Mavic Radio Mods Primer

[mnoutdoors]

Similar unit packs of 6 for $12.00 with free shipping

https://www.amazon.com/eBoot-LM2596-Converter-3-0-40V-1-5-35V/dp/B01GJ0SC2C

 

[beanbubba]

Similar unit packs of 6 for $12.00 with free shipping

https://www.amazon.com/eBoot-LM2596-Converter-3-0-40V-1-5-35V/dp/B01GJ0SC2C

Thanks sir, just ordered a set. You can't beat that price.

 

[fileophile]

That picture was of an old design configuration. The group has made several improvements since then (but they are scattered across several threads). I will try to get an updated bird put together soon and document all the parts.

Looking forward to the latest design parts list, thanks.

 

[beanbubba]

Looking forward to the latest design parts list, thanks.

In the mean time, catch up on the last few months of these threads:

Mavic Pro Battery Mod

Aircraft Antenna Mod

Mavic Pro Factory Battery Controller Mod

 

[beanbubba]

Mavic Radio System Observations 3.2
Aircraft and remote controller new baseline based on variable output.

 

[beanbubba]

I can’t answer that, but I think he may have a bad amp with the 8w but I do love what his test says on RX gain and hope that is correct. I’m not smart enough to do that test

I just received the amp @mnoutdoors sent me. I also found a another supplier and got that unit today as well. They look identical, but show a different model number on the backside. Anyway, I did some basic tests and they both put out 35.5 dBm at 19 dBm input (I ran up to 24 dBm input, but no increase in output).

 

[mnoutdoors]

It will be interesting to see how this pans out 35.5 is better than the last test at 30.7 in the DBM world 5 is huge

 

[fileophile]

I see what you mean about the cost of LMR900. I guess LMR600 will have to do. I can find Times Microwave LMR600 (not db) at Cart - Free Shipping on Most Orders Over $99 at DX Engineering for what seems a good price. But I was hoping the vendor might have the QMA connectors I wanted also, and it doesn't seem they do (other than "special order" with a longer lead time). Do you know of a good place to get both? (I want QMA connectors because my RC has the Titan Atlas amplifier on it, and with QMA I can just pop off the Titan and plug into the outdoor antenna cable).

 

[mnoutdoors]

Your most likely going to go from LMC 600 to a type n connector then adapt from the N to a short cable with sma connectors

Everything should be on eBay

50-200' TIMES® LMR600 LOW LOSS FLEX COAX RF CABLE N TYPE Male Female to Male Fem | eBay
Cable

Search N connector to sma

Search qma to sma ( or just get them from James @ Titan )

 

[fileophile]

Thanks. Isn't there a loss though through each adaptor? SO going from N to SMA to QMA will be more lossy than straight from cable to QMA? Or is this loss insignificant?

 

[mnoutdoors]

.30 dbm but you can’t just just go from a LMR 600 to your controller that’s 5/8” cable! You do want some movement don’t you

 

[beanbubba]

.30 dbm but you can’t just just go from a LMR 600 to your controller that’s 5/8” cable! You do want some movement don’t you

Times microwave is a good source. I personally use L-com, but you also need a flexible pigtail at the end of the LMR600 cable to attach to your gear. Below is the LMR200 pigtail I use.

LMR600
N-Male to N-Female 600 Series Assembly 50.0 ft - CA-6NMNF050

LMR200
RP-SMA Plug to N-Male 200 Series Assembly 10.0 ft - CA-RSPNME010

 

[beanbubba]

I see what you mean about the cost of LMR900. I guess LMR600 will have to do. I can find Times Microwave LMR600 (not db) at Cart - Free Shipping on Most Orders Over $99 at DX Engineering for what seems a good price. But I was hoping the vendor might have the QMA connectors I wanted also, and it doesn't seem they do (other than "special order" with a longer lead time). Do you know of a good place to get both? (I want QMA connectors because my RC has the Titan Atlas amplifier on it, and with QMA I can just pop off the Titan and plug into the outdoor antenna cable).

