LAST UPDATE: 04/06/2012

Latest News:

- Added how to mod a lawmate Rx to add the 900Mhz feature

Hi Folks after a long sleep here I am again to tell you there is another player on the market:



Price: 72USD incl shipp

Brightness Adjustment,1 W LCD screen.... Tempting since I do not recommend the lawmate anymore because I had one overheating on me (although I did not remove heatsink) and got other reports of the same issue.

I don't need another Tx at the moment but if you are willing to make a 1$ donation to this cause I will purchase it and review it properly for the community.

- If you are interested in upgrading your tuner with a comtech, please read this carefully (you'd better have an o-scope)
- My last conclusions about Circular Polarisation
- CP vs Stock antennas review: http://www.rcgroups.com/forums/showp...postcount=1723
- CP Antennas review made by me
- Mod (not easy) for the Knob Receiver (see Don't Touch this category) Other mods for the not so good category can be found here: http://esquinaelectronica.blogspot.com/
- No problems between Lawmate receivers and CP Antennas anymore!
- Again: New jitter free servo found! And cheaper then the previous new one, Made the Test myself, not a single glitch (only if you make the antenna touch the metal tip of the gears)


DISCLAIMER: FOR US CITIZENS PLEASE REMEMBER THAT THE ONLY LEGAL CHANNEL FOR THIS SORT OF ACTIVITY IN USA IS 1280 Mhz

For Those who don't want to read it all:

Regarding the analysis the RC community made, the best suggestion is: Fox-800 (see 2nd Post) and the lawmate Receiver on the Rx side.

Here a small chart to help you choose:




Chart containing the available frequencies

For a small aircraft you can choose the lawmate 500mW too but beware, it is fragile, expensive and does NOT have 1280Mhz.

Alternative: use the small Tx from readymaderc.

GENERAL INFOS

Antennas

Stock Antennas give good results but here are some better ones

Tx: Go for IBcrazy's inverted Vee, better results and lighter



Even Better: Skew-Planar Wheel circular polarized omni antenna



or Cloverleaf (apparenty the best for omnidirectionnal)



But Wayyyyy more complicated to DIY

If you have problems between CP Antennas and lawmate receiver it can be fixed, check here.


Rx:
- Goof Proof Antenna from RC CAM or IBCrazy's FAST Patch

- DIY Bi-Quad Best One for an Antenna Tracker.
- Moxon Rectangle or other Yagi (Easier to build - Cheapest)

- The Helical Antenna, IBCrazy's favorite





- For long Range Buy 1.2Ghz Yagi 21USD Do not Forget pigtail 5.5USD. Results: 17km on 1280Mhz


- Buy 1.2Ghz Patch (Expensive 45USD i.sh. - tuned for 1160Mhz you have to open it and trim the small plate to tune it to higher frequencies)



For Example: My Bob Tx/Rx was giving me 600m usable Video Stock and 1.4km with a Vee and a Homemade Fast Patch. Now my RC link is the weak link.

Servos

Some Servos do jitter a lot near a 1.2Ghz Vtx , the more you get close to 900Mhz the more you can have this Problem.

Here an example: 1080Mhz + HXT900

Servo jittering due to RF Interferences (1 min 58 sec)

Solutions:

- Try ferrite Cores and braided wires on your servos.
- Change frequency to go near 1.3Ghz (does not work with the HXT 900)
- Change your servos to one of these (If you do not agree please give feedback):

> The ones that I recommend now are the Corona 939MG
> Really Cheap ones (watch out, maybe mechanical quality is bad)
D933MG from HK but does not center well (tried it for Pan)
> Cheaper tested and still Metal Geared!: DS-929MG
> Esky EK2-0508
> HS-5085MG
> HS45, HS56, HS65MG, HS82 + all the Hyperion Atlas models
The EMAX servos @ 1280Mhz.
hs -5065mg and 5485hb's

Avoid those:

9g blue ones do (rctimer, hextronic, turnigy, towerpro), Hitec HS82MG (Metal Gear), TPro MG90s and MG16R

