home 
wiki
wiki
DickSmithAmplifier
A little while back there was a heads-up and ensuing discussion on the Melbourne Wireless mailing list about a 500mW 802.11b/g amplifier that Dick Smith New Zealand sells. Well I bought one. This is the item in question:
http://www.dse.co.nz/cgi-bin/dse.storefront/406579bb02b2526c273fc0a87f990748/Product/View/XH6825
I ordered it in early February and received a customer code from the website but no email confirmation. After a month I just assumed that the order didn't go through. Then on 10th March it arrived. The invoice is interesting as it appears I haven't been charged NZ GST on the item, even though the "tax code" says that I have. I paid NZ$264 for it, which is AUS$240. I also bought a 7dBi magnetic mount antenna (which I now strongly suspect to be a 5dBi antenna) for NZ$40.89 and postage was NZ$25.11. The grand total was AUS$298 charged to my credit card.
The Amp has a RP-SMA connector on the antenna side and a standard-SMA connector on the radio side. Included is a SMA-to-RP-SMA RG-316 pigtail so you can plug the amp into your AP. The Amp runs on a 6V DC supply - don't know what the current draw is though. The manual claims a 17dB increase in transmit gain and a 10dB increase in receive gain. Interestingly, the Longreach 1 watt amp claims a 15dB increase in transmit gain and a 16.5 increase in receive gain. Refer to PowerAndGainToDecibels.
I've been putting the amp through it's paces, and have compared it to my
Longreach 1 watt amp.I have a
Superpass 8dBi omni on top of a 13 metre mast at my node - Node GMR. It was connected to a SVEC AP inside my house, and I used to have the Longreach amp inline - in locally powered mode. I shelled into Node GES and ran Wavemon. He has a 13.5 metre mast with a 25dB conifer on it pointed at me. We run on Channel 4.Here are the Figures from Node GES
| SVEC/No Amp | SVEC/Longreach | SVEC/DSE-NZ | ||||
| Link Quality | 54/92 | 80/92 | 78/92 | |||
| Signal Level (dBm) | -66 | -53 | -55 | |||
| Noise Level (dBm) | -100 | -100 | -100 | |||
| Signal-Noise Ratio (dB) | +34 | +47 | +45 |
I now use a Minitar as my AP, here are the figures with the DSE Amp inline:
| Link Quality | 78/92 | |
| Signal Level (dBm) | -53 (dips into -52) | |
| Noise Level (dBm) | -100 | |
| Signal-Noise Ratio (dB) | +47 (dips into +48) |
As a control I also ran my laptop in my office with an Enterasys card (using the internal antenna) and ran
Knoppix STD on it. Here are the Wavemon figures:| SVEC/No Amp | SVEC/Longreach | SVEC/DSE-NZ | ||||
| Link Quality | 20/92 | 28/92 | 27/92 | |||
| Signal Level (dBm) | -75 | -65 | -66 | |||
| Noise Level (dBm) | -93 | -92 | -91 | |||
| Signal-Noise Ratio (dB) | +15 | +27 | +25 |
These figures from my office are a bit rubbery because I was sitting right next to the laptop and there was a lot of fluctuation. I did stare at the screen for a long time however and wrote down the most stable figures.
I don't have a SMA-to-N-type pigtail yet so I can't plug the amp into any of my cards. So I have yet to run wavemon on an interface that actually has the amp plugged into it. I plan on doing so soon so I can get a good idea of the noise figure of the DSE amp.
Any other suggestions for testing? -- DanFlett 170304
Update: 03/09/2006 On the subject of these Dick Smith Amps.
I (another mw member), bought one an amp that looks (and its specs) are exactly as the dse one.
There obtainable for around $130-$160 from citytechnology.com.au and have a brand name of micro-beam
Version 7 (current) modified Mon, 26 Jul 2021 12:49:28 +0000 by steve
[EditText] [Spelling] [Current] [Raw] [Code] [Diff] [Subscribe] [VersionHistory] [Revert] [Delete] [RecentChanges]