TheRadioBoard

Forum for the homemade radio builder. Newbies and Experts and everyone else are welcome here!
It is currently Sun May 19, 2013 4:13 am

All times are UTC




Post new topic Reply to topic  [ 18 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Modern radio
PostPosted: Wed May 16, 2012 8:25 am 
Offline
Site Admin
User avatar

Joined: Sat Jun 06, 2009 6:58 pm
Posts: 2525
Location: South Florida
EDN, a professional publication, recently ran an article by Doug Grant, K1DG, telling non-ham engineers about the current state of the art in non-commercial HF radio equipment.

http://www.edn.com/article/521690-High_performance_HF_transceiver_design_A_ham_s_perspective.php?cid=Newsletter+-+EDN+Fun+Friday

73,

_________________
Image
http://kr1s.kearman.com/
http://qrp.kearman.com/


Top
 Profile  
 
 Post subject:
PostPosted: Wed May 16, 2012 11:50 pm 
Offline

Joined: Sun May 23, 2010 7:18 pm
Posts: 165
Location: Raleigh, NC USA
Interesting article.

It is kind of surprising that HAM transceiver applications have resisted the wireless trend towards super integration. I mean that we have AM, FM, cellular, WiFi, Bluetooth, etc. one or two chip transceivers/receivers, so why not a one or two chip ham transceiver?

I'm guessing that selectivity of HF bands and linearity are pretty big nuts to crack.

Thanks

_________________
Überdyne: An extraordinary small force.
Kevin


Top
 Profile  
 
 Post subject:
PostPosted: Thu May 17, 2012 2:10 am 
Offline
Site Admin
User avatar

Joined: Sat Jun 06, 2009 6:58 pm
Posts: 2525
Location: South Florida
As the author mentions, you need high volume to justify development of application-specific ICs (ASICs). We need more hams with $$$. :)

73,

_________________
Image
http://kr1s.kearman.com/
http://qrp.kearman.com/


Top
 Profile  
 
 Post subject:
PostPosted: Thu May 17, 2012 9:37 am 
Offline

Joined: Sun Apr 08, 2007 8:02 am
Posts: 1196
Location: Saskatoon
KR1S wrote:
...We need more hams with $$$...


Probably the last thing we need. Real innovation came from the dirt poor hams with some clever ideas.

Yeah, I know you were just joking.


Top
 Profile  
 
 Post subject:
PostPosted: Thu May 17, 2012 9:56 am 
Offline
Site Admin
User avatar

Joined: Sat Jun 06, 2009 6:58 pm
Posts: 2525
Location: South Florida
Bob Weaver wrote:
KR1S wrote:
...We need more hams with $$$...


Probably the last thing we need. Real innovation came from the dirt poor hams with some clever ideas.

Yeah, I know you were just joking.

Well, no, I wasn't. I think the future lies in digital, as much as we prefer analog. But there has to be enough demand to amortize development and manufacture of task-specific ICs. Developing DSP requires some processor power, but PCs are getting pretty cheap. My 3-GHz quad-core / 5 GB / 750 GB system cost me less than the 1.4-GHz / 768 MB / 40 GB system I built in 2001. So SDR is a cheap way in for newcomers, at modest hardware cost. Even the dirt poor have PCs these days.

Check out the Elecraft KX3 (not the K3 mentioned in the article), a portable radio with built-in digimodes that doesn't require a PC, 160-6 M, 10 W, fits in your hand. You can bet there's a lot of DSP in that little box. You don't get to solder this one together, either. The price almost put me into cardiac arrest, but it's a slick little gadget.

AFAIK, none of the the people (PhDs all) who developed the SiLabs chips as used in Tecsun and Grundig portables, is a ham. Which goes a ways to explaining why those radios don't have BFOs. Getting all the astronauts licensed was nice, but we really need to get ham radio back into the mainstream communications industry.

73,

_________________
Image
http://kr1s.kearman.com/
http://qrp.kearman.com/


Top
 Profile  
 
 Post subject:
PostPosted: Fri May 18, 2012 5:25 pm 
Offline
User avatar

Joined: Thu Jul 24, 2008 6:07 pm
Posts: 231
Location: Nevada
KR1S wrote:
Well, no, I wasn't. I think the future lies in digital, as much as we prefer analog. But there has to be enough demand to amortize development and manufacture of task-specific ICs. Developing DSP requires some processor power, but PCs are getting pretty cheap.

