16ft cable <-> dongle

Serial is too generic of a statement.  Need to know baud/data rate as well as physical interface (voltage levels and single ended vs differential)

Rgds,
Gary


Christopher Miller
 

Hmmm this sucks. I may have to move my radios. Even if I put a bitx on my desk I will need to run coax probably 20 feet. Apartments suck for ham radio.

On Tue, Sep 1, 2020 at 8:44 AM Rick Green <rtg@...> wrote:
On Tue, 1 Sep 2020, Christopher Miller wrote:



> Does anyone know the maximum reach of a serial cable and usb cables?

> I have a pc across my bedroom and between my serial dongle and radio I would like to start getting digital modes going. Sorry for the basic questions.

In general, the max spec for a USB cable is 16 feet.  I don't remember the RS232

spec length, but it would certainly depend on the driver chip. full +-12v will

certainly go farther than +5-0 TTL shortcuts.





--

Rick Green  N8BJX





We, the People of the United States of America, reject the U.S. Supreme Court's

  Citizens United ruling, and move to amend our Constitution to firmly establish

  that money is not speech, and that human beings, not corporations, are persons

                        entitled to constitutional rights.



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Evan Hand
 

Christopher,
Rick is correct, the USB specification is 5 meters or about 16 feet.  Amazon does sell a 20 ft extension cable, with good reviews:
https://www.amazon.com/Extension-Tanbin-Extender-Keyboard-Loudspeaker/dp/B07CBYVQJP

RS232 does not have a specific length specification, however, when using cat 5 cables, 50 feet at 9600 baud is reliable.  

I would be more concerned with the RF feedback and the audio quality of the long audio cable runs.  That is assuming that you will be using the USB just for the CAT control and running the audio signals separately.  If you are also going to remote the USB audio interface, then you are back to the 15 ft limit of USB.  I do not know of a way to convert the USB audio to RS232.  The 48kbit audio sampling would be hard to do with RS232.

One last comment, if you go the USB route (which is what I would suggest), then I would remote the Audio USB dongle and put ferrites on the USB cable to minimize RF interference.  You would also need a powered USB hub for the end closest to the uBITX.  One for the audio dongle and one for the uBITX CAT control.

Above are my recommendations.  Others may have better ideas.  Do the research on the internet and use it at your own risk.  Internet searches can be a friend if you validate the results.
73
Evan
AC9TU


Rick Green
 

On Tue, 1 Sep 2020, Christopher Miller wrote:

Does anyone know the maximum reach of a serial cable and usb cables?
I have a pc across my bedroom and between my serial dongle and radio I would like to start getting digital modes going. Sorry for the basic questions.
In general, the max spec for a USB cable is 16 feet. I don't remember the RS232 spec length, but it would certainly depend on the driver chip. full +-12v will certainly go farther than +5-0 TTL shortcuts.


--
Rick Green N8BJX


We, the People of the United States of America, reject the U.S. Supreme Court's
Citizens United ruling, and move to amend our Constitution to firmly establish
that money is not speech, and that human beings, not corporations, are persons
entitled to constitutional rights.

http://www.MoveToAmend.org


Christopher Miller
 

Does anyone know the maximum reach of a serial cable and usb cables?

I have a pc across my bedroom and between my serial dongle and radio I would like to start getting digital modes going. Sorry for the basic questions.

KF4FTR