QMA is a speciality custom interface. You won't find commercial products using this. I understand your desire, but if you want a custom rig you will need to stick with N and RP-SMA connectors. You probably can find some adapter fittings somewhere to do the conversion for you. I agree the QMA connectors are cool, just not readily available for custom applications.

 

[beanbubba]

Thanks. Isn't there a loss though through each adaptor? SO going from N to SMA to QMA will be more lossy than straight from cable to QMA? Or is this loss insignificant?

Loss on short cables and connectors is negligible.

Here is a web app that you can run the calculations for yourself:

Welcome to Times Microwave | Coaxial Cable - Attenuation & Power Handling Calculator

 

[beanbubba]

It will be interesting to see how this pans out 35.5 is better than the last test at 30.7 in the DBM world 5 is huge

I am sure that first amp was defective and I am tossing it out. I have these 2 new units to continue testing with now.

I also just found this unit and initial tests are strong:

https://www.amazon.com/gp/product/B00CR6V0GS

I am going to do a new video very soon and re-test all the amps including this newly found unit. I now have a 24 dBm pre-amp and can over drive all the amps now to their full potential output. The last amp video is probably a couple dB short based on the latest tests I performed on the 20 dB continuous carrier broadband amp (that actually tested out short of 20 dBm after the fact).

I also did some preliminary tests on the broadband amp's and see potential using these on the RX-Only ports. More details coming soon.

The next videos in the series will show the receiver sensitivity on these amps and how important this is depending on the applications and the power output from the mavic radios.

 

[mnoutdoors]

This this one is 20 watt might have to get one for testing
It would be a good candidate for a Tower amp ( you know lots of cable loss )

 

[beanbubba]

View attachment 34873 This this one is 20 watt might have to get one for testing
It would be a good candidate for a Tower amp ( you know lots of cable loss )

I didn't see a URL for this, do you have it?

 

[mnoutdoors]

I got it from Alibaba.com supplier ( China direct)

Specifications:

1. Frequency: 2400-2500 MHz.

2. Operation Mode: Bi-directional, half-duplex, Auto-Switching via carrier sensing.

3. ultra low power consumption: 620mA@Pout 36dBm 48V

4. Input Power:8dBm (Min.)-26dBm (Max.).

5. output Power 9~ 43 dBm.

6. EVM: 4%@36dBm 802.l l g 54Mbps OFDM 64QAM BW 20MHz

7. Output Power: 20000mW/43dBm nominal for 802.11b/11Mbps.

8. Connector: SMA Receptacle, 50 ohm.

9. Transmit Gain: 17dB土1 nominal.

10. Receiver Gain: 20dB土1

11. Receive Noise Figure: 2.5 dBm nominal.

12. Operating Temperature: -40 to 70 degree.

13. Operating Humidity: Up to 95% relative humidity.

14. Material: Cast Aluminum.

15. Size:225mm ×12lmmx24mm

16. Weight: 1000g


240.00 US for 1 sample

 

[fileophile]

Got my LMR-600 cable ordered and the pigtails. Found some pigtails on eBay going from N to QMA, which I think will work.

While waiting for that stuff to arrive, decided to look into those Mavic front leg antennas. What kind of antennas are they? They seem dirt simple -- I don't even know how they can work as well as they do. About 2.5 inches long with a single connection point in the middle. Then the coax runs to some kind of board connection -- it that a U.FL connector there?

Would these +6db antennas work better as front legs for the Mavic?

https://www.amazon.com/HIGHFINE-2-4...F8&qid=1523152903&sr=8-3&keywords=2.4+antenna

 

[mnoutdoors]

View attachment 34873 This this one is 20 watt might have to get one for testing
It would be a good candidate for a Tower amp ( you know lots of cable loss )

It on its way ........... about one week DHL