Check out the Elecraft KX3 (not the K3 mentioned in the article), a portable radio with built-in digimodes that doesn't require a PC, 160-6 M, 10 W, fits in your hand. You can bet there's a lot of DSP in that little box. You don't get to solder this one together, either. The price almost put me into cardiac arrest, but it's a slick little gadget.


There is a slippery slope to greater development of digital radios with application specific integrated circuitry ... ASIC. Think of all the hams that are still able to find old boatanchors, and fix them up and put them back into service ... because parts can be found ... or fabricated / substituted. Then think about the radios that are less than 15 years old that already can not be serviced due to a lack of ASIC's ... or even some esoteric part - like a miniaturized rotary encoder.

I'm all in favor of progress, and development of new technology. But I would like to see more radios and other devices that use "generic" components to do great things ... I am interested in the SDR's as well. But I would like to see low cost versions that can be controlled by any commonly available PC, and use mostly non custom chips to construct. The KX3 is a very elegant radio, and I applaud the developers ... but, will you be able to find parts for it in 20 ... or even 10 years ???

Just my 2 cents ... :?

Tony


Top
 Profile  
 
 Post subject:
PostPosted: Fri May 18, 2012 11:11 pm 
Offline
Site Admin
User avatar

Joined: Sat Jun 06, 2009 6:58 pm
Posts: 2525
Location: South Florida
Night Flyer wrote:
There is a slippery slope to greater development of digital radios with application specific integrated circuitry ... ASIC. Think of all the hams that are still able to find old boatanchors, and fix them up and put them back into service ... because parts can be found ... or fabricated / substituted. Then think about the radios that are less than 15 years old that already can not be serviced due to a lack of ASIC's ... or even some esoteric part - like a miniaturized rotary encoder.

I highly recommend Clinton B. DeSoto's "200 Meters and Down," originally published in 1936, but still in print and sold by ARRL. Among other observations, DeSoto noted -- only a little more than two decades after he and Maxim founded ARRL -- that amateur radio had crossed a threshold. It was no longer the sole preserve of technical types; they had given way to operators, who used the technology without necessarily understanding it. This, more than 75 years ago!

People who fix up and perhaps use boatanchors (I see lots of photos of basements full of the things, sitting unused on miles of industrial shelving) are nostalgic, sentimental romantics. For casual ragchewing, a Drake 2B and a Ranger II will work fine. I had that setup on the air in the 90s. When I heard a DX station working split, however, it was back to the Icom. Ham radio has come a looong way since 1962. Sure, boat anchors will get you on the air, and a bicycle will get you down the street. If that's the limit of your interest, okay. But new techies are avoiding ham radio like the plague. There are about 600,000 hams in the U.S. According to Wikipedia, quoting ARRL in 2011, there are 2 million hams in the whole world. That number could be two orders of magnitude greater and still not compare with the 900 million Facebook users. (http://en.wikipedia.org/wiki/Amateur_radio#Licensing)

To use Facebook, you need some computer-operating ability. When I built my first computer in 1977, there were far more hams than people using computers. What's happened since? We have to face the turning tide. Rf technology is commonplace, and so are affordable, fast and efficient computers. Every one of the millions of cell phones and tablets is carrying radio and computer technology far more sophisticated than any ham rig.

The big deal in mobile communications now is Apps; software, not hardware. To survive, ham radio has to present communications modes that excite people, the way CW excited me 50 years ago. (CW would have excited me just as much if the equipment had been as easy to use as my KX1. A famous quote from Marshall McLuhan: "The medium is the message." Ie, not the hardware or even the content. Think about that when you're operating your ham station, or DXing with a homemade radio: 99% of the time it's not what you and the other ham say, or what the distant station is broadcasting, or even the equipment you're using; it's the medium itself that enthralls. In that exciting moment the hardware becomes transparent. Yes, you might not enjoy the communication as much with a modern radio, but that's more a criticism of the content than the hardware.)

Hardware today has to be simple to operate, so users can concentrate on using it. Plate Tuning, Loading and Drive Level controls won't cut it anymore. We didn't have all those controls on vintage rigs because they were cool, but only because we didn't yet know a better way. Using old radios brings back the thrill of the early discovery of the medium, the hardware acting as a mental aid to an emotional connection. But when that connection clicks in, you transcend the hardware and lock in to the medium. Newcomers to radio can never experience that thrill, when they can listen to foreign radio stations streamed on their iPads. They've already transcended hardware. Radio isn't exciting in and of itself anymore.

