HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Feb 26, 2012, 06:28 PM
Registered User
United States, TX, Mansfield
Joined Jan 2012
520 Posts
Mini-Review
Video Transmitter Review: Foxtech 5.8G 500mw TX

Video Transmitter Review:

http://www.foxtechfpv.com/58g-500mw-tx-p-247.html

5.8G 500mw TX
Model: TX58500


Introduction:

I bought one of these along with a 305 Receiver from www.foxtechfpv.com

I will admit that I did not have high expectations due to the many bad reports from users about it burning out prematurely.

It seems that to create a 500mw 5.8ghz transmitter, they basically just took their existing, proven 200mw transmitter and altered it to supply a higher voltage to the amplifier(s)

They then added a large heatsink and cooling fan to compensate for the higher temperature the amps will operate at with the higher voltage/higher output wattage.


I get what they did here. They are basically "overdriving" the 200mw board, and trying to provide adequate cooling to compensate.

This is not necessarily a bad thing. It CAN work successfully if done correctly. People have been doing it successfully with PC processors for years. However, doing it SUCCESSFULLY can be tricky...


I have to admit, I was intrigued about this. I wanted to have one to do some tests with to see how it performed, so I ordered one...


Initial testing:

Well, let's just say the testing didn't go well. It started out OK at first. I connected everything up, and got very clear video and audio (albeit, the TX and RX were only a few meters apart from each other)


At first, I just had the stock whip antennas on both the vTX and vRX. The video and audio were clear and good at short distance, and the tx was not getting too hot even sitting on the bench (the fan and heatsink were doing a good job)

One annoyance is that the fan is a bit loud, and the microphone is mounted on the board not far from it, so you get a loud buzzing noise at all times on the audio. I would have likely disabled the on-board mic, and used an external mic instead because of this...


Performance testing with RCHP omni antennas:

OK, initial test is good. However, when moving the transmitter around a bit, I did get quite a bit of multipathing interference (as to be expected with the stock whips)



So, next, I put a RCHP SPW (right-hand circular polarized skew planar wheel antenna) purchased from readymaderc.com on the vRX for the next test. Reception and multipath rejection were roughly the same as the stock whip. Perhaps BARELY better, but hard to tell.


And lastly, here's where I ran into trouble. I next tried to put another RCHP SPW (also from readymaderc.com) on the transmitter, but found the stock antenna is GLUED ON! Yes, they glued it on for some insane reason. Probably to make sure some user doesn't power it up with no antenna attached, I assume???


Well, I tried my best to remove it, but ended up destroying the transmitter module in the process. That thing was REALLY glued on!!! Even heating the rpsma connector with a torch to the point it de-soldered itself was not enough to free the antenna completely.


Testing ended. Transmitter destroyed by me trying to remove it's antenna...




Remedy?


I emailed foxtech about this, and told them I broke it trying to remove the antenna, because it was glued on by some insane, derived from alien technology glue that can resist heat in excess of 700F! (No, not really. I just said it was glued on, and I broke it trying to remove)

To their credit, they responded quickly and politely. To summarize their response, it was basically: Yeah, it's not meant to be removed, and breaking it while removing it is not covered by any sort of warranty...

They did offer to have me send it back for repair at a cost, but did not give any sort of estimate as to the cost, or offer any details regarding who would pay shipping each way, etc...




I have responded and told them I am sure it just needs a new transmitter module. I asked them if they can send me a new one. I am waiting for a response (still less than 24hrs as of this writing) - We'll see what they say...



As far as I know, this is the ONLY transmitter of any frequency or power, advertised commercially for use with FPV that comes from the factory with the antenna GLUED ON! To me that is just ridiculous, but if they are going to do it, they should at least post a disclaimer on their web site about it. I provided this feedback in my email response to them as well.



Conclusion:

So, in summary, I would definitely NOT recommend this transmitter to anyone for any application at any price, solely because they glue the antenna on. It's a shame, because I think with adequate cooling, it could possibly work quite well for FPV otherwise...