General Tips / Tricks:

- Remove heatsink and place the Tx in the airflow on your plane, you won't need extra heatsink (not True for the lawmate).
- If your new Rx antenna needs an SMA connector you have 2 solutions:

Add an SMA port
Buy an F to Sma Adapter

- You accidentely crossed-over + and - and the Tx fried? Here one solution

- Would a Lawmate Rx perform better with this Tx? Not so sure, I did not see any big difference and this thread confirms it too. But more testing would be appreciated,

- If you are using only one battery and/or having interferences use this LC Sander DIY filter

or

12 V Regulator

Here

Watch out for RFI though, but it's a good tool for most of the Tx who loose power with voltage drop (NOT the lawmate)




Here a even a better one:


FOX-700 aka the BOB Tx

One of the most popular in the 1.2Ghz FPV Community



Price (incl. ship.): 57.9USD
Buy
Manual (watch out some infos are wrong see beyond)
Real Tx configuration:


PCB pictures

Hints:
- has 1280Mhz (legal for the US)
- Works better (more power) when tuned on the lowest channels
- Loses frequency lock around 10v so do not use it in a single battery setup or use a regulator to feed it with 12v constantly
- Kills 2.4Ghz RC range in some situations.
To solve the problem: use 1080Mhz (helps a bit), if not use a low pass filter:
900Mhz (if you are on 1080) or 1.2-1.3Ghz 42USD i.sh.

NEW Cheaper Filter

20 USD Including shipping

Other solutions: Change your 2.4Ghz RC antenna to a 8Dbi Patch and/or use a Wifi booster.

Auto Scan Mode

Quickly press and release either control button (up or down) till you get to the first channel that you want to monitor. Then press and hold either control button until you see the dot, like "6." instead of just "6". Repeat with other channels that you want to monitor until you have selected all the channels you want to monitor.

Quickly press and release either control button (up or down) till you get to the "A" channel and leave it there. Soon it will change to the first selected channel and then the second... On mine, with no antenna, and no signal, it plays each channel about 6 seconds and then jumps to the next channel.

Sunsky 1.2Ghz 400mW

Price: 49USD + shipping (7,44 USD to Europe).
Buy
Antenna length end to end
182mm or 7.25"
Weight
23 grams or .81oz


Sunsky 1.2Ghz 800mw aka Fox-800



The one with the LCD....
Price: 61.41USD + shipping (12 USD to Europe + 3$ Paypal fees)
Buy
Antenna length end to end
182mm or 7.25"
Weight
23 grams or .81oz

Many reports showing this one is very good, up to 2-3 kms Stock configuration
Real Power output: 500mw

Hints:

- Tx is smaller and is more powerful then the fox-700 See Vs Test here
- Frequency choice made with a button not a jumper
- 6-7-8 Channels seem to work the best
- Rx is the same then fox 700



Lawmate 1000mw 1.2gHz AV link

I just tested it (22/11/2010) in the exact same conditions as previously with the BOB and I can confirm it has more power on the same 1080Mhz channel.

At 1km I had 0 signal degradation whereas with the BOB some small white lines appear.


Price: 120$ Tx +Rx without shipping (holy moly!)
Buy
Real Power output: 1W



Ch1. 1080
Ch2. 1120
Ch3. 1160
Ch4. 1200
Ch5. 1010
Ch6. 1040
Ch7. 1240
Ch8. 1280


Hints:

- NEW Mod to make it work on 900Mhz + 1.2
- manual
- No power loss during voltage drop between 12 and 10V (internal regulator)
- If you remove the Heatsink be very careful when using it on the ground or it will be dead after a while.
- Weight with heatsink: 38g = BOB without Heatsink!
- Here one way to fix it.
- ch1,2,3,4, the A/B switch should moved to A, when u want to get ch5,6,7,8, the A/B swicth should be moved
to B, then power the Tx and Rx.

