'Pure Signal'

Peter Bentley

Does anyone have any news about the inclusion of 'Pure Signal' in a future update of SmartSDR ??

Martin AA6E

At Dayton, I recall that Flex made a passing reference to adaptive predistortion being on their development agenda, but I did not hear a target date.

Steve K9ZW

Believe there was mention of Adaptive Predistortion in conjunction with the FRS/4o3a Power Genius amplifier. 

Would seem to make sense as a largely Firmware/Hardware feature.

73

Steve K9ZW

Peter Bentley

Thank you Martin and Steve

G4BIM

John-K3MA

I sure hope that the resulting functionality is amplifier independent rather than tied in to one specific amplifier.

I believe the functionality if more software based aside from getting a sample of the transmitted TX signal.

Gerald-K5SDR

The amplifier will have a feedback tap from its output that will connect to a FLEX-6000. APD is software. It will not be called Pure Signal.

Paul Christensen, W9AC

Gerald,

The Flex APD (FlexSignal?) RF will route to a Rx ANT port on the 6500/6700 and ANT 2 on the 6300?  If so, then APD will not be limited to the Power Genius amp? 

Or <gulp> (and to K3MA's point), will Flex's APD software be looking for a pilot signal or marker generated by the amp that it will only work with Power Genius?     

Paul, W9AC

Roy Laufer

Will this feature be tied to the 403A Linear, or will it be able to be implemented in other third party linear amplifiers (if not initally, then at some later point)?

John-K3MA

I have run a couple of Anan's so I am familiar with the hook-up they use.  I think from Gerald's statement the 4O3R amp will provide a post amp feedback signal which the APD routine will use to make adjustment to the Flex transmit signal to improve the IMD.  Ideally to correct the entire system that feedback signal needs to come from the output of the RF amp and in most installation requires the addition of a coupler that provides the signal back to the Flex at a much reduced level.  From above this coupler circuit would be built into the 4O3R amp and for other amps a coupler would need to be purchased and installed after the amp.  A popular one is sold by AC2IQ.

Paul Christensen, W9AC

John,

All true, but a manufacturer could potentially limit APD for use with only its own branded amplifier.  For example, it could require a coded data handshake between Ethernet ports (between the amp and transceiver), or a low-level, narrow QPSK data carrier could be inserted into the RF output.  The transceiver's APD algorithm would look for that data and determine if the RF is being generated by its branded amp. 

This would allow a manufacturer to generate sales for one's own amplifier product line.  IOW, want APD? Sure, but you'll need to purchase our amp. 

Paul, W9AC 

   

Joe WD5Y

I sure hope this is not the case here because I plan to implement pure signal into my station (6500) with my present LDMOS amp. Sure would like to know what the pure signal hardware input into the 6000 is? 73's Joe WD5Y

Roy Laufer

A company could pull a "Keurig" and rig the system to require the purchase of a proprietary linear amplifier, but I think that this would awful for that business in the long run.

Sony used to be famous for their endless number of incompatible, overpriced proprietary connectors and take a good look at their financial shape.

You can introduce the feature for your own branded linear first with hopes to get it working for the 80% of Hams that already bought a linear amplifier, but announcing "it's my way, or the highway" will drive a lot of customers onto the highway.

Bill -VA3WTB

There is a guy now who may be marketing a stand alone product that will work on some radio's. He is running pure signal on his Flex now. He says.

Mike VE3CKO

Let's call it what it is, Adaptive Pre-Distortion (APD) as Gerald clearly pointed out, it is not pure signal, that is a competitors' term. So now that is out of the way, makes no sense for Flex to begin to dictate, "use our amp only", so let's not speculate with fairy tales. Makes perfect sense what John said, Flex would produce a coupler that would take the RF out from any amp and feed it appropriately to the 6000 series radio.

Bill -VA3WTB

That is right Mike. so any amp with a feed back tap should work. The Flex amp will be simply fitted with one.

Peter Bentley

Pure signal or Pre distortion. A process which further improves the quality of what is already a very 'clean' signal from the 6000 series. I think we are all singing from the same hymn sheet.

Can I please direct the following questions to Gerald K5SDR, and a simple yes or no answer will be sufficient.

Is the current Flex Radio 6700 capable of running a pure signal type mode with only a change to the current version of the SmartSDR software.

If the answer is no, will it be able to do this with the addition of a coupler type device available from FlexRadio and a change to the software.

Thank you

G4BIM

Gerald-K5SDR

The answer is yes it is only software for the FLEX-6700 and FLEX-6500 since both have an internal feedback tap from the power bridge.  

Roy Laufer

Will one of the 6700's RCVR inputs be dedicated to this function when a linear amplifier is involved, or is there some other means for the feedback signal to be obtained?

Gerald-K5SDR

It will not be limited to our amplifier.  An external coupler will be required for other amps.   Internal isolation inside the radio is critical to proper operation on all bands.  Our radios have better than -80 dBc TX to RX isolation on 6m, which is worst case.  

Gerald-K5SDR

When barefoot, it will not consume any inputs because the feedback is internal to the radio..  For an amplifier, you will have to connect the feedback to either the transverter port or a receiver input port.

Charles - K5UA

Thanks Gerald, was wondering how it would get to the 6500 from the amp. Thanks for putting it on the future enhancement list. Lookin forward to it.

Peter Bentley

Thank you Gerald, I am sure all 6500 and 6700 owners will be pleased to hear that.

Kind regards

G4BIM