HIgh End Flex Users Disappointed by APD limited to 8600 Hardware

Ken D'Alessandro

Many Flex users have been patiently waiting for Flex to implement Adaptive Pre-Distortion (APD). The announcement by Flex at 2024 Hamvention that APD will be available in the 8600 series radios is considered by those I have spoken with as a betrayal by Flex of its 6000 series high end users who feel that we have long been promised that APD would be eventually introduced at some point with the implication that it would be made available on current Flex hardware. To now find out that we have to buy new hardware to get this feature is quite an unpleasant surprise as it seems that APD could have been implemented in a SmartSDR version for the 6000 series radios. I would not have bought my 6600 less than a year ago if I had known that I would have to buy an 8600 to get APD as a feature with my PGXL.

Erik Carling EI4KF

Find out how? That is contrary to the Flex announcement. Whilst certainty is not guaranteed, they clearly state their intention to provide ADP on 6000 series radios at a later date with a hardware accessory assuming that is it cost effective. So not cast in stone and maybe with patience you will get a nice surprise. We are most assuredly not at the situation 'have to buy an 8600 to get ADP'.

Ken D'Alessandro

Found out by reading FlexRadio Media Press Release email sent on 17 May announcing the 8600 series.

Mike VE3CKO

The adapter box surely can be done with a Pi but that would be too easy to reverse engineer so sounds like they will develop and build a Pi-like stand-alone box that would likely interface to the serial port on the 6xxx. Guess what they mean by cost effective, is to manufacture it and see what they would have to sell it for. They still have to determine of course which 6xxx models would be able to handle what APD would demand from the CPU. My thoughts it the "adapter" would be doing all the heavy lifting, spitting out data that SmartSDR would need do what it needs to do. What I find interesting is the two versions of APD, static (manual) and adaptive.

This has been thought out quite thoroughly so reading between the lines, this may be a method to separate, existing 6000 series users and those buying the new 8000 series. I would hope they would implement and make available at least the static APD adapter for the 6000 series , you want adaptive ADP buy an 8000 series. This would both satisfy existing user base and not deter from new sales.

Erika - KØDD

Ive been watching every video and reading every thing that pops up in regard to the new radios and what updates they plan for the older radios. I personally believe features beyond the capability of older hardware should be left for new hardware. They've already stated the older gear needs more processor power for apd Seems like the loudest critics of what flex it doing and in what order are the peeps thinking APD is an absolute necessity for any radio... oh ANAN has it. Well I've never heard an ANAN on the air that I've even liked how they sounded. I have personal needs for ssb dxing.... Ive ran my 6500s in AM groups anywhere from 6 to 10 khz bandwidth and get nothing but complements on how they sound... whether 25w carrier or into an amp... Do you guys screaming about APD even know what a radio with that feature even sounds like? As loud as the drum is getting beaten I'd think the operators of one of those radios would be gifted with golden crowns and a beautiull shining light would light on the front panel of someone receiving them. Im a DXer... I have to have number one feature... the ability to hear a dx station I desire to work. I need to be able to filter out absolutely every interfering station. Give me whats important. A receiver that receives what i need to hear. Then a clean powerful FT8 or CW and an excellently processed SSB transmitter that gives my nice girl voice the sound of a goddess capable of busting wine glasses, windows and pileups... you'd be surprised how potent my vintage 2013 and 2016 6500s can become with the correct settings on the internal EQ and a quality microphone on it can sound. K0DD

Trucker

Erika, APD is a method to clean up a transmitted signal's IMD. It does not and should not effect the transmit audio. If it is, there is something else going on with the station's audio chain. I consistently receive unsolicited compliments on my transmit audio running Thetis and Pure Signal ( aka: Adaptive Pre-Destortion) using my Anan 8000DLE. When problems like you describe occur, it is very likely not APD being the source of the problem. It's more likely sitting between the chair and microphone.

James

WD5GWY

AA1SS

So they promised APD with the 6000 series . . . vaporware . . . As it never happened. Now again they are promising APD with the 8000 series . . . Same old story to sell radios. They need to work on the software and fix some of the bugs like poor ANF, NB etc. and stop making promises they don't keep..

K5XH

A personal observation of what APD can do….

I have a very experienced local ham friend that has a lot of experience with both Flex (6700 and 6600) and the ANAN. I can tell immediately which radio he is using by looking at his signal on my 6600. The ANAN shows nothing outside the transmit bandpass. I hope that Flex can achieve the same results that the ANAN is capable of.

