Bob,
On that current production brand name model you are referring to must be what a
fella was using one night driving a linear on 160 M and QRMing us on 80 meters.
The Op came on our freq later and apologized and said he'd check his equipment
out before getting on 160 again.
Eric
W9WLW
On April 23, 2014 7:55:19 PM EDT, Bob McGraw - K4TAX <RMcGraw@Blomand.net>
wrote:
|I too found that I got great audio or great signal reports with one of
|my
|radios. Those glowing audio reports are "on frequency" reports. I
|looked at the real output of a radio on my desk and saw all the crap
|being
|generated and transmitted some 20 kHz to 30 kHz away. I find it is
|the
|"off frequency" thus adjacent noise and IMD products that create a lot
|of
|unnecessary noise and pollution on the bands. And as users, it is
|difficult
|to find the source in many cases. For normal operation I use a
|spectrum
|analyzer connected to the receiver bandpass filter. With that
|configuration
|one can see much of the noise being generated as a certain signal
|appears
|and disappears thus correlating the noise change.
|
|As and example, look at the numbers. Take a given strong signal that
|is S-9
|+ 20 dB at your receiver. Then presume his IMD products are only 35 dB
|
|down. That then says his IMD products are equivalent to a S-6 signal.
| I
|realize that in many cases our local noise level is S-6 but be assured,
|that
|stations presumable IMD products contribute to the local noise level as
|
|well.
|
|I own one current production and very popular brand/model radio. When
|this
|radio is in transmit the noise on all HF bands increase 10 dB to 20 dB.
|
|That's right, transmit on 160M and the noise on 10M increases 10 dB.
|Put it
|in a Field Day environment and you'll likely learn some new vocabulary
|words
|from other operators. Put that radio on the same band as another radio
|and
|when it is transmitting the other radio on the same band is totally
|deaf.
|
|Yes, it is time to start a clean up of our spectrum. Unfortunately,
|many of
|the older radios are major contributors and even some of the new
|current
|technology ones aren't much if any better. And then there's the
|operator
|issues, taking a marginally spectrally clean radio and adding 10 dB to
|12 dB
|of gain via a linear amp that may not be tuned correctly thus
|amplifying and
|generating more pollution.
|
|73
|Bob, K4TAX
|
|
|
|
|
|
|
|
|
|
|----- Original Message -----
|From: "Carl Moreschi" <n4py3@earthlink.net>
|To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
|Sent: Wednesday, April 23, 2014 5:08 PM
|Subject: Re: [TenTec] OT: Rob Sherwood's impression of the FLEX 6x00
|
|
|>I get nothing but unsolicited glowing audio reports on my Flex 6500.
|And in
|>the simple test I did comparing transmit noise generated on a band, it
|was
|>at least 30 db less than my Omni VII.
|>
|> Carl Moreschi N4PY
|> 58 Hogwood Rd
|> Louisburg, NC 27549
|> www.n4py.com
|>
|> On 4/23/2014 5:45 PM, Bob McGraw - K4TAX wrote:
|>> Yes, and it looks to me that some of the IM measurements do not meet
|>> current FCC requirements. I wonder who and how the certification
|>> measurements were conducted.
|>>
|>> Of course I'm sure these aren't the only certification values that
|were
|>> pushed through so the product could be sold. It seems that companies
|do
|>> that these days more frequently than not.
|>>
|>> I agree, we do need vast improvements with products on the air
|today. I
|>> could imagine a situation much like pollution testing for vehicles.
|It
|>> is up to the manufacturer to design it to meet specs and up to the
|user
|>> to keep it in that condition. Unless grandfathered in, that would
|>> obsolete a lot of radios unless the user modified them to meet
|specs.
|>> And that in most instances would be next to impossible.
|>>
|>>
|>> 73
|>> Bob, K4TAX
|>>
|>>
|>>
|>>
|>>
|>>
|>> ----- Original Message ----- From: "Rick - DJ0IP / NJ0IP"
|<Rick@DJ0IP.de>
|>> To: <k9yc@arrl.net>; "'Discussion of Ten-Tec Equipment'"
|>> <tentec@contesting.com>
|>> Sent: Wednesday, April 23, 2014 3:30 PM
|>> Subject: Re: [TenTec] OT: Rob Sherwood's impression of the FLEX 6x00
|>>
|>>
|>>> Jim, it is nasty compared to a Collins 32S3 transmitter and to
|radios
|>>> with
|>>> 50v transistors, but compared to most radios shipping today with
|12v
|>>> transistors, it seems to be average.
|>>>
|>>> Which is why I have been saying for a long time that we need to
|start
|>>> SCREAMING at the OEMs to clean up their act!
|>>>
|>>> 73 - Rick, DJ0IP
|>>> (Nr. Frankfurt am Main)
|>>>
|>>>
|>>> -----Original Message-----
|>>> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of
|Jim
|>>> Brown
|>>> Sent: Wednesday, April 23, 2014 10:15 PM
|>>> To: tentec@contesting.com
|>>> Subject: Re: [TenTec] OT: Rob Sherwood's impression of the FLEX
|6x00
|>>>
|>>> On 4/23/2014 7:43 AM, Rick - DJ0IP / NJ0IP wrote:
|>>>> I have just uploaded Rob's report of his experience using the
|newest
|>>>> FLEX Radio to my web site.
|>>>
|>>> VERY nasty IM -- run this thing into an amp and you're going to
|make a
|>>> lot
|>>> of enemