I thought an individual ham in the USA could import  a non type accepted piece of equipment for personal use?

I see Ebay USA is full of export CB radios and illegal  RM Italy amplifiers. These illegal importers are doing a roaring trade with technical deficit disorder hams. What about all the garbage 2 meter HT radios from China?

The FCC is a toothless tiger against  all these small importers and seem to only pursue the celebrity companies for publicity. The same thing is occurring  in Europe. The market is getting flooded with equipment that fails all European EMC laws and all the importers have to do is produce a fraudulent certificate from the Chinese that says it meets standards. We all know that the Chinese manufacturers are making a mockery of our laws yet our authorities will hand out hefty penalties to any European based companies who break these laws. All double standards, the law is truly an ass  in this area.

Hi M Sarkaria

Do you have 2 tone  IMD data for the other bands? If you do have this data can you post it some time in the future? I am interested to see how the IMD performance holds up on all other bands.

Dont forget the venerable Drake L4B.

You can beef it up very easily. Just change the power supply capacitors and change the blower for an external big blower. If you want QRO just build a new external power supply. I would not bother.  It will do a 1kw  for 48 hours  with ham duty cycle. Just add 2 big muffin fans on the top of the cabinet and away you go.

The L4B is built like  a tank compared to the TL922 which is a flaky amplifier without upgrades, the parts are all marginal in the TL922. The Drakes RF deck is airy compared to the swiss watch engineering and cramming on the TL922. Lots of space to do things on the L4B's deck.

You can even put the L4B temporarily on 160 meters by just padding the load temporarily and using the 80 meter position. I have seen other hams use 2 X  3cx1200s in a L4B, this was done when 3cx1200's were cheap. This is an exercise in stupidity of course.

I will take a L4B over a  SB220 or TL922 any day. The only problem is the prices that the L4B is fetching is getting ridiculous.  I have a L4B deck on every ham band, all nine bands with a switch matrix. I dont need a solid state amp!

Agreed 100% with your comments. Its a technique thats rarely used today and  subject that is poorly understood.  I mostly use the resonant choke technique on screen supplies  for  voltages upto 1500 volts.  It works very well to the point where you dont need a screen regulator, even on SSB.

I just wanted to make sure that  someone does not remove the  resonance tuning capacitor from the choke! Many people made this mistake on the Collins 30S1.

mobile = k3

Its the radio with the worst ever ergonomics for base use. Everyone has their own opinions on this, this is my opinion.

I am waiting for the K4 maybe that will be a true home based radio.

I could however imagine a  K3 with dual P3's (one for spectrum and a separate P3  for  waterfall and rig info + TX monitoring)  new  front panel, 200 FET amplifier  and all in one box with a in built power.
What would even be better is a 10 inch touch screen K3 that combined the P3 and K3's designs. The modular concept should remain this way it would be easier to address any improvements or failures in various parts of the radio.

The K3 design has  lots of potential if all the marketing and packaging options are examined. The problem is that all the Elecrafters are more worried about fighting with the "elecraft haters" rather than making the product better with suggestion and product criticisms.

Very few products in the world can get it right with  the first release onto the market. It seems that the K3's design is trapped by being carved into rock by its owners and designers. The K3  could be rig for all people if some K3 owners opened their minds to the possibilities rather than just wanting to be  elecraft criticism attack dogs. Any criticism of the design has hardly effected the sales of the radio thats why its perplexing why so many owners react so negatively to the many suggestions and requests  for  and an improved K3.  Trying to bludgeon people into  believing that a radio is perfect when it is not does more marketing harm that good. We live in the information age not the brainwashed age.

Yaesu, Kenwood and Icom have been doing this for decades. If you sat down and studied their circuit diagrams you would  soon realize that the improvements in model X has become model Y with some minor changes. It was very rare to have a completely new clean slate design per new model. Why should elecraft designs be the exception and exempted from  this practice? It just makes good economic sense recycling old products into new exciting and improved products.

A totally ridiculous patent claim.

Its  ridiculous as the guy who first filed the patent for using a PC keyboard  that plugged into a ham transceiver.  This patent effectively blocked any transceiver from using a plug in keyboard.

This patent will prevent someone from releasing a SDR black box radio that will say for example use  IPAD for the interface.

This is like filing for patents on human genes and  DNA  in nature, totally  ridiculous when its been around for a million years. The patent system is well and truly broken.

Nobody minds the protection of genuine intellectual property but patenting a product  around the idea of  integrating concepts that already exists in the market is really beyond belief. We
see more and more manufacturers patenting things as ridiculous as a mounting bracket and the number of screws used.

All?

Some Henry amps used a resonant choke supply. The choke was tuned by a low value  capacitor across the choke. The 4K Ultra comes to mind as well as the Henry 8k Amp.

Just make sure your Henry amp does not use a resonant choke filter.  Changing the value of the capacitor will allow the plate voltage to soar to a high value, that could cause a lot of damage.

I have used a brute force choke supply by simply using the choke with two capacitors in the pie configuration. The improvement is not worth the trouble and weight..

