External Power Amplifiers


#1

Hi,

I’m looking to extend the output power of the Myriad RF board to get a range. So, I’m looking for external PA. Can you recommend me the PA to get a 10m, 50m and 100m range.

Thanks


#2

Upp+++

That is what i need also.


#3

Hello,

Generally LMS6002D provides enough output power to cover a 10m range for most modulation schemes. As for 50m or more, you could use any of the PAs supplied by the likes of Skyworks:http://www.skyworksinc.com/Products_FEMs.aspx They have a wide range of PAs for different modulation schemes and/or frequencies.


#4

I am also looking for an external PA, but something a bit power powerful. 25 Watts (44 dBm) or so. I’d like to have something rather broadband. Any suggestions?


#5

Does anyone know anything about cheap Chinese broadband power amplifiers like this one?

5 MHz - 6 GHz range, 20 dB gain (max. output power 21 dBm), it seems really great. And costs less than $10! There are many more similar cheap Chinese amplifiers on eBay, but I couldn’t find any more technical details about them :-/


#6

@mikos Cheap usually means that it will have an generic MMIC on it with the part number sanded off. They do this to stop even cheaper lower quality clones. And it probably only has a few vias or even no vias at all between the ground planes. Or else it will be missing the second ground plane altogether. With high resolution photos of both sides of the board you can usually tell a lot about the build quality. If the photos are blurred or very low quality don’t buy it is a very good rule of thumb, for cheap.

If you were planning to use a PA as the last RX stage for some extremely weak signals be careful to add an attenuator, to bring signals levels well under the devices maximum (10dB or more under the maximum is a good safe level to aim for or below, to avoid damage) What is the Maximum RX input power (before damage)?
Antenna->(BPF)->LNA->Cable->PA->Attenuator->(BPF)->Receiver.
Its noise figure will be very bad, but as a very last amplifier stage the signal levels “should” be above it’s noise floor.

Or maybe just stick to the more traditional TX configuration of a PA:
Transmitter->BPF->PA->Cable->Antenna
And with a SDR Transmitter be sure to have the signal that you want to off centre well away from the DC spike. And have the DC spike well inside the attenuation band of your Band Pass Filter, so that you are not transmitting the DC spike.


#7

@mzs I have found also this one (seems exactly same) with much better pictures. But more detailed technical parameters are also missing (e.g. noise factor).

5 MHz - 6 GHz, 20 dB gain, max. 21 dBm … $9.56

What do you think? Maybe better options would be these two:

5 MHz - 4 GHz, 26 dB gain, max. 22 dBm, noise factor 1.1dB@1GHz … $15.48

1 MHz - 4 GHz, 20 dB gain, max. 20 dBm, noise factor 2dB@1.5GHz … $11.8

Which one would you choose? I like that second one goes down to 1 MHz, but first one has obviously better noise factor and gain. For TX on 868 MHz or 2.4 GHz and possibly also RX (on whole range).


#8

Cheap LNAs are good. But I am looking for PAs, around 45 dBm (50 watts) at UHF for ham radio use. Sure, I can use some generic ham amplifiers, but I was hoping to find something broadband and relatively cheap. I’d like 45 dBm, but could probably do with 40 dBm at HF, 37 at VHF and UHF, and 35 dBm at microwave.