There always will be anachronists interested in regen receivers, steam engines and Renaissance fairs. But these are leisure activities that do little to drive progress. Yeah, a few young folks will go on from them to high tech, but remember, when we started playing with regens and crystal sets we were not that many years removed from when they were high tech. To stay within the moving scale of time, we all ought to be at least building up-converting, dual-conversion superhets. :wink:

The new keyboard modes don't interest me that much from an operating standpoint, but my late father had no use for cell phones and barely tolerated the VCR, though he took to using a PC with alacrity (fortunately I had an 800 number at work, so he could call me every time he invoked the BSOD :? ).

It's 1936 all over again, the new age of the user of technology, and anything that pushes usability is good, even if the hardware is built for obsolesence. The difference is, radio is now only one medium among many for communications, and software development. As with cell-phone apps, if there isn't a user base, no one is going to develop for it. Just my devalued 2 cents.

73,

_________________
Image
http://kr1s.kearman.com/
http://qrp.kearman.com/


Top
 Profile  
 
 Post subject:
PostPosted: Fri May 18, 2012 11:25 pm 
Offline

Joined: Sat Aug 18, 2007 8:52 pm
Posts: 1991
Location: Australia
A bit more than 2 cents worth. Insightful.

.................................


Top
 Profile  
 
 Post subject:
PostPosted: Fri May 18, 2012 11:54 pm 
Offline
User avatar

Joined: Thu Jul 24, 2008 6:07 pm
Posts: 231
Location: Nevada
KR1S wrote:
I highly recommend Clinton B. DeSoto's "200 Meters and Down," originally published in 1936, but still in print and sold by ARRL. Among other observations, DeSoto noted -- only a little more than two decades after he and Maxim founded ARRL -- that amateur radio had crossed a threshold. It was no longer the sole preserve of technical types; they had given way to operators, who used the technology without necessarily understanding it. This, more than 75 years ago!


I basically agree Jim, ham radio is as exciting to "non-tech's" as "tech's" ... but it is historically not just a hobby for operators ... otherwise why do we have licensing and testing ?? Those who only want to operate can be SWL's, CB'rs, or even just cell phone super-users. The same dual level existance exists in the computer world. While most happily use the computer for more things than I can imagine, there are the techies who constantly hack, program, revise, and extend what the computer can do ... and those folks are usually the fountain from which new "stuff" comes.

So should be ham radio. Hams don't necessarily sit around and wait for the next new thing ... they invent it ... and that level of participation is what makes ham radio, ham radio. As long as the basic bits of technology that go into making the hardware we use stays in the realm of what we can mold into new ideas, ham radio will be interesting and challenging to folks like me. As soon as it is only a hobby where you basically only operate devices you can not tweak, change, or get under the hood of, then the hobby will have all the lustre of the cell phone. So, let's hope the hobby continues to have something for everybody ... the operators AND the techies.

And now I've spent my last cent :oops:

Cheers,

Tony, KD7TOG

... -.-


Top
 Profile  
 
 Post subject:
PostPosted: Sat May 19, 2012 1:36 am 
Offline
Site Admin
User avatar

Joined: Sat Jun 06, 2009 6:58 pm
Posts: 2525
Location: South Florida
Night Flyer wrote:
And now I've spent my last cent

No, this is interesting! I think hardware has pretty much gone as far as it can go. The future of radio hardware is ASICs, because they make for cheap radios, and software. There isn't much new to discover about mixers, oscillators and amplifiers, which are all you need to make a radio. Where we can do cool stuff is software. So the guy hacking together a radio from discrete parts is a dinosaur. You design a chip and move on to defining its functionality with code. No hardware changes needed. We have to accept that we hardware-oriented guys are a dying breed. You aren't going to design and build a chip at home, but you can write code to make it do new and maybe exciting things.

