[TenTec] Tx IMD and Purity

Bob McGraw - K4TAX RMcGraw at Blomand.net
Mon Jul 1 13:50:45 EDT 2013 

I don't think designers are cutting corners on PA designs.  There are limits 
as to what can be obtained with a 12V radio design.  Thus I do think, even 
for a 100 watt radio, we need to get away from 12V radios.  Now that brings 
up another issue and that is the "internal power supply" would be a must.  I 
certainly do not have a problem with this and would think a 50 volt supply 
would improve IMD values for a 100 watt radio by some 20 to 30 dB.  In other 
words, IMD in the order of -55 dBm.   It makes for one box, fewer cables and 
fewer ground loop issues and less space on the desk required.  A good 
switcher is self regulating, auto line voltage sensing, very efficient on 
energy and electrically clean and is very light weight when compared to an 
external linear supply or a storage battery.

The IMD crud on the bands today gives us false needs for better receivers 
when indeed the true solution is radios that produce less noise and 
distortion products.  On another point, I've recently measured two current 
production radios and observed that they are broadband noise generators. 
With the mike gain turned down, no mike connected, key the radio and watch 
the noise from 0.5 MHz to 30 MHz rise.  In one I measured the level at -55 
dBm which is equal to a S-9 +8 dB signal over the 0.5 MHz to 30 MHz range. 
It makes a good broadband noise generator.  Connect it to a multiband 
antenna and it radiates on all bands equally  well.  There is simply no 
technical reason this should take place.

73
Bob, K4TAX




----- Original Message ----- 
From: "Kimberly Elmore" <cw_de_n5op at sbcglobal.net>
To: "Discussion of Ten-Tec Equipment" <tentec at contesting.com>
Sent: Monday, July 01, 2013 12:14 PM
Subject: [TenTec] Tx IMD and Purity


