I wish I could say I had such prescience! Alas! I don't.
Kim N5OP
"People that make music together cannot be enemies, at least as long as the
music lasts." -- Paul Hindemith
On Jun 21, 2013, at 1:55, "Rick - DJ0IP / NJ0IP" <Rick@DJ0IP.de> wrote:
> Kim, you may have just come up with a great concept for planning a contest
> radio station.
> "Always live south of your competitors".
> It's the same over here too, we almost never point the beam south.
> You work an occasional multi to the south, but then you point the beam back
> to the NE or NW where the action is.
>
> 73
> Rick, DJ0IP
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Kim Elmore
> Sent: Friday, June 21, 2013 5:19 AM
> To: Rick - DJ0IP / NJ0IP
> Cc: 'Discussion of Ten-Tec Equipment'
> Subject: Re: [TenTec] RF Speech Processor "TX IMD"
>
> Sorry for the delayed response.
>
> Yep, I misunderstood: no amount of filtering on a rx will fix a poor tx.
> Nothing can be done about transmitted phase noise or poor IMD of a tx once
> it leaves the tx.
>
> I was reminiscing about K0RF back in the late 80's/early 90's when he was
> running a TS-930S. That was about as good as anything got back then.
> We certainly have much better, now. He has truly fantastic antenna array and
> full QRO Alpha amps (or did back then) and when he was pointed at me, about
> 10 mi south, all I could do was switch bands. Fortunately, he wasn't
> compelled to do that very often in a contest simply because a lot of mults
> are in other directions.
>
> Kim N5OP
>
>
> On 6/18/2013 3:12 PM, Rick - DJ0IP / NJ0IP wrote:
>> Reply No. 2 on this, Kim...
>>
>> I thought K0RF was now running an FT-5000 in class A mode, driving a
>> very good linear.
>> As such, I assume you are speaking historically.
>> You shouldn't have any problems with him anymore.
>>
>> 73
>> Rick, DJ0IP
>>
>> -----Original Message-----
>> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of
>> Kimberly Elmore
>> Sent: Tuesday, June 18, 2013 6:27 PM
>> To: Discussion of Ten-Tec Equipment
>> Subject: Re: [TenTec] RF Speech Processor "TX IMD"
>>
>> Yes, indeed: the introduction the PLL lead to wonderful flexibility in
>> frequency coverage and generation along with mounds of phase noise.
>> The phase noise has been largely corralled, but not IMD. I wonder:
>> what IMD level is good enough? Something around -40 dB seems considered
> insufficient.
>> Would -50 dB do it? -60 dB? What things affect the linearity and
>> transfer function of a PA? Can IMD be "designed out" of a PA, or is it
>> fundamentally caused by the transfer function inherent in the active,
>> amplifying device (transistor or tube) itself? I honestly don't know.
>>
>> Oh, and when I heard K0RF's phase noise, I was about 10 mi from him :)
>>
>> I will take issue with one aspect, though: band pass filters on the
>> output of a transmitter can most certainly attenuate phase noise, or
>> any other emitted RF, that falls outside the filter's pass band. Phase
>> noise is Gaussian (white) in nature and we can turn white noise into
>> anything we want with proper filtering. There's nothing special about
>> phase noise or nth-order IMD products in this regard: band pass
>> filters pass only what's in the pass band (the ultimately tautology!).
>> The pass band may be, say, the entire 20 m band plus a bit for safety,
>> but a good filter will stop anything outside of the pass band. So, a
>> transmitter with a good band pass filter on it won;t much affect any other
> band but 20 m.
>>
>> I'll take my '930S out again this year and double check its noise
>> generation as I know darn good and well that it makes some. I'll even
>> try it on 'phone to see how much trash it makes because I really don't
>> have any idea right now. No, I don't don't own the proper equipment,
>> such as a spectrum analyzer, to allow me to measure it. I suppose that
>> makes me an inadequate ham in some eyes (hangs head in shame).
>>
>> Kim N5OP
>>
>>
>> ________________________________
>> From: Rick - DJ0IP / NJ0IP <Rick@DJ0IP.de>
>> To: 'Discussion of Ten-Tec Equipment' <tentec@contesting.com>
>> Sent: Tuesday, June 18, 2013 10:03 AM
>> Subject: Re: [TenTec] RF Speech Processor "TX IMD"
>>
>>
>> Guys, this is EXACTLY what I have been talking about.
>>
>> BROADBAND PHASE NOISE - not just the 3rd order IMD.
>> This noise is not just wide, it's across the entire spectrum.
>>
>> Now hang a 1.5KW linear amp on one of those!
>> You don't just bother others on your block, you bother those within a
>> couple of miles.
>>
>> But of course some of the rigs are also pathetic on the higher order IMD.
>> NONE are as good as a 1960s Collins 30S-3.
>>
>> (OK, sure the FT-5000 is if you run it at 75w in class A, but as soon
>> as you turn on the speech processor, it's hosed too!)
>>
>> Nearly 50 years, not only have we seen no progress, the IMD has gotten
>> worse.
>>
>> 73
>> Rick, DJ0IP
>>
>>
>> -----Original Message-----
>> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Duane
>> Calvin
>> Sent: Tuesday, June 18, 2013 4:49 PM
>> To: 'Discussion of Ten-Tec Equipment'
>> Subject: Re: [TenTec] RF Speech Processor "TX IMD"
>>
>> Same with the TS-430. I have a neighbor less than 500' away running
>> CW all the time. When he had his TS-430 he covered a major portion of
>> the band he was on with transmitted phase noise. It was a pure
>> delight when he up graded to a TS-570 a few years ago and then I
>> couldn't hear him until I was within 5-10 KHz of him or so.
>>
>> 73, Duane
>>
>> Duane Calvin, AC5AA
>> Austin, Texas
>> www.ac5aa.com
>>
>>
>>
>>
>> -----Original Message-----
>> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Barry
>> N1EU
>> Sent: Tuesday, June 18, 2013 9:41 AM
>> To: Discussion of Ten-Tec Equipment
>> Subject: Re: [TenTec] RF Speech Processor "TX IMD"
>>
>> On Tue, Jun 18, 2013 at 1:16 AM, Kim Elmore
> <cw_de_n5op@sbcglobal.net>wrote:
>>
>>> All that said, I never tried phone with it at FD but I'll give it a
>>> shot this year as a quick test to see if the IMD wipes out everyone else.
>> We use a TS930S on ssb every year at Field Day and it just wipes out
>> the rig that's down in the cw portion of the same band due to phase noise.
>>
>> Barry N1EU
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