Does anyone have a PCR-1000 ICOM remote controlled receiver?
How long can the serial port cable be? I heard it was operating at something like 112,000 baud and could not be run the 200 feet to our roof. This makes it a deal breaker.
Is there a better all mode all band remote controlled system for roof mount to avoid long cable runs for satellite receiption across all bands..?
Bob
On 2/9/07, Robert Bruninga bruninga@usna.edu wrote:
Does anyone have a PCR-1000 ICOM remote controlled receiver?
How long can the serial port cable be? I heard it was operating at something like 112,000 baud and could not be run the 200 feet to our roof. This makes it a deal breaker.
Was the limitation the RS232 being voltage-based, or was it a timing thing, Bob?
There are commercially-available converters to go from voltage-based "RS" standards to current-based ones if it's just a distance limitation brought on by the low voltages and cable loss.
I would think as long as you could get the signal there and back, since RS232 is asynchronous -- the converters would work.
(But you probably already knew that...)
I just Googled for "RS232 extender" and this comes up, for example: http://www.ramelectronics.net/HTML/EXT-RS232.htm
They don't say, but they're probably just converting from RS232 to RS422 or RS485.
Googling "RS232 to RS422" yields this: http://www.simplycheap.com/videoanalyddconv002.html And it actually says it supports the speed you need.
Those are cheaper. Gotta love anything at a website called "simplycheap"! (GRIN)
Only worry would be timeouts in the application layer of the protocol, and I doubt at your distances it would be a problem. Can you get power up on the roof or nearby enough to power the remote converter unit?
Nate WY0X
Hi Bob,
You can always use an RS-232 to RS-485 converter and go a few thousand feet. If you don't want to build one, lots of companies sell them in the $100-$200 ramge. I think even Radio Shack has them although I don't know the exact specs on theirs.
Here is a company that makes several versions - 115K bps up to 4000':
http://www.bb-elec.com/product_family.asp?FamilyId=15
73, Tony AA2TX
---
At 05:05 PM 2/9/2007, Robert Bruninga wrote:
Does anyone have a PCR-1000 ICOM remote controlled receiver?
How long can the serial port cable be? I heard it was operating at something like 112,000 baud and could not be run the 200 feet to our roof. This makes it a deal breaker.
Is there a better all mode all band remote controlled system for roof mount to avoid long cable runs for satellite receiption across all bands..?
Bob
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
On Feb 10, 2007, at 11:05, Robert Bruninga wrote:
Does anyone have a PCR-1000 ICOM remote controlled receiver?
How long can the serial port cable be? I heard it was operating at something like 112,000 baud and could not be run the 200 feet to our roof. This makes it a deal breaker.
It powers up at 9600 baud. If you use the Icom supplied Windows software, the first thing it does is change to 38400 baud.
The longest cable I've ever tried with mine was just over 20 feet... but I wonder if you couldn't get away with 200 feet especially if you used software that stayed at 9600 baud.
Is there a better all mode all band remote controlled system for roof mount to avoid long cable runs for satellite receiption across all bands..?
Is a computer on the roof a possibility? Given a network connection it could remote control a variety of receivers (including a PCR-1000 or Winradio) and also digitize the audio, making it simpler to get that back down the 200 foot run as well.
73, Jim
Hi All
On Feb 10, 2007, at 11:05, Robert Bruninga wrote:
Does anyone have a PCR-1000 ICOM remote controlled receiver?
How long can the serial port cable be? I heard it was operating at something like 112,000 baud and could not be run the 200 feet to our roof. This makes it a deal breaker.
It powers up at 9600 baud. If you use the Icom supplied Windows software, the first thing it does is change to 38400 baud.
I found this - partial quote follows:
http://www.lammertbies.nl/comm/info/RS-232_specs.html
The standard has a clear answer, the maximum cable length is 50 feet, or the cable length equal to a capacitance of 2500 pF. The latter rule is often forgotten. This means that using a cable with low capacitance allows you to span longer distances without going beyond the limitations of the standard. If for example UTP CAT-5 cable is used with a typical capacitance of 17 pF/ft, the maximum allowed cable length is 147 feet.
The cable length mentioned in the standard allows maximum communication speed to occur. If speed is reduced by a factor 2 or 4, the maximum length increases dramatically. Texas Instruments has done some practical experiments years ago at different baud rates to test the maximum allowed cable lengths. Keep in mind, that the RS232 standard was originally developed for 20 kbps. By halving the maximum communication speed, the allowed cable length increases a factor ten!
cheers
Steve
participants (5)
-
Anthony Monteiro -
Jim Tittsler -
Nate Duehr -
Robert Bruninga -
Steve Fraser