K5XH

Mike-VA3MW

More details in this chat:

https://community.flexradio.com/discussion/8030150/static-vs-adapative-pure-signal-vs-adaptive-pre-distortion

G2YTpeter

I have just got my 8600 up and running (upgraded from 6400M). I was not really expecting to see it with APD at this stage, but I certainly hope it comes soon… As for Erika's comment about "how it sounds like"… this seems to demonstrate a lack of understanding about what APD is and why use it. It should sound no different at all… just make a significant cleaning up of the TX bandwidth.

Steve-N5AC

When we announced the FLEX-8000 series at Hamvention, we discussed APD and said that our plan was to come out with APD on the FLEX-8000 first. We added additional processing power and an internal sampler for this purpose. It's technically possible to add this to a FLEX-6000 series radio with some external hardware. But to do so, we have to amortize the engineering cost across the number of a FLEX-6000 APD units that we believe we could sell. Customers will weigh this against the cost to upgrade to a FLEX-8000 so this would have to be a compelling difference. For example, if the cost to upgrade was $1,000 but the APD option was $700, customers would say "well for another $300 I can have a new radio with a warranty… why would I buy the APD addition?" So this is some calculus (or rather 5th grade math) that we'll have to consider after we release APD on the FLEX-8000 Series.

We also need to weigh the engineering work for a FLEX-6000 APD module against other work we could do and the benefits to customers of that work (a.k.a. "opportunity cost").

This answer is not a "No, we're not going to do that." Rather it simply states clearly that there are trade-offs and that we have not yet decided how we will proceed. We expect to decide after we release it for the FLEX-8000 Series. We're all aware that this is an unsatisfying answer. I dislike conveying it as much as you dislike hearing it. We want to provide it, but we're holding off on any commitment until we can do the 5th grade math.

Trucker

Steve, Thanks for the informative post. I have read in the past that the 6000 series radios already have the internal connections ( feedback sampler?) for APD. And that it has been working successfully on a test 6000 radio. I know that without an external connection to sample the output from an amplifier, that it would not be as effective with a radio and amplifier combination. But, not all of us use a amplifier. So, even though we couldn't use APD with a feedback signal from an amplifier, some of us still would like to have the cleanest signal possible. APD would give us that.

Maybe, that would give a better indication of those that are willing to pay for an external sampler for use with a amplifier. Rather than just saying if you want APD you need to purchase a 8000 radio. Some of us have to stick with our 6000 radios for various reasons. But, would still like to have features we were led to believe would be coming to the 6000 radios because the radios already had the necessary connections made internally.

James

WD5GWY

Mike-VA3MW

Hi James

There is no Sampler in the 6000 series radio. If there was, we would not have to consider building the outboard sampler.

I believe you had heard that we had tested APD on a 6000, but that was completed with some external test hardware.

As Steve said, we need to finish the grade 5 math.

Trucker

Mike, what I read was from Gerald Youngblood, that the 6000 radios already had the internal connections made to provide the necessary feedback signal INTERNALLY for APD to work in the radio itself. He did not say that an external feedback connection existed to get a sample signal from an EXTERNAL amplifier. There was even a follow-up comment made that even though the connections were there, and in place, that there wasn't enough demand from the customer base to make APD a priority. In other words, the radios themselves can do APD. There are some of us that don't use an amplifier, but still we would like to have the cleanest signal possible. Adding the code to the 6000 radios would provide that. My final thought is, is Flex Radio only going to provide updates for the 6000 radios that fix problems? And will they offer new enhancements ( features and fixes for existing features that need improvement) or, is the 6000 series EOL from a software/feature perspective? Maybe, someone like Steven Hicks, or the CEO himself would be willing to comment on this subject.

James

WD5GWY

Mike-VA3MW

James

We have had this discussion before. Yes, that is what was to have happened in the construction of those radios and if we were still able to do it, we would offer it.

However, and confirmed by Steve a long time ago, it isn't possible as the required hardware configuration is not there.

I am not at liberty to say exactly why (and, I know why) as it is above my pay grade. If Steve wishes to share the history on why it is not possible he is more than welcome to.

Any new software features may only appear on the 8000 series, but it depends on the required computer horsepower on the CPU and/or FPGA. There will be a point when new features may not be available at all for the 6000 series for that reason. The product management group (of which I am part of) considers many key things before making it to the next phase. Those are: cost to develop, economic feasibility, the impact to the user base (lots of customers of a small amount of customers), and, if it will sell more radios. All of which roll up into the economic value.

BTW, if you ever want to drive a development engineer crazy, just start a sentence with "with some simple programming". Then take a step back and duck!

Trucker

"BTW, if you ever want to drive a development engineer crazy, just start a sentence with "with some simple programming". Then take a step back and duck!"

It's not much different than a dispatcher telling a truck driver " it's only a few inches on the map. " So,why,can't you be there tomorrow if you leave this evening???

So,yes from that perspective, I understand.

James

WD5GWY