Back in the day I worked for Gerber Scientific, Inc. All they make now is sign-making machines, and they're owned by a Chinese venture-capital group! When I was there they were struggling to move from hard-wired logic to software, and it was a battle, because Joseph Gerber, the founder, called programmers "code pushers." I watched the battle and decided I wouldn't let that happen to me. I see the same battle unfolding in hobby radio now. I don't want to be a code pusher, but I accept defeat! :cry:

73,

_________________
Image
http://kr1s.kearman.com/
http://qrp.kearman.com/


Top
 Profile  
 
 Post subject:
PostPosted: Sat May 19, 2012 7:42 am 
Offline

Joined: Sun Apr 08, 2007 8:02 am
Posts: 1196
Location: Saskatoon
My previous comment was somewhat flippant, and I should clarify. It was based on what I personally find interesting in the hobby, and that is doing as much as possible with as little as possible. However, I realize that what interests me doesn't necessary interest others, and the hobby has to accomodate everyone, including those who are happy to pay money to buy equipment that's ready to go. So, maybe it wouldn't be such a bad thing to have a few people with lots of $$$, if it keeps things alive.

BTW, speaking of code pushers. That's pretty much what I do for a living these days: industrial control systems, all of which use programmable controllers. So, it's a matter of plugging together off the shelf controllers and I/O modules, then lots of programming. So now the hardware design is about 5% of the work, and the other 95% is coding.


Top
 Profile  
 
 Post subject:
PostPosted: Sat May 19, 2012 8:44 am 
Offline
Site Admin
User avatar

Joined: Sat Jun 06, 2009 6:58 pm
Posts: 2525
Location: South Florida
Bob Weaver wrote:
BTW, speaking of code pushers. That's pretty much what I do for a living these days: industrial control systems, all of which use programmable controllers. So, it's a matter of plugging together off the shelf controllers and I/O modules, then lots of programming. So now the hardware design is about 5% of the work, and the other 95% is coding.

It was interesting to watch the transition at GSI. We made high-end pen and photo plotters, which took Gerber-format code as input, but were dumb. In 1979 we came out with the first PC-board layout system, the PC-800. It had a big digitizer plugged into an HP mini with a 5-1/4 inch floppy (later two 5-1/4 inch floppies!), that drove a photoplotter, for which GSI owned the patents. It was a big seller, and finally convinced management that software was the future. You paid for a software maintanence contract, so the bucks kept rolling in after the initial sale. Good-bye sticky black tape. Now, of course, we have auto-routing software (GSI tried to do that but they never figured it out to Marketing's satisfaction) that runs on a PC, and all those PC-board designers are obsolete.

One of my last high-tech jobs was for a company that made high-power UHF TV transmitters. Most of the rf engineers had no knowledge of early radio technology, because they didn't have to know it. The transmitters were built of mostly discrete components (bipolar transistors up to the PA) and they understood networks for combining driver modules, biasing, heat-sinking, and all the stuff they had to know. They wouldn't have known a regen from a refrigerator. You don't have to start out building crystal sets and stuff to make it as an engineer.

Photography and cinema, two other interests, went the same way. I remember the fun of holding up a piece of film and seeing the frames in miniature. It was magic. Now anyone with a few thousand bucks for a DSLR and Photoshop, and an eye for composition, can be a great photographer or videographer, without ever inhaling developer and hypo fumes, or learning to use a film splicer.

Like blacksmithing, the skills of our youth are becoming obsolete. Like logic designers now, future radio designers will pick a selection of chips from a databook, write some code, and never have to think about what's going on inside the dies. The up-side is, radios will become less expensive, or at least not get more expensive (calculate the cost of a Collins S-Line in 2012 dollars), making radio more inviting to the dirt poor! :D

73,

_________________
Image
http://kr1s.kearman.com/
http://qrp.kearman.com/


Top
 Profile  
 
 Post subject:
PostPosted: Sat May 19, 2012 11:41 am 
Offline

Joined: Sun Feb 28, 2010 2:12 pm
Posts: 1021
KR1S wrote:
Radio isn't exciting in and of itself anymore. There always will be anachronists interested in regen receivers, steam engines and Renaissance fairs. But these are leisure activities that do little to drive progress.

I feel that there are two separate issues here: radio for radio's sake, and radio as a wellspring for technical or societal progress. To me amateur radio is, as the name suggests, about an affinity for the medium of radio itself, because the natural phenomena themselves are deserving of study. I would like to believe that future generations will continue to be interested in understanding and controlling fundamental physical phenomena like electromagnetic radiation.

As far as driving progress, if no progress is to be had by hobbyists at the analog radio level, and future progress lies mainly or only in software, then that represents a shift away from the direct maniuplation of radio frequency energy and a shift towards manipulating man-made software or hardware abstractions. I can agree that most opportunities for immediately-usable progress lie here, but I think there will always be people who want to look behind the curtain and get in touch with Nature herself, rather than working with someone else's abstractions - no matter how handy those abstractions may be.