These days its far easier adding a bank of snap electrolytics and  making sure  you have a adequate glitch R preferably with a fuse if the cap bank is rather large. Excessive joules can
cause a lot of damage.

If your amp does not use a resonant choke supply its worthwhile using a tuned choke as upgrade if you have all the parts. For a legal limit amplifier I would not bother with all the trouble because
whatever the amp  originally used for a filter bank is enough C or filtering.

TS-990S is another unremarkable radio that is using dinosaur concepts with bells and whistles.

I have read all the available material on the TS-990S and I read nothing that makes me excited about the radio.
While Kenwood has had a history of producing radios using  rather clean PA's, and  selecting linear PA devices, it excels at very little else.

The TS990S looks like its just going to be another pig in lipstick radio with the usual shortcomings.

Old technology
Birdies in the receiver
Poor transmitter design with the usual poor transmitter ALC. There is no reason whatsoever to have ALC in a modern transmitter as implemented by ham radio manufacturers.
A PA using excellent FETS that will not be optimized on all ham bands. Adaptive pre-distortion should have been the new standard.
Uncalibrated S-meter
A bandscope that wont have enough dynamic range  and controls to be a useful tool.
A radio with a 2 watt distorted 20% distortion audio amplifier.
Poor  receiver in band IMD.

Yes, its exciting that they have re-entered the ham radio  with a big radio. Projects like the HPSDR transceiver will  very shortly be  blowing all these expensive white elephant radios out of the water. Kenwood
and the other Japanese manufacturers really should get with the program and design radios using  the latest DDC/DUC architecture designs. This technology can deliver all the performance required  that does not require obsolete   dinosaur technology that will become obsolete when the Chinese manufacturers stop manufacturing the crummy parts.

There  is not one killer feature in the TS-990S design that can  be considered leading edge, its just another  new radio that will do little for the ham radio masses.
 Its a good radio for milking the baby boomers of their retirement savings. Nothing like a big box with knobs that does very little to help the average ham enjoy his hobby that cant be done with any available transceiver already available.

Excuse me I need to have a snooze!

DXENGINEERING are real professionals for international customers. You order something you know exactly what the freight is going to be. Try getting freight figures from some other companies, they take 1 week and then want to penalize
you for giving them money because of their laziness. Then they have all the weird  credit practices that would be fit for a 3rd world  country on mars. You have none of this from DXENGINEERING, they have excellent credit card practices and have no "foreign transaction" (robbery)BS practices.

 I have  ordered a ton of stuff from DXENGINEERING, and every piece was perfectly packed and arrived on time. They really have their act together. Its just such a pleasure dealing with professionals that understand how to do business internationally.DXENGINEERING is like the AMAZON.COM of the ham radio business. Really they way they conduct business I would not be surprised if they put everyone else out of the ham radio business. They really understand business, marketing and  the bottom line is that for such a small hobby they have the most professional customer service you will ever encounter.

If I was a manufacturer of anything ham radio, I would sell it through DXENGINEERING they have no match in the ham business. 100 stars out of 5! If you outside of the USA  DXENGINEERING is the company to do business with, they have no match. in all areas of  servicing their customers. We have not even mentioned their excellent product range!

We all know its  a "receiver test data" league table.   The point is that its gets annoying when  people will go around claiming that they have the best radio  because they only consider receiver  specifications. There is two sides to the equation, receiver performance and transmitter performance. If I bought something thats claimed to be the best  I would want the item to be perform well in  all areas of its operation not just in one area.  If I went out and bought a  Rohde-Schwarz EK2000 transceiver today I know I would be buying something that has both a perfect transmitter and receiver. For that  matter it would be perfect and meet all its claimed design specifications. What we typically  get when we buy a very expensive amateur transceiver  is a radio that generally  is far from perfect and probably has several failings.  If it was beer  money I would not complain, but these days radios are getting very expensive and the price creep is getting very close to full commercial  mil spec radios. For the money I think I deserve to get  something better and that performs better than a 100 dollar CB radio. Unfortunately thats what you typical get in ham transceiver, a transmitter whose IMD specifications is just as bad as the average CB radio. Its pure folly to turn a blind eye to the failings of amateur transmitters because they are crap.

You dont have to tell Rob Sherwood what to do, he knows  that transmitter performance should be considered. Rob does not have the time and resources to do all this testing. The people you should be dressing down is the ARRL who collects my and your money  and are the one who turn a blind eye to radios with bad IMD performance.  The ARRL also has the resources to do the job, but they  dont seem to want to get into the business of being critical of their advertisers.

One aspect of SDR radios not covered in this presentation  is HF direction finding.  SDR receivers with phased locked and disabled AGC's make excellent DF receivers.
Very soon it will be possible to locate jammers very quickly, right down to their house number! Single Site Locate direction finding is within in read of hams today. Some progress has been made
towards the first steps in this area.

http://k5so.com/HPSDR_downloads.html
mercury triple direction finding  program.

With the large number of hams, building a wide area international high accuracy DF system is entirely possible. With the internet and GPS clocks readily available super resolution DF systems does
not only have to be in government  offices. DF algorithms like  MUSIC and ESPRIT are in the public domain and can be easily implemented in mathlab.