> Rick, you make an excellent point! Are you speaking of only IMD 
> performance? If so, how good is good enough? Speaking only of 3rd order 
> (O3) IMD, my old TS-930S has O3 IMD of -35 dB while my Orion II has a 
> worse value of -28 dB. The best available may be the FT-2000D running 
> class A, with O3 IMD below -41 dB (the QST article noted that this was as 
> low as the ARRL could measure). At -30 dB, the transmitted power of the O3 
> IMD with 100 W PEP is 0.1 W PEP. If I add a (perfect) amp with ~12 dB of 
> gain, I'll see 1.5 W PEP of transmitted O3 IMD. If we were to set a target 
> for transmit IMD numbers, what do you think it should be? Is there 
> something the manufacturers can do to meet these goals aside from running 
> everything class A? Should everything run off of a 28 V or 56 V supply 
> or...?
>
> I'm sincere in my question because I don't know enough about PA design to 
> know if the manufacturers are cutting corners that make otherwise 
> efficient transmitters dirtier than they need to be.
>
> 73,
>
> Kim N5OP
>
>
>
>
> ________________________________
> From: Rick - DJ0IP / NJ0IP <Rick at DJ0IP.de>
> To: 'Discussion of Ten-Tec Equipment' <tentec at contesting.com>
> Sent: Monday, July 1, 2013 10:50 AM
> Subject: Re: [TenTec] Orion II has ended production
>
>
> But it affects all of us.
> So it's our misery too.
>
> BTW, though Ten-Tec doesn't produce any really bad ones, their signals are 
> far from being good.
> The TX IMD of the Kenwood TS-590 is not particularly good . . . yet it is 
> better than my Eagle.
> :-(
>
> (so I work CW - hi).
>
> 73
> Rick, DJ0IP
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces at contesting.com] On Behalf Of k6jek
> Sent: Monday, July 01, 2013 5:46 PM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] Orion II has ended production
>
> Perhaps the lack of emphasis on transmit cleanliness is that it's somebody 
> else's misery
>
> On Jul 1, 2013, at 8:34 AM, Rick - DJ0IP / NJ0IP wrote:
>
>> Well if we are pointing out Rob Sherwood points, let's not forget that 
>> ONE BIG POINT he makes is, there is no further need to continue work on 
>> the receiver technology now, until we fix the dirty transmitters on the 
>> band.
>>
>> Why is it nobody ever wants to talk about this? Everyone talks receiver, 
>> receivers, receivers....
>>
>> A good receiver is one that does not crunch in the presence of a strong 
>> station on a neighboring channel.
>> But if that station is a strong signal using many of today's rigs, 
>> driving an amp, he's not just on the neighboring channel.
>> He's splattering across your frequency and there are no receiver features 
>> for removing that.
>>
>> 73
>> Rick, DJ0IP
>>
>> -----Original Message-----
>> From: TenTec [mailto:tentec-bounces at contesting.com] On Behalf Of Ted
>> Bryant
>> Sent: Monday, July 01, 2013 5:12 PM
>> To: 'Discussion of Ten-Tec Equipment'
>> Subject: Re: [TenTec] Orion II has ended production
>>
>> Amen, Bob.
>>
>> In addition to the audio issues in current radios, Sherwood has 
>> demonstrated how AGC performance can seriously affect the ability to copy 
>> stations in the presence of noise, especially pulse-type noise. AGC 
>> performance is yet another factor rarely mentioned and certainly not 
>> reflected in "the charts".
>>
>> A couple more interesting (and often overlooked) points that Sherwood 
>> makes:
>> 1 - receiver requirements are more demanding for cw contesting/DXing
>> than ssb
>> 2 - a receiver with about 80db dynamic range is entirely adequate for
>> most contesting/DXing situations
>>
>> 73, Ted W4NZ
>>
>>
>> -----Original Message-----
>> From: TenTec [mailto:tentec-bounces at contesting.com] On Behalf Of Bob
>> McGraw - K4TAX
>> Sent: Monday, July 01, 2013 10:08 AM
>> To: Discussion of Ten-Tec Equipment
>> Subject: Re: [TenTec] Orion II has ended production
>>
>> Rick brings forward a point which is one objection that I find with the 
>> use of the Sherwood Engineering report, i.e. "the charts".
>>
>> ***** Let me make it clear, Rob's test data and tests are very
>> accurate, very useful and very valid. *****
>>
>> The fallacy is hams seem to believe solely in the ranking position on the 
>> report and they fail to acknowledge that radios are ranked according to 
>> ONE
>> FACTOR only. They seem to neglect other factors which I find to equally
>> or in some cases more important.
>>
>> To Ricks point, if a radio for example, is rated in the top 10 in the 
>> "chart" and it has poor audio as some do, then does this make it a great 
>> radio? My take, if it has a great receiver performance but has bad audio,
>> it is a lousy radio.   I agree totally with Rob's assessment presented at
>> Dayton in that a radio must be easy to use and enjoyable to use. Failing 
>> these two points, it is not a "good" radio regardless of the numbers or 
>> the ranking position on the "charts".
>>
>> I've found that the Sherwood Engineering report can be downloaded to an 
>> EXCEL file where upon one can sort or parse the values based on 1 or 2 or 
>> 3 different values or parameters. Still even with this, it does nothing 
>> to reveal the audio performance, TX performance or "use-ability" of a 
>> brand or model. To evaluate a product without having one side by side 
>> with another, the reports including the Sherwood Engineering report, the 
>> product review by ARRL Lab and by RSGB serve as outstanding sources. I 
>> suggest taking these reports and building ones own EXCEL spreadsheet to 
>> attain model by model paper comparison. Yet this still does nothing for 
>> the "usability" factor.
>>
>> In looking at the current "chart" publication (22 June 2013) , I find
>> that 7 of the top 10 lines are USA made products. I think that
>> certainly speaks well of US designed and manufactured products. This