I like the following Ellen Ullman article (a bit old, but still surprisingly fresh) for its expositon of the desire to peel back layers of other peoples' abstractions: http://images.salon.com/21st/feature/19 ... ature.html
Quote:
Two hours later, I was stripping down the system. Layer by layer it fell away. Off came Windows NT 3.51; off came a wayward co-installation of Windows 95 where it overlaid DOS. I said goodbye to video and sound; goodbye wallpaper; goodbye fonts and colors and styles; goodbye windows and icons and menus and buttons and dialogs. All the lovely graphical skins turned to so much bitwise detritus. It had the feel of Keir Dullea turning off the keys to HAL's memory core in the film "2001," each keyturn removing a "higher" function, HAL's voice all the while descending into mawkish, babyish pleading. Except that I had the sense that I was performing an exactly opposite process: I was making my system not dumber but smarter. For now everything on the system would be something put there by me, and in the end the system itself would be cleaner, clearer, more knowable -- everything I associate with the idea of "intelligent."


Top
 Profile  
 
 Post subject:
PostPosted: Sat May 19, 2012 3:54 pm 
Offline

Joined: Thu Mar 12, 2009 4:09 pm
Posts: 918
Location: Sonoma County, CA
This is an interesting thread and I agree with most of it.

Quote:
Like logic designers now, future radio designers will pick a selection of chips from a databook,


I don't think so. From my days in the analog and switch-mode ASIC business at Siliconix, I would say that ASIC is still a useful idea. The sharp designers will go to the chip folks and describe the functions of an ASIC that combines features in new ways and interfaces with the software. We built ASIC for hard-drives, for example, starting with a simple H-Bridge, then incorporating gate drive, then servo control, etc.

This makes for cheaper, more manufacturable products, but means that the volumes have to be high. Even in the 1990s, we wouldn't get interested in a custom chip for anything less than a few hundred thousand pieces.

If the designer picks a "radio sub-system IC" from a databook, you can be sure that some other company (competitor) paid at least part of the cost of that chip design and it's already a few years old. That's a viable route if you need a few thousand chips, I guess, but you will never be "leading edge" if you pick chips out of the catalog.

We had about 20 hams at Siliconix in the early 90s. Now Siliconix is part of Vishay and many of the analog products are being phased out. Not a lot of profit in making TO-92 JFETs any more!

Rich

_________________
Homebrew Radio ex-Silicon Valley


Top
 Profile  
 
 Post subject:
PostPosted: Sat May 19, 2012 5:54 pm 
Offline

Joined: Sun May 23, 2010 7:18 pm
Posts: 165
Location: Raleigh, NC USA
This an interesting thread for me, because I'm caught in the middle.

My career is in radio ASICs, but I started out as a HAM, technician and then ASIC design engineer.

When I started as a HAM in the 80s everyone was either talking about computers (PCs and packet radio) on 2m or trash talking on 80m. No one was talking about radio technology and science which is why I was interested in HAM radio in the first place. So, I gave up as an operator and just focused on learning all I can about radios for my job.

I was invigorated a few years ago when I decided to look into crystal radios as a hobby to learn more about the fundamentals of radios. I have spent most of my hobby time understanding crystal radio well enough to design a well performing set using a multi-turn loop antenna. I have learned a lot and I'm still working on my set.

So, my point of view is biased. The present and future of consumer radio/wireless is ASICs, and so goes a part of the hobby. But a big part of the hobby is learning and practicing radio technology, and using ASICs does not completely satisfy our desire to build, learn and play and start all over again.

I'm just happy sites like this, Ben Tonque's, Peebles, Rap'n Tap, Gollum, etc.. are around to share a wealth of knowledge about a hobby that has little to do with programming. Although, a little programming can be useful for designing coils and antennas.

BTW
There is a lot of innovation from academia and industry in integrated radio front-end designs. Much of the focus these days in improving the dynamic range of direct conversion receivers to reduce the selectivity requirements for RF filters.

73s
KJ4PD

_________________
Überdyne: An extraordinary small force.
Kevin


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 18 posts ]  Go to page 1, 2  Next

All times are UTC


Who is online

Users browsing this forum: No registered users and 0 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group