Another area that would  also open up is the possibility of measuring the propagation incoming angles of arrival and automatically selecting the best antenna for the path.

Other areas like beam steering for avoiding QRM will be another possibility. Down conversion radios can deliver great performance but in todays world they are really dinosaurs on the path towards rapid extinction.

SDR receivers make great spectrum analyzers for monitoring transmitters, a application you rarely seen mentioned. These days there is no reason why you should be transmitting a crap signal when softrocks are so cheap.

Maybe they are re-designing the 13.8 volt CB PA and are busy working on an adaptive pre-distortion high voltage FET PA. I heard that there is shortage of CB bipolar transistors from Japan because of nuclear accident, maybe thats the reason for the Flex 6000 delay.

The reality is that the Hilberling is really the only radio in the top 5 list that deserves to be there. The reason I say this is its excellent transmitter IMD performance. The  Hilberling has very well engineered PA that  really outperforms all the radios in both 2 tone IMD and and dynamic voice  IMD performance. The is a great contribution to  the ham radio market. Hilderbling can hold its head high for producing a radio with both an excellent receiver and  superbly clean transmitter.

  If Sherwood reorganized his list by transmitter IMD performance  the only radio that would be on a transmitter league performance would be the ADAT and Hilberling. In terms  of spec-manship Hilberlberling and ADAT get it. When will the other ham  manufacturers produce transceivers with impressive transmitters? I guess they like fooling hams with impressive receiver numbers and dont want to tell them that they dont have a hope in hell of using all the impressive number radios on the hams bands because we basically jamming each other with crud  from poor transmitters.

The smat guys are really the ones who are buying cheap radios like the IC718 and IC706 because in reality on busy bands thats all the receiver performance you can use on SSB. I suppose its like owning a Ferrari in Tokyo or Bangkok, you can brag to all your friends how fast you can go but you will never go faster than10mph if you lucky!  When will hams wake up, its amusing that all the radios with the best receiver numbers besides the Hilberling have basically got crap poor IMD transmitters. Look at the K3 poor TX IMD and poor keying sideband suppression but its the best in the world in everyone's eyes because its on top of a list.

A more interesting chart would be to show the dynamic range figures at 5, 10, 15 and 20 khz spacings. Then below that show the average TX IMD performance. You can will soon get the picture how meaningless high receiver numbers look when signals approach the blocking limits.

Dynamic range  figure KHZ             5      10    15    20  spacing
                                                100     105  110  120  Db

Typical transmitter ham IMD         25    30    40   50     Db
Ideal transmitter would be            50     60    70   80     Db

When you draw a chart like above you quickly see how man DB's in receiver performance is wasted simply because the transmitter performance is so poor. Its a no brainer,  but hams  are just getting sold
all hype about excellent receiver performance numbers. The jokes on us! Hilberling deserves a medal for designing a transmitter with excellent commercial IMD performance.

The next joke on Sherwoods list will be the TS990S, same deal, all receiver performance, costs a lot and will probably  have a crap transmitter with ALC induced splatter.

 You can always tell that a product has been  rushed onto the market  and will have short lifespan when its a super expensive transceiver and it has a lousy 12 volt 100 watt  CB design PA in it!
If I wanted to call my product state of the art and the greatest thing since sliced bread, I would have at least put in a 200 watt modern FET PA into the  like most of the current super expensive radios like the IC7800.

Feature like external GPS reference lock would also not be a option.  This simple bit of electronics a school kid could design why is it even a option? Things like adapter feed forward PA and  direction finding could be a option,
but not frequency reference locking.

All I can say is, all that MIPS and they cant do adaptive pre-distortion  with a decent PA?

The whole Flex concept has been  rushed concept that has many holes in it that does not  hold water for a supposedly ground breaking product. Even on paper the ADAT transceiver has
more credibility since they have delivered on every design feature and stated objective.

Thinks like beam steering and  direction finding wont see the light of day because its all hyperbola concepts. Whoever makes the promises wont have the skills to deliver this technology and make it really work.
The Flexradio 6700 just looks like a brain storming session product that probably has not been though out well enough. When you examine SDR product like those delivered for professional markets and for things
like beam steering and HFDF, you soon see that all of Flex Radios hyperbola lacks substance.

http://www.roke.co.uk/locate/

Look carefully through the specifications  and performance requirements of these professional receivers and you will soon understand  the hyperbola.

Have a look the KX3 could be this

http://www.reuter-elektronik.de/index.html

Simple 19 inch rack box with  KX3, power supply and 200 watt FET PA. A simple touch screen front panel running  any embdedded ARM processor, the result a hot knobbed SDR radio.

The possibilities are endless, some people just need to stop drinking Koolaid or maybe they should add some LSD to the Koolaid to get some color and imagination.

A radio that is dependent on a PC is a archaic tool that wont have place in the future. Witness the success of tablets. If everyone thinks they always going to be  able to buy a desktop PC in the future they  in for a rude awakening.
Typing your product to a PC based platform is a recipe for planned obsolescence. A Android tablet that could plug into the KX3 would be  a fantastic future option that would radically transform peoples thinking about knobbed radios.