I want to be clear that my experience with foxtech has been positive aside from this. Fast shipping, good tracking, fast email response, etc. If they just hadn't glued the antenna on, this review might have been MUCH differently, but we'll never know


We shall see how their response regarding my request for a new transmitter module goes. If they send me a new one for free, or even at a discount, then that will redeem them a bit in my mind...


Update: As far as I am concerned, the matter is concluded. Foxtech has offered to replace my vTX with one that does not have the antenna attached If I send my broken one back to them. I have decided not to send it back for replacement and instead just cut my losses...
CTvxl is offline Find More Posts by CTvxl
Last edited by CTvxl; Mar 10, 2012 at 09:01 PM.
Reply With Quote
Sign up now
to remove ads between posts
Old Mar 03, 2012, 12:40 AM
Registered User
United States, TX, Mansfield
Joined Jan 2012
520 Posts
Fu at Foxtech has asked me to send the TX back to him for inspection. He said that Foxtech will pay return shipping to send it back to me, regardless...

He also has agreed to send me a unit with the antenna NOT glued on. He seems like a reasonable person to deal with. If you are thinking about ordering one of these transmitters, perhaps try sending Foxtech a message first requesting one without the antenna glued on. If you tell them you UNDERSTAND THAT POWERING IT UP, EVEN FOR A MOMENT WITH NO ANTENNA can and likely WILL damage it, then I'm sure they will send you one with no problem...

It seems they glue the antenna on because novice users often destroy the TX by powering it with no antenna attached... At least, that is the impression I get...


Once I get the replacement unit, I will mount it on my test platform, which is on an RC car, and see how it performs...
CTvxl is offline Find More Posts by CTvxl
Reply With Quote
Old Mar 04, 2012, 09:46 AM
Registered User
United States, CA, Fairfield
Joined Sep 2001
21 Posts
Keep us informed; I'm interested in your long term use of this unit!
kscheck is offline Find More Posts by kscheck
Reply With Quote
Old Mar 04, 2012, 09:57 AM
Registered User
Romania, Dolj, Craiova
Joined Sep 2007
14,483 Posts
Can you post a picture of the sma connector area, please ?
renatoa is online now Find More Posts by renatoa
Reply With Quote
Old Mar 04, 2012, 11:28 AM
Registered User
Norway
Joined Feb 2012
85 Posts
I have the same system. Earlier this week I was going to put on a CL antenna. The original one was also glued on, but I managed to get it off by being carefull with different tools.
RemiWM is offline Find More Posts by RemiWM
Reply With Quote
Old Mar 04, 2012, 12:43 PM
fly by night
BCSaltchucker's Avatar
Joined Sep 2011
5,267 Posts
I made the mistake of buying one of the 500s at first. Never did fly with it, after heeding the advice on here. Been happy with the 4 200mW Txs I eventually bought. I still have the 500, and I live in a fairly cool climate, so maybe it would be OK to use here in winter. Luckily no glue on the antenna - wow, how idiotic of them to glue it on!
BCSaltchucker is offline Find More Posts by BCSaltchucker
Reply With Quote
Old Mar 04, 2012, 02:26 PM
Registered User
United States, TX, Mansfield
Joined Jan 2012
520 Posts
Quote:
Originally Posted by BCSaltchucker View Post
I made the mistake of buying one of the 500s at first. Never did fly with it, after heeding the advice on here. Been happy with the 4 200mW Txs I eventually bought. I still have the 500, and I live in a fairly cool climate, so maybe it would be OK to use here in winter. Luckily no glue on the antenna - wow, how idiotic of them to glue it on!
Yes, and I told Fu that. I told him a better solution to the problem of inexperienced users powering it up without an antenna attached would be to put a big red warning on the web site about it. They could also attach one to the antenna itself.

I would even have understood (but still have been annoyed by it) if they would have just used a very small amount of purple locktite or similar, making it require a tool to remove, but still removable.

I'm pretty sure mine was expoxied on judging from the remnants left in the threads of the antenna. I heated it several times, and the last time overheated it out of desperation to the point it began to de-solder the RPSMA connector from the board. The glue still wouldn't budge. It weakened it somewhat, but it was very tight.