More details here



1.2GHz 700mW 15 Channel Digital Wireless AV Transmitter and Receiver SR-700mW

Here a detailed review from mictronics

In a nutshell: Powerfull + Cheap but bulky.

But some reports of overheating

43USD incl. sh.

Link



Infos:

Reference: 28dB = 630mW 29dB = 800mW

Channel Frequency [MHz] Power [dBm]
1 993 28.3
2 1020 28.4
3 1050 28.3
4 1060 28.2
5 1080 28.2
6 1100 28.0
7 1120 28.0
8 1140 28.2
9 1160 28.6
A 1180 28.7
B 1200 28.6
C 1220 28.3
D 1240 27.9
E 1256 27.6
F 1280 27.3

Interesting facts:

- The receiver is rated for the frequency range 0.9 – 1.56 GHz, split into 28 channels!
- Rx seems of good quality (but not the best saw filter)
- Output power is constant with the channels and more important it is compliant with the specs which is good (only Lawmate does it among the others)
- Watch out Tx case needs to be changed because it is heavy
NEW: Reports of burned devices due to bad design, watch out!

Video review:
IBCrazys 2cents: "The bad thing about this unit is that it loses frequency lock at 8.75V"

15 channel 1.2GHz VTX Testing and verification for FPV (2 min 34 sec)

STANDALONE TXs:

1.2GHz Mini 200mA DC 8V 800mW Power Supply Transmitter ESTX800
Caution: Fixed on 1080 Mhz
Lightweight (under 10g)

Buy 19 USD inc.sh.


Need feedback on this one.

Last infos:

it uses quartz x 256 fixed frequency. So it depends on what quartz you got. With 5Mhz one you get 1280Mhz.
Maybe it's a coincedence, but the round sticker on mine tx is "2" and the frequency corresponds with the second available channel on Fox's 12ch recievers (Nr.5 1120Mhz)
And power is noway 800mW for sure. On mine it's 70-100mW. Draw current is 100-110mA, 9V voltage
___
from 3s it draws 180 mA, and I think power is more than 500mW, at least compared with BOB 700mW disipation.
About range, I can cover at least my 800m flying field, not tried farther.


COMING NEXT: THE "DON'T TOUCH THIS" CATEGORY




See the knob? >>>> NOT GOOD!

NEW: You can mod those to control them with a IR Remote but it's a bit hardcore for the non Electrofreaks


But If you already bought the crappy 1.2Ghz camera that goes with it........you have no choice because those cameras won't work with the other Rx.


1.2GHz 800mW Security CCTV Transmitter for CCTV Camera
Buy 27USD

One member reported this was a good deal but I personnaly tested it in the exact same configuration as my BOB Tx and completely lost signal at 250m (not even a fade out). Several Tests were made. So I guess you should stay away just to avoid a bad surprise like I had.

I recommend useing a "lawmate" video rx

over those that comes with the combo

edit it also works well with that $27 one

Originally Posted by iacei

Other reliable combos:


Hints:

- 6-7-8 Channels seem to work the best
- Rx has a 17Mhz Saw filter which is good (no need to make the Saw filter mod)

Chart containing the available frequencies

Did you notice if this hint applies only to Sunsky units, or both Sunsky and BOB units?

Only for the sunsky.

In fact the BoB Rx seems to have a classic SAW filter which would be interesting to mod but I di d not find someone who did it on the bob.

Oh, sorry I meant specifically the part about channels 6-8, but I assume that is Sunsky as well.

Maybe I should have tried the Sunsky instead of the BOB but I though they were the same at 1st.

I have recently purchased the sunsky 1.2 Ghz 800mw system. We did a ground test with a friend. Vtx 5th floor of a building on the skirts of a hill, Vrx drove away with a car. We had clear video without any interference at 2.8km LOS. This of course was without and RC equipment around. Stock antennas out of the box, no patch, no diversity etc. This was on channel 8.