>> of course is based on ONE FACTOR only. :-)
>>
>>
>> 73
>> Bob, K4TAX
>>
>>
>> ----- Original Message -----
>> From: "Rick - DJ0IP / NJ0IP" <Rick at DJ0IP.de>
>> To: "'Discussion of Ten-Tec Equipment'" <tentec at contesting.com>
>> Sent: Monday, July 01, 2013 3:08 AM
>> Subject: Re: [TenTec] Orion II has ended production
>>
>>
>>> Joe, don't just "take a look", use your ears and "listen" to the K3.
>>>
>>> I did, and I compared it to an Eagle, side by side for about a month.
>>> I sold the K3. Crappy audio.
>>> And NO, the firmware update did not fix it. It just improved it.
>>> It's still bad audio.
>>>
>>> 73
>>> Rick, DJ0IP
>>>
>>>
>>> -----Original Message-----
>>> From: TenTec [mailto:tentec-bounces at contesting.com] On Behalf Of Joe
>>> W2KJ
>>> Sent: Sunday, June 30, 2013 3:23 AM
>>> To: Discussion of Ten-Tec Equipment
>>> Subject: Re: [TenTec] Orion II has ended production
>>>
>>> Take a look at the Elecraft K3...it's receiver(s) are at the top of
>>> the charts.
>>>
>>> I have a K3 and really enjoy using it...best receiver I have used in
>>> 51 years of hamming...oh, and the QSK ain't bad either (grin).
>>>
>>> I sold my Orion a while back after being disappointed that Ten Tec
>>> didn't really follow up on firmware updates for many months after
>>> bugs were discovered and reported.
>>>
>>> With John Henry back in the company hopefully that won't be the case
>>> anymore.
>>>
>>> Interested in what Ten Tec will follow the Orion family with.
>>>
>>> 73, Joe W2KJ
>>>
>>>
>>>> That's my biggest concern that firmware development will cease...
>>>>
>>>>
>>>>
>>>> I hope until Ten-Tec has a replacement for it’s flagship it will
>>>> continue to develop firmware releases for the Orion. I also hope
>>>> the sub receiver upgrade will continue to be available for a
>>>> while...been saving my pennies for that addition to my Orion II.
>>>>
>>>>
>>>>
>>>> It’s ashamed really...there is not another product in the market
>>>> positioned where the Orion II sits. One has to spend a considerable
>>>> amount of money above the cost of the Orion II to purchase a desktop
>>>> transceiver (non-PC based) with the feature set the Orion II possesses.
>>>> With Icom it’s the 7800 at $13000.00 or with Yaesu it’s the 5000 at
>>>> I don’t know how much. (they dropped the 2000) Now Kenwood has the
>>>> 990 but it’s too new to be fully sorted out and it’s a few K$ more than 
>>>> the OII....
>>>>
>>>>
>>>>
>>>> There are many radios out there...but few with dual receivers and
>>>> dual tuning knobs which has become a must have in a DX radio for
>>>> me.... Don’t do point and click radio’s either....
>>>>
>>>>
>>>>
>>>> Just a personal thing...
>>>>
>>>>
>>>>
>>>> Guess that makes the Elecraft K3 the winner....at lease one can
>>>> start basic and grow it to the level of the radios mentioned above....
>>>>
>>>>
>>>>
>>>>
>>>> Cecil Acuff
>>>> Gulfport MS
>>>> K5DL
>>>>
>>>>
>>>> From: Kim Elmore
>>>> Sent: ‎June‎ ‎29‎, ‎2013 ‎4‎:‎06‎ ‎PM
>>>> To: Bob Gibson; Discussion of Ten-Tec Equipment
>>>> CC: Discussion of Ten-Tec Equipment
>>>> Subject: Re: [TenTec] Orion II has ended production
>>>>
>>>>
>>>> All radios cease production at some point, so this was inevitable.
>>>> It doesn't make our radios worthless or perform any worse.
>>>>
>>>> What's not clear is how much additional firmware development there
>>>> will be in the future. I hope TenTec doesn't cease all development,
>>>> but their resources are limited and we can't expect firmware
>>>> development to continue indefinitely. Someday, firmware support will 
>>>> have to end.
>>>>
>>>> Kim N5OP
>>>>
>>>> "People that make music together cannot be enemies, at least as long
>>>> as the music lasts." -- Paul Hindemith
>>>>
>>>> On Jun 29, 2013, at 15:54, Bob Gibson <w5rg at yahoo.com> wrote:
>>>>
>>>>> I wish I had known this two weeks ago when I bought a new one!!
>>>>>
>>>>> Bob Gibson W5RG
>>>>>
>>>>>
>>>>> ________________________________
>>>>> From: PC Anderson <xtraham58 at hotmail.com>
>>>>> To: Discussion of Ten-Tec Equipment <tentec at contesting.com>
>>>>> Sent: Saturday, June 29, 2013 2:30 PM
>>>>> Subject: Re: [TenTec] Orion II has ended production
>>>>>
>>>>>
>>>>> Looks like my comments were blocked.
>>>>> Andy W3LI
>>>>>
>>>>>>
>>>>>>
>>>>>> Thanks for the heads up Ron.
>>>>>>
>>>>>> Guess I'm shaking my head at why they couldn't "Eaglize" the Orion
>>>>>> RF design and update the controller/display/etc and end up with an
>>>>>> Orion III.
>>>>>> I love the Orion form factor.
>>>>>>
>>>>>> 73,
>>>>>> Barry N1EU
>>>>>>
>>>>>> On Sat, Jun 29, 2013 at 6:14 PM, Ron Castro <ronc at sonic.net> wrote:
>>>>>>
>>>>>>> I just got this in the TenTec newsletter:
>>>>>>>
>>>>>>> "On a rather sad note, about the time you read this message, we
>>>>>>> will have sold out of the last 566 Orion II transceiver.
>>>>>>> Unfortunately, due to the availability of some very critical
>>>>>>> parts plus skyrocketing prices for difficult components, the
>>>>>>> staff at TEN-TEC decided to discontinue this product. This does
>>>>>>> not mean we will not trade or sell used and demo Orion's and Orion 
>>>>>>> II models.
>>>>>>> We will continue service and support this product as we have done
>>>>>>> in the past with all TEN-TEC products. Is a new Orion III on the
>>>>>>> horizon? There are plans for several new TEN-TEC products lined
>>>>>>> up for the future but at this time no concise decision has been
>>>>>>> made for another Orion transceiver."
>>>>>>>
>>>>>>> All good things come to an end...
>>>>>>>
>>>>>>> Ron Castro
>>>>>>>   N6IE
>>>>>>> www.N6IE.com
>>>>>>>
>>>>>>> Member:
>>>>>>> ARRL
>>>>>>>   Redwood Empire DX Assn.
>>>>>>> Northern California Contest Club
>>>>>>> Northern California DX Foundation
>>
>>
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