RF Explorer...an interesting item from the Seeed Studio  - Page 1
Forum section: electronics / general

author: Fraser
author_rank: Super Contributor
timestamp: June 10, 2012, 12:30:02 pm
content: Attention all RF Geeks.....In another thread I was pointed to the RF Explorer from the Seeed Studio (Thanks Kripton2035).It looks a useful little gadget so I have just ordered the 'full Monty' ISM Combo version (sadly on backorder) for GBP139 delivered from a UK agent.Take a look here for more info:http://micro.arocholl.com/Aurora

author: olsenn
author_rank: Frequent Contributor
timestamp: June 10, 2012, 01:37:48 pm
content: This looks to be a useful tool for those who specifically want to work in the 433MHz, 868MHz, 915MHz, & 2.4GHz. I would not use this thing for anything other than seeing that you have power in the desired spectrum bandwidth. If you intend on doing anything with calculations, ESM testing, or precision work, then you will need an actual spectrum analyzer. There is no tracking generator on these, the sweep speed is undoubtably slow, and the max input power is probably less than 5dbm (this makes it useful only with an antenna)All these restrictions in place, this is definately the cheapest solution for anyone whos requirements are satisfiable with this device.

author: kripton2035
author_rank: Super Contributor
timestamp: June 10, 2012, 01:53:58 pm
content: to "better" play with ISM band, I'm planning to buy this thing (and the arduino I already have...)but this rf explorer is definitely worth it as I can't afford to buy a good spectrum analyzer ...http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=320920875394

author: Fraser
author_rank: Super Contributor
timestamp: June 10, 2012, 02:02:16 pm
content: I struck lucky today and bought an 'as-new' RF Explorer for only GBP65 and its in the UK so I will get it next weekThe model I bought is the 2.4GHz base unit but I have ordered the sub 1GHz upgrade from Seeed Studios for only GBP37 delivered to the UK.I totally agree with the comments regarding using it for serious SA work but I already have some 'real' Advantest spectrum analyzers (R4131D & R3361A), and this will be used only for indication purposes. I also own the Metageek Wi-Spy 2.4X but that cost me GBP20 more than this unit ! As this is a community orientated project I hope the development continues. They are about to release a 5-2700 MHz upgrade board for $140 with 5GHz capability development to follow !It looks a decent enough unit for non critical signal monitoringfor me its GBP65 well spentAurora

author: KD0CAC John
author_rank: Frequent Contributor
timestamp: June 10, 2012, 03:28:50 pm
content: I left a message , hoping to see the wide-band package soon .My main interest is ham & wifi .

author: Fraser
author_rank: Super Contributor
timestamp: June 10, 2012, 07:14:25 pm
content: There is lots of user community detail and feedback at the RC Group:http://www.rcgroups.com/forums/showthread.php?t=1402665Accuracy detail here:http://micro.arocholl.com/index.php?option=com_content&view=article&id=71:accuracy-precision-and-resolution&catid=42:faq&Itemid=68Nice Reviews here:http://www.tmworld.com/article/521074-Can_a_129_spectrum_analyzer_be_any_good_.phphttp://forums.prosoundweb.com/index.php?topic=136565.0http://jwsoundgroup.net/index.php?/topic/10548-rf-explorer/http://www.rcgroups.com/forums/showthread.php?t=1506644http://www.dvinfo.net/forum/all-things-audio/500753-spectrum-analyzer-working-wireless-mics.htmlhttp://jwsoundgroup.net/index.php?/topic/10355-handheld-spectrum-analyzer/Schematic attachedAurora

author: trevwhite
author_rank: Frequent Contributor
timestamp: June 10, 2012, 11:42:18 pm
content: Looking at the specs of these things I came across the following.Amplitude stability and accuracy (typical): +-3dBmThis doesnt sound too great does it?Trev

