USB extender via cat5/6

Status
Not open for further replies.

millam

Old Radio Guy
Premium Subscriber
Joined
Jan 18, 2005
Messages
656
I bought this hoping to be able to get my sdr's closer to the antennas. I bought it on ebay.
U2EX50, AV Access company. It works laying on the floor next to my computer. 4 usb-2 sockets.
$50 bucks, ebay has a used 1 for $24. The only problem is that it needs 12 volts at the transmitting
end. Wall wart supplied. 165 feet with cat5. Just telling about this no guarantee it will work for you.

Mil

Oh I had SDR# with a Airspy and HDSDR with a Airspy on running on it.
 

krokus

Member
Premium Subscriber
Joined
Jun 9, 2006
Messages
5,964
Location
Southeastern Michigan
I bought this hoping to be able to get my sdr's closer to the antennas. I bought it on ebay.
U2EX50, AV Access company. It works laying on the floor next to my computer. 4 usb-2 sockets.
$50 bucks, ebay has a used 1 for $24. The only problem is that it needs 12 volts at the transmitting
end. Wall wart supplied. 165 feet with cat5. Just telling about this no guarantee it will work for you.

Mil

Oh I had SDR# with a Airspy and HDSDR with a Airspy on running on it.
That looks interesting. I wonder if a POE, or DC injector, could be used for the remote end?

Sent using Tapatalk
 

kruser

Active Member
Premium Subscriber
Joined
Nov 25, 2007
Messages
4,987
Location
West St Louis County, MO
I bought this hoping to be able to get my sdr's closer to the antennas. I bought it on ebay.
U2EX50, AV Access company. It works laying on the floor next to my computer. 4 usb-2 sockets.
$50 bucks, ebay has a used 1 for $24. The only problem is that it needs 12 volts at the transmitting
end. Wall wart supplied. 165 feet with cat5. Just telling about this no guarantee it will work for you.

Mil

Oh I had SDR# with a Airspy and HDSDR with a Airspy on running on it.

This one you mentioned does work.
I've also used "active" USB only extenders that were 54' long each. I think they were Tripp-Lite models. You could daisy chain three together which I did for a total length of 164 feet. They also worked but I never tried putting a multi-port USB hub on the end to run more than one RTL-SDR dongle hooked up at the far end. The one dongle I did need at the antenna worked great though and has been installed for about three years now with zero connection issues. I did coax seal all the exterior USB extender connection points except the dongle end itself which is all mounted in an inverted sealed PVC pipe so I can swap it or the antenna easily.
The model you mentioned I also only tried it laying on the floor and never for a real world test but I did not see why it would not work.
 
Last edited:

kruser

Active Member
Premium Subscriber
Joined
Nov 25, 2007
Messages
4,987
Location
West St Louis County, MO
That looks interesting. I wonder if a POE, or DC injector, could be used for the remote end?

Curious as to why you would need POE or power injection at the far end? POE or power injection is always used at the source of close end as that's where power is available.

I bet that's exactly what the 12 VDC adapter at the indoor end is doing, regulating the 12 volts back down to 5 volts at the device end for voltage loss correction at the far end. Basically a lower voltage method of POE. True POE basically does the same but inserts 48 VDC or more at the power supply end and then regulates that back down to the device voltage. This overcomes voltage loss rather well in most cases using standard ethernet cable.

I think the Tripp Lite extenders I use simply use a larger gauge wire size to keep voltage loss at a minimum but I bet they would not work with a passive non-powered hub running several devices that need any appreciable amount of current.
This extender using Cat5 the OP mentions sounds like it may be a better solution if you do have power hungry devices at the far end.
 
Last edited:

millam

Old Radio Guy
Premium Subscriber
Joined
Jan 18, 2005
Messages
656
kruser, I did not say there was a 12VDC adapter at the indoor end! The power supply is on the antenna end.
I have a Monoprice usb extender that is around 150 +/-feet with 1 amp in the middle. Haven't tried it with a hub
though. It works great but would require a big hole through the wall.
 

kruser

Active Member
Premium Subscriber
Joined
Nov 25, 2007
Messages
4,987
Location
West St Louis County, MO
kruser, I did not say there was a 12VDC adapter at the indoor end! The power supply is on the antenna end.
I have a Monoprice usb extender that is around 150 +/-feet with 1 amp in the middle. Haven't tried it with a hub
though. It works great but would require a big hole through the wall.