I ripped the RPSMA connector off the board with my last attempt to remove it. I'm sure the heat must have weakened the solder joints holding it in...


I'm planning to use this primarily for on-ground FPV only. And it gets HOT here in Texas, so we'll see how long it lasts

Now I just have to deal with the hassle of shipping this thing back to China.
CTvxl is offline Find More Posts by CTvxl
Reply With Quote
Old Mar 04, 2012, 02:40 PM
Registered User
United States, TX, Mansfield
Joined Jan 2012
520 Posts
Quote:
Originally Posted by RENATOA View Post
Can you post a picture of the sma connector area, please ?

Here you are:




I tried to repair it, but when the connector came out, it ripped a long bit of tracer off the board with it. I fixed it with a single strand of copper as best I could. I have continuity from the center pin past the obvious point of damage, but it doesn't work.

Pretty sure some tiny component got trashed when the tracer ripped off the board.
CTvxl is offline Find More Posts by CTvxl
Reply With Quote
Old Mar 10, 2012, 08:43 PM
Registered User
United States, TX, Mansfield
Joined Jan 2012
520 Posts
Sorry guys, I guess this one's dead.

I just sent Fu at Foxtech an email thanking him for trying to work with me for a solution, but I have decided not to send the vTX back to them for repair/replacement.

The cost and hassle of shipping it back is just not worth it. Maybe I will buy a cheap tx module at some point, and see if I can adapt it or something similar so it's not a total loss.

If nothing else, it has a pretty nice 5v regulator on the top board that could be useful...
CTvxl is offline Find More Posts by CTvxl
Reply With Quote
Old Mar 18, 2012, 07:16 AM
I love to be above the clouds
Joined Aug 2011
326 Posts
any one tried this vtx ? http://www.iftrontech.com/product_in...roducts_id=187
KellyFPVER is offline Find More Posts by KellyFPVER
Reply With Quote
Old Mar 18, 2012, 12:31 PM
Registered User
Romania, Dolj, Craiova
Joined Sep 2007
14,483 Posts
30km, I come !!!
renatoa is online now Find More Posts by renatoa
Reply With Quote
Old Mar 18, 2012, 01:58 PM
Registered User
United States, TX, Mansfield
Joined Jan 2012
520 Posts
Quote:
Originally Posted by KellyFPVER View Post
That thing is a monster!!!

I have the mondo stinger .5w, but haven't played with it yet. Just got it the other day...
CTvxl is offline Find More Posts by CTvxl
Reply With Quote
Old Mar 18, 2012, 02:38 PM
fly by night
BCSaltchucker's Avatar
Joined Sep 2011
5,267 Posts
So what frequencies are Iftron using? Compatible w Foxtech or Airwave?
BCSaltchucker is offline Find More Posts by BCSaltchucker
Reply With Quote
Old Mar 18, 2012, 03:14 PM
Registered User
United States, TX, Mansfield
Joined Jan 2012
520 Posts
Quote:
Originally Posted by BCSaltchucker View Post
So what frequencies are Iftron using? Compatible w Foxtech or Airwave?
From the Mondo Stinger manual:

Output Frequencies: 5.740 5.860 GHz
Channels: 7 channels 20MHz spacing

FYI - I posted the manual and datasheet in my Turbo Vee build thread:

http://www.rcgroups.com/forums/showthread.php?t=1613775
CTvxl is offline Find More Posts by CTvxl
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion 500mW 5.8g tx Moonrider30 FPV Talk 5 Nov 12, 2011 07:07 AM
Discussion Foxtech 5.8G 500mw Video TX/RX and GoPro FPV jdwphotos.com FPV Talk 6 Sep 23, 2011 01:52 AM
Question Foxtech 5.8G 200mw TX weirdness grumpy42 FPV Talk 2 Aug 04, 2011 04:19 PM
Discussion foxtech 5.8g noise/lines mitmit FPV Talk 23 May 13, 2011 05:44 PM