GOK

Nobody is talking about this one ?
http://www.dinodirect.com/1-2GHz-Min...0.html?cur=EUR
It's fixed on 1080mhz.
I've ordered one, hope to have it in a week

Give us feedback when you test it. I think Renatoa reported it is a good one.
.
Did a test today to check some things:
I confirm the custom Vee is way better then the stock rubber duck antennas
I did not see a big difference between the lawmate rx and the Fox one (not on a very long distance though)

After shipping the Sunsky one is almost the same price as a Lawmate, isnt it? Why you get the Sunsky over the LM in this case... the extra "300mw" (if they are really there). I thought LM was about the best you can get if you dont mind 5v power. Or does LM not have the legal channels (USA)???

the lawmate is 12 volts
and is a much better video rx

all channels are available with the lawmate video rx

Originally Posted by Derek_S

After shipping the Sunsky one is almost the same price as a Lawmate, isnt it? Why you get the Sunsky over the LM in this case... the extra "300mw" (if they are really there). I thought LM was about the best you can get if you dont mind 5v power. Or does LM not have the legal channels (USA)???

Originally Posted by Derek_S

After shipping the Sunsky one is almost the same price as a Lawmate, isnt it? Why you get the Sunsky over the LM in this case... the extra "300mw" (if they are really there). I thought LM was about the best you can get if you dont mind 5v power. Or does LM not have the legal channels (USA)???

Where do you find a Lawmate Tx/Rx for 65USD shipped?

I had a Lawmate Tx/Rx for more then 100USD shipped and the Tx was good but a bit fragile.

Oh, sorry, I rechecked the lawmate is about $30 after shipping. But still, $30 difference for a 'better' Rx and Tx, if you dont mind 5v?

I say 'better' becasue I do not have a Lawmate, I just have asked several of the veteran FPV'rs here and ALL of them I asked told me Lawmate was the way to go. Granted they also are mosly using the 2.4 channels. And When I asked David22, he at least uses a LM RX. (Thanks David for your advice)

BUT, I also do not have a Sunsky unit. I have only 2 BOB units, which for me are working out to be a waste of money. Range just really sucks, not even counting that I am getting local interference at my favorite field (but not the BOB's fault I guess). I wish I would have tried Sunsky, as they seem to be better units. Kmart is getting 1 mile with stock omnis? JEALOUS

If you do not reach good ranges with 2 Bob units I guess there is something wrong with your setup. A sunsky would not help you out here.

It not just me. At least one experienced member (IBCrazy) has the same problem with BOB only 1000' with stock units. Check his posts if you want more info, he is pretty knowledgeable, more than I am. I have not tagged along in the BOB dedicated thread lately, so there may be more, or IBCrazy and myself may be alone in this.

I also get much surperior range in the exact same airframe with a cheap FOX style 900mhz system. The BOB fades at 1000' for me very badly, as it did for him. I get a lot of interference here in the city, too, which is not entirely the BOBs fault but could be intensified by a presumed poor receiver sensitivity of the BOB. I have not yet dared to find the limit of my 900 sytem, but I have gone at least 2000' on 500mw.

Another discussion on BOB is that it has an F type RF connector, 75ohm, where most of use use SMA. This poses another albeit minor problem with (possibly) mismatched impedance and connector/adapter losses. Check my thread on multipath for a little discussion on that. I am not sure what Sunsky has? SMA hopefully?

I really dont think it is a airframe systems problem as I have tried various configurations with proven equipment (at least what works for others on this forum). I am not saying the BOB is bad, I am just saying it hasnt worked as well as a 700mw unit should in a rural area. I have not seen very many people say it is working great for them (but I have not searched thoroughly) but I do seem to keep finding good posts the Sunsky system. I would never had thought they were different, but perhaps they are.

I also tried it in a completely different airframe with totally different and very simple/mimimal electronis with the exact same results. I will need more testing to confirm, but it just looks like I might have got a bad draw as far as quality control goes.

EDIT: I just spent a bit looking through the thread. I have not found any consensus, but maybe just one out of every few units is really good? I really dont know but there do seem to be quite a few people happy with the BOB.