Sorry, I took it as you meant the 12VDC adapter was at the indoor end. That seems the logical place to put it so you can regulate back down to 5VDC at the outdoor end which is what USB needs.
Probably something in the USB spec that does not allow what I'm thinking.
After reading the specs at their website, it looks like the 12VDC adapter is basically used to power the four port hub at the outdoor end.
They probably also use the adapter to power the active USB data signal amplifiers in the cable where the Tripp Lite models I'm using get their power from the computer end through the USB cable itself. This is what gives them the "Active" classification instead of Passive.
I still find it odd that both type devices have the same distance specs though. Something else must limit that distance spec. Possibly the amplifiers used for the data signals. Each one added adds a USB device or hub device in device manager.

So, your device not only needs the special USB extender run to the antenna but also a power source to power the wall wart. That kinda sucks.
I wonder if you could use any ordinary power injector at the indoor end and an power extractor at the antenna end using existing coax for the power feed? That would eliminate the need to have 120 volts AC for the wall wart at the antenna end as long as you feed 12 VDC up the coax at a slightly greater current capacity than the included adapter.
Or like krokus said, a standard POE setup to supply power out to the transmitter (Hub end). That would be the better way to go as long as you had a device at the outdoor end to breakout the 48VDC POE voltage and reduce it back down to regulated 12 VDC with a cable to plug into the Transmitter as they call it. The term Transmitter did confuse me when used with USB as USB is actually two way or duplex so signals can flow both directions. Some isochronous (or is it isosynchronous?) devices may rely upon a special transmitter (hub) end though. Like their mention of cameras but I think that is more a bandwidth thing more than anything.
 
Last edited:

millam

Old Radio Guy
Premium Subscriber
Joined
Jan 18, 2005
Messages
656
"use the adapter to power the active USB data signal amplifiers in the cable" What does this mean?
The cable is "CAT5" ethernet not a usb cable. There are no "AMPLIFIERS" in the cable. I'm using a
50 foot cat5 cable from ebay. NO AMPLIFIERS.
 

kruser

Active Member
Premium Subscriber
Joined
Nov 25, 2007
Messages
4,987
Location
West St Louis County, MO
"use the adapter to power the active USB data signal amplifiers in the cable" What does this mean?
The cable is "CAT5" ethernet not a usb cable. There are no "AMPLIFIERS" in the cable. I'm using a
50 foot cat5 cable from ebay. NO AMPLIFIERS.

I could have took it wrong but on that products Support tab for the extender on the manufacturers page, they did mention an amplifier. Not in the PDF manual though.
Just under the Support tab info it says:

"The USB 2.0 extender is considered an active repeater, using a small power supply to amplify the USB signal and preserve the integrity of the data overlong distances."

I took that as meaning the device does have some type of amplifier in it. The function of this amplifier could be the same as those used in USB type extenders like the Tripp Lite model.
Who knows though if the U2EX50 has an amplifier at each end and on both data wires and if the mentioned amplifier is even on the USB signals on the USB side of things or on the wires that carry the USB data but on the ethernet cable side of things.
Any amplifier would be INSIDE the housings at one end or both, NOT in the ethernet cables of course!

They also claim No Drivers but everything I've seen does add a USB Hub to the device list regardless if it is Win, Mac or Linux OS. This is a built in driver for all OSs of course so the claim of no driver should be taken for what it really means that "no additional drivers" are needed. AV Access does state this fact in another one of their support pages.

Either way, it's an interesting device and I could see a use for it with its four port hub at the far end.
I must wonder if they are really converting USB to Ethernet or simply using the 4 pairs available in the spec'd ethernet cables to maintain voltage and signaling and then still using amplifiers like the pure USB extenders use.
The four port hub would still be powered by the included wall wart knowing you can't get 500mA of power at all four ports over that distance when using a single USB port as the source port on a computer.
I'm not knocking the U2EX50 device as like I said, I could find it useful! At the same time, it would be interesting to see inside close up photos of the electronics used in each end.
If chip numbers are legible on both ends, that would tell if it really converts to ethernet or not. If it does convert to ethernet, I wonder why the distance limitation is the same for true USB type extenders.

