Amp on Extender

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For the pros out there:
I have the amp shown below. I also have the P2V+ RE-700 extender on my controller. Somewhere I read about using this amp that the output of the RE-700 was too much for the input of the Sunhans amp and an attenuator had to be used between them. If correct, where can one be purchased?
 

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That web site is for sale.
 
Purrrrrrrrrfect.
Thanks.
 
I've been using this same amp (slightly newer version) for over a month without any attenuator and it works fine.

I believe the RE-700 maxes out at 100mW output and the Sunhans 2.4 GHz amp can accept up to 100mW (20 dBm) input as per it's spec sheet.

I have the Sunhans Model SH-2500 (shown below) and your photo looks different than my amp --- so not sure if the input specs are the same? I assume they are.


41w37UMyZSL.jpg
 
varmint said:
Slightly OT, but does anyone have any experience trying to use a 12v step-up to power these amps off the 6vTx power? I've been thinking about using one, but probably won't if I need to strap on a separate battery.
I have seen set ups where they mounted the amp under the controller and added a 12 V battery next to it. Have not seen where anyone used anything else. My version has a 6 volt adapter and will run off a 5 volt 12,000 MAh phone charger in my pocket.
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MadMitch88 said:
I've been using this same amp (slightly newer version) for over a month without any attenuator and it works fine.

I believe the RE-700 maxes out at 100mW output and the Sunhans 2.4 GHz amp can accept up to 100mW (20 dBm) input as per it's spec sheet.

I have the Sunhans Model SH-2500 (shown below) and your photo looks different than my amp --- so not sure if the input specs are the same? I assume they are.
About the same specs. Mine will run on 5 volts. Most discussions I have found state the RE-700 just may overload the amp and actually cause less FPV distance. As with any electronic device, YMMV.
 
Happyflyer said:
About the same specs. Mine will run on 5 volts. Most discussions I have found state the RE-700 just may overload the amp and actually cause less FPV distance. As with any electronic device, YMMV.

I've had my P2V+ out to 2.5 miles before I lost control signal --- so I'm pretty happy with FPV distance using this amp (using a half-dome antenna from FPVLR.com on the output side of it as well as bird-side pinwheel antennas) :p The bird-side pinwheels make a HUGE difference --- probably tripled max. range compared to the stock FPV antennas on the Phantom.

However, I'm a firm believer in empirical evidence --- so if you have the patience, just make a few runs with and without the attenuator on the same day on the same flight path and see what kind of results you get. That's the only to know for sure if the attenuator makes an appreciable difference in max. FPV distance. :)
 
Yes, I have all the antennas for my P2V from FPVLR, but have not been able to test yet. Waiting for longer cables for the camera. Before the antennas on the quad I reached 8,000 feet and still had control. But I had to fly sideways to keep FPV. That was only at 425 feet up. So darn cold here now that one does not want to fly much. Cables will be here Tuesday so if wind and rain/snow stay away I may be able to try with all the antennas working. Will try with and w/o amp and see.
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Since you mentioned you have the clover antennas, beware, I lost one of my 5.8 off the quad. Going to use loc-tight and cable ties to make sure they stay on. Too expensive to loose those antennas.
 
Happyflyer said:
Yes, I have all the antennas for my P2V from FPVLR, but have not been able to test yet. Waiting for longer cables for the camera. Before the antennas on the quad I reached 8,000 feet and still had control. But I had to fly sideways to keep FPV. That was only at 425 feet up. So darn cold here now that one does not want to fly much. Cables will be here Tuesday so if wind and rain/snow stay away I may be able to try with all the antennas working. Will try with and w/o amp and see.
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Since you mentioned you have the clover antennas, beware, I lost one of my 5.8 off the quad. Going to use loc-tight and cable ties to make sure they stay on. Too expensive to loose those antennas.

I use a couple wrappings of electrical tape around the connectors of both bird-side pinwheels to the landing gear. I don't see how they could fall off using that method, but I suppose nothing is impossible once that bird is up in the air and getting buffeted by the winds.

With the combo of Sunhans amp and bird-side pinwheels --- be prepared to send that puppy WAYYY out there in the cold Michigan atmosphere :D
 
Yup! :D
 
dirkclod said:
How high did ya have to go to get 2.5 ? I just have the TX mod's and had to be at 550 to 600 to get 1 mile and then I lost FPV so I brought it back .

I was at 400 ft. AGL when I hit the 2.5 mile mark --- but this flight was in Northeast Ohio where it's rather flat. I was in a rural area full of cornfields and devoid of tall trees, buildings, and WiFi interference so that helps, too! :D

Do yourself a favor and buy the bird-side 2.4 GHz pinwheel antennas from FPVLR.com and you'll be quite happy at the improved range (at moderate altitude). :p

The odd thing I've discovered in my long-range testing is that if I sit down (for comfort) and place the Tx on a picnic table I tend to lose signal at around 1.5 miles but if I stand up I can squeeze out another mile of range --- hard to believe that extra 2 or 3 ft. of altitude on my end can make that kind of impact. :eek:
 
varmint said:
Slightly OT, but does anyone have any experience trying to use a 12v step-up to power these amps off the 6vTx power? I've been thinking about using one, but probably won't if I need to strap on a separate battery.

I use a 10000mah power pack with one 12 volt output and 2 usb (2amp and 1amp) outputs. Think the usb outputs are 5 volt. Seems like it should be possible to run Tx from one of the usb outputs. Was going to try that but lost the idea until I read your post. If you can use rechargable nicads to power Tx at about 4.8 volts then 5 volt usb should be ok.

I run 2 amplifiers from my power pack (2.4ghz and 5.8ghz) and 1 usb to the extender. Uses about 25% of power pack capacity per three 15 minute flights.
 

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