author: touchh
author_rank: Contributor
timestamp: June 11, 2012, 04:48:28 am
content: Here's a bit of an alternative if you need something cheap, but its not portable:http://www.ebay.com/itm/DVB-T-TV-Realtek-RTL2832U-Elonics-E4000-Radio-64-1700-MHz-SDR-Black-P250-/170836574130?pt=US_Video_Capture_TV_Tuner_Cards&hash=item27c6a73fb2tuners and SDR#http://sdrsharp.com/or if you prefer GNU radio is also another powerful tool you can use with it.more info on the project herehttp://sdr.osmocom.org/trac/wiki/rtl-sdrIt gives you up to 3.2Mhz of bandwidth over any part of the spectrum between 64 and 1700mhz, sure the 8bit I/Q samples kinda suck, but it works pretty good.At-least in my area, there is a ton of 433 traffic from what I guess to be wireless weather stations/security systems.In reply to the original topic, I had one of these and liked it, it was to me very sturdy, inside build quality was just as nice.. wish I had took pictures now. I sold it and plan to get the ISM Combo + 2.4 version when its back in stock. The only thing I really hated on my version was the power button on the bottom! what a silly place to put it. Looks like its been moved to the top now.

author: Fraser
author_rank: Super Contributor
timestamp: June 11, 2012, 08:31:24 am
content: trevwhite,This page explains all:http://micro.arocholl.com/index.php?option=com_content&view=article&id=71:accuracy-precision-and-resolution&catid=42:faq&Itemid=68The +-3dB relates to the accuracy of a reading. Yes that is a wide range but is it repeatable ? That is the real question. This unit is a little like a cheap multimeter....there may be an accuracy error but provided it does not drift, the readings are all relative to that error and so valid for comparison purposes. If the readings wander +-3dB on the same signal over time....now that would be bad !Please remember, this is a Signal Monitor........i.e. is there a signal and roughly how big is it compared to others. This is fine for checking that a transmission is present, roughly on frequency and hopefully without uncontrolled harmonic content. The RF Explorer is NOT a true Spectrum Analyzer as it lacks close tolerance accuracy in all respects. I have already suggested a suitable sensitive field strength meter as the way to go for signal peaking. The RF Explorer will just show you your transmission and is not going to provide highly accurate RF field measurements.It depends on what you want the unit for, This is a very cheap spectrum monitor with adequate performance for that task but I fear that you desire more accuracy and that will mean spending a little more money and buying a good used Spectrum Analyzer. I picked up a lovely Advantest R3361A SA with built in tracking Generator for only GBP500 last week. There are bargains to be had. But considering this RF Explorer cost me about the same as some of my less than perfect portable oscilloscopes, I think it good value for money if it meets the desired tasking requirement.Kindest RegardsAurora

author: trevwhite
author_rank: Frequent Contributor
timestamp: June 11, 2012, 08:38:21 am
content: Hi Aurora.I am really looking for repeatable measurements. I am not looking to get perfect results right now. I just need to know I am in the right ball park and be able to make relative measurements. So for tuning an antenna, I can trim until I find the peak is good enough.I am currently looking into the RTL-SDR stuff. It looks interesting.ThanksTrev

author: trevwhite
author_rank: Frequent Contributor
timestamp: June 11, 2012, 09:08:06 am
content: Aurora, dont suppose you are looking at any other spectrum analysers on ebay that look decent for not much money. £500 is doable if it works.I think it would be really useful for other stuff as well.ThanksTrev

author: Fraser
author_rank: Super Contributor
timestamp: June 11, 2012, 04:55:35 pm
content: trevwhite,I have two Advantest TR4131 10kHz to 3.6GHz spectrum analyzers in good condition looking for new homes.Where are you located ? I am in the UK and the units are heavy, so overseas posting would be too expensive and difficult. If anyone else in the UK is looking for a 'real' spectrum analyser, PM me and we can discuss value. I attach a picture of the TR4131 (not my units)Aurora

author: trevwhite
author_rank: Frequent Contributor
timestamp: June 11, 2012, 05:33:23 pm
content: Have sent you a message, Aurora.Trev

author: terabyte
author_rank: Contributor
timestamp: March 11, 2013, 06:25:20 am
content: I have one of these and check out how I have been using it to solve some RF interference issues on my quadcopter projects.http://forums.openpilot.org/topic/16802-please-help-me-dissect-my-latest-crash-updated/?p=184562