It sure is a lot cheaper than buying three of the Tripp Lite models to achieve the same distance.
I don't remember for sure but I think just one of the Tripp Lite extenders cost near what the U2EX50 costs and you need three of the Tripp Lite models to equal the same distance! My only Tripp Lite cable end that has the part number and is not sealed is on the roof so no idea on a part number.
 

millam

Old Radio Guy
Premium Subscriber
Joined
Jan 18, 2005
Messages
656
Looking at specs for cat5, 100 meters /317 feet. Reading the description of these devices, sends USB "SIGNAL" 50
meters /165 feet over catX cable. So no conversion, unshielded twisted pair cable can send usb signals better than
straight usb cable? Thats why the usb extender cables have an amp in the middle, right?
 

Attachments

  • ant extender1.pdf
    37.2 KB · Views: 7

krokus

Member
Premium Subscriber
Joined
Jun 9, 2006
Messages
5,964
Location
Southeastern Michigan
Curious as to why you would need POE or power injection at the far end? POE or power injection is always used at the source of close end as that's where power is available.

I bet that's exactly what the 12 VDC adapter at the indoor end is doing, regulating the 12 volts back down to 5 volts at the device end for voltage loss correction at the far end. Basically a lower voltage method of POE. True POE basically does the same but inserts 48 VDC or more at the power supply end and then regulates that back down to the device voltage. This overcomes voltage loss rather well in most cases using standard ethernet cable.

I think the Tripp Lite extenders I use simply use a larger gauge wire size to keep voltage loss at a minimum but I bet they would not work with a passive non-powered hub running several devices that need any appreciable amount of current.
This extender using Cat5 the OP mentions sounds like it may be a better solution if you do have power hungry devices at the far end.

I was a bit ambiguous; I meant an injection at the computer end, to supply power to the remote side. In my case, it would be an interesting way to put two SDR sticks outside, with an enclosure, and only needing one Cat6 cable for the whole setup.

Sent using Tapatalk
 

millam

Old Radio Guy
Premium Subscriber
Joined
Jan 18, 2005
Messages
656
Krokus the design of a POE device was on my mind. I was looking on ebay for the parts to
build one. I googled POE Ethernet and there they were. On ebay looks like hundreds. That tells
you how long I have been out of the Lan business. I'll open up the extender boxes and see what
pins are used and compare them with POE standard if there are any. I'll get back to you on this.
Did you look at the pdf of my setup? I forgot to add my ADSB antenna to the diagram. So I've got
two Airspy's and one RTLSDR running on this extender and it looks normal. That removes about 50
feet of lossy coax.

Mil

Gone for the weekend, GOD bless the USA and its protectors!!!!
 

kruser

Active Member
Premium Subscriber
Joined
Nov 25, 2007
Messages
4,987
Location
West St Louis County, MO
I'll open up the extender boxes and see what
pins are used and compare them with POE standard if there are any.

Take some pics if you do open them up! I'm really curious if they are really converting to true Ethernet over UTP or simply using UTP cables as USB in this case going by the fact a Cat5e or better cable can double up the wires into four pairs using standard 8 conductor ethernet cable.
I've never personally tried sending USB signals over an ethernet cable but it would be interesting to see if it can work.
 
Last edited:

millam

Old Radio Guy
Premium Subscriber
Joined
Jan 18, 2005
Messages
656
Got the POE's that I ordered from ebay (cheap ones). Looks like they are wired as per T568A/B and
they only used 4 wires, 1 2 3 & 6. Won't work with this extender, have to make or modify your cat-X.

Mil
 

hamradionl

Member
Joined
Mar 23, 2014
Messages
730
For those live in Europe, i have tested this unit with RTLSDR and Airspy using 10 meter and seem working. Later this week i test over 30 meters.
Only USB 2.0 and this company use 24 Volt 0.5 Amps AC/DC Power adapter. When work i replace this for 24 Volt 1 Amp to put 2 or 3 RTLSDR in top of mast and using a Hirschmann CATV antenna coupler to connect to 1 antenna.
Why test?
I like to know if this give better SNR instead using 30/40 meter of Coax cable.
LogiLink :: Produkt USB 2.0 Cat.5 Extender bis zu 50m mit 1 Port, PoE|02.06.2019
LogiLink :: Produkt USB 2.0 Cat.5 Extender bis zu 50m mit 4 Port Hub, PoE|02.06.2019
 
Status
Not open for further replies.
Top