Strange behaviour with wireless N adapter and corner reflector antenna

Bought a Mini 150Mbps USB WiFi Wireless Adapter 150M USB LAN Card 802.11n/g/b with 2 dBI Antenna.

This uses the Realtek RT5370 chipset.

I already was using an RT8187L USB with antenna in the back room and I swapped over to the new USB adapter to see how it performed in comparison.

I must say the performance was very impressive, equal to or even slightly more sensitive than the previous Realtek.

So I then played around trying various antennas on the new adapter - dipol, yagi, biquad, patch etc and all performed as per expectations until I attached my corner reflector (dipole based).

Performance was shot to pieces. Signal strength was excellent but quality was almost zero.

I double checked the connection. It's using "G" as I don't have an "N" router.

Is this some sort of modulation issue ?

Any idea Why the huge drop in performance ?

Rob

Ps here's the unit, which at $5 AU is amazing value. Quite well made too.

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Reply to
Dr Who
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with 2 dBI Antenna.

over to the new USB adapter to see how it performed in comparison.

sensitive than the previous Realtek.

yagi, biquad, patch etc and all performed as per expectations until I attached my corner reflector (dipole based).

almost zero.

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OOOps I just realized I put the readings back to front for the corner reflector.

The link quality is excellent at 95%, but the signal strength is terrible.

Changed the connector but still unusable.

All the other antennas work excellently with the adapter.

Reply to
Dr Who

(snip)

yagi, biquad, patch etc and all performed as per expectations until I attached my corner reflector (dipole based).

almost zero.

Faulty antenna - design or fabrication.

Reply to
who where

Tiny little thing. Impressive.

I think you mean signal strength was lousy while link quality was high. The way it works is that link quality is really a measure of the bit error rate. If there's little data moving, the link quality tends to be a rather high number.

Also, some drivers and chipsets seem to have problems reporting the signal strength and quality. I'm not sure of the issue, but I have a USB dongle (chipset unknown) which reports zero signal strength at all times. However, it works just fine.

Good. That makes troublshooting less complicated. However, if your driver allows you to turn OFF the "N" features, I would try that just to see if it helps.

Tell me about the corner reflector. How is the antenna positioned? What is the antenna orientation relative to the reflector? What OS are you using? What program are you using to display the signal strength and quality? Duz it work normally without the corner reflector?

Want me to recycle my previous rant on why using an omni to illuminate a dish (or corner reflector) results in plenty of receive gain, and miserable transmit gain?

Probably not.

Nope, not enough info. (Hint: Numbers please).

I'm tempted to buy one just to play with it. Looks nice on paper.

Reply to
Jeff Liebermann

The RT5370 is a RAlink part, not realtek. Different companies.

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Both companies have their fans. However, I can tell you the RT8187 is totally kick ass. The Rokland Tube/U version is worth checking out, unless you are looking for uber cheap parts.

This is the high speed alfa I have

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The website indicates Ralink RT2770 RT2750. I don't recall which chip set it uses. I can tell you the 2.4Ghz performance is no comparison to the RT8187, though it is fine for home use. Just don't expect to do any long distance links with the Ralink part.

The RT8187 has a virtual router option in the windows driver. Very nice.

Reply to
miso

kick ass. The Rokland Tube/U version is worth checking out, unless you are looking for uber cheap parts.

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uses. I can tell you the 2.4Ghz performance is no comparison to the RT8187, though it is fine for home use. Just don't expect to do any long distance links with the Ralink part.

Yes, I've use the 8187L chipset for many years and I'm well aware of how good a performer it is.

This RT5370 chip is no slouch either and it's low power use as well, which is a good thing given the 8187L pulls full USB power and drains the battery quicker than most.

I think Jeff may be on the money that it's not reporting correctly. Same thing happens with Realek adapters in Linux where they look bad but are actually going OK.

For $5 - 6 it's an ammazingly good little dongle.

I will try a few file transfers and clock it to see what happens.

Reply to
Dr Who

If you read the reports from Rokland, Data Alliance, etc. the RL8187 is an exceptional chipset. Both advise that you get the RL81817 if you don't want 5GHZ. I have them both and can tell you the Realtek runs rings around the RAlink.

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if you need N, get the 036NH, otherwise get the 036H.

My experience isn't simply with reporting, but rather with actual long distance use. Based on simply the number of WAPs seen, the 8187 is the winner as well.

Sure it is fine for the price. Search for "300Mbps USB Wireless Adapter WiFi Lan Network Card". Three bucks more, but the realtek chipset.

I prefer the realtek driver over ralink.

Reply to
miso

exceptional chipset. Both advise that you get the RL81817 if you don't want

5GHZ. I have them both and can tell you the Realtek runs rings around the RAlink.

distance use. Based on simply the number of WAPs seen, the 8187 is the winner as well.

Lan Network Card". Three bucks more, but the realtek chipset.

Interesting stuff miso.

I've long been a fan/user of the 8187L and yes it is top of the 54G heap - and the current long distance heap I suppose.

I just ran some basic tests to compare throughput and sensitivity of the 8187L v the cheap RT5370.

Sent a 9 MB file between my DLink DSl-2642B router (standard dipole) and my old

1.6 Athlon test rig several rooms away. Distance about 30 feet, three red brick walls between antennas.

15 element beam yagi - 8187L - 6.2 secs, 5370 - same

10 DBI Biquad - same results as above.

So no variation in throughput.

1.45 MB/sec is pretty good in that situation.

Ran Network Stumbler and used beam yagi to pick up weak signal with 8187L more than 100 metres away - 77 dBm

Hooked up the 5370 to yagi, wasn't in the same ball park for signal strength, way down near 95 dBm

So 8187L is king on sensitivity.

BUT, the interesting thing was that whereas the 8187L picked up 6 ssids, the

5370 found 7.

The yagi was not moved between testing.

While the 8187L is clearly the better chipset, for $6 the 5370 is pretty amazing value for in house use.

Rob

Reply to
Dr Who

exceptional chipset. Both advise that you get the RL81817 if you don't want

5GHZ. I have them both and can tell you the Realtek runs rings around the RAlink.

distance use. Based on simply the number of WAPs seen, the 8187 is the winner as well.

Lan Network Card". Three bucks more, but the realtek chipset.

the current long distance heap I suppose.

v the cheap RT5370.

old 1.6 Athlon test rig several rooms away. Distance about 30 feet, three red brick walls between antennas.

than 100 metres away - 77 dBm

way down near 95 dBm

5370 found 7.

amazing value for in house use.

Oh forgot to say, looks like my corner reflector is on the blink/ Must be a bad connection somewhere - was working great but now not.

So it's nothing to do with the adapters.

Interesting stuff though.

Rob

Reply to
Dr Who

I bought ed Alfalink awus036h for my Satellite receiver NeoSat 9900hd Spe ctra Plus but Alfa Link do not work with satellite receiver. Later i check receiver compatible with only RAlink RT 5370 chip dongle only. I want to as k is it possible my AlfaLink awus036h chnage firmware or install Ralink chi p software.

Reply to
muhammadnaveedsaeed

Well the US is for the USA. Are you in the USA?

Reply to
miso

I'm confused - What are you trying to do ? After connecting a WiFi adapter to the Sat Receiver - what do you expect to happen ?

What is the topic "Strange behaviour with wireless N adapter and corner reflector antenna"

Sat receiver -->

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WiFi adapter -->

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WiFi dongle -->

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Reply to
ps56k

it would appear - that by adding an Internet connection to the Sat Receiver box, you can then pull & display certain info from the Internet.... ie - weather.

SO - by adding a USB type WiFi adapter to your Sat Receiver, and having a local WiFi network avail, you can view info from the Internet.

Not sure what the big deal is - just add the suggested WiFi adapter unless the issue is - too far away from your WiFi access point ??

Still not sure where the "corner reflector antenna" comes into the discussion ??

Sat receiver -->

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WiFi 5db adapter -->

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WiFi RT dongle -->

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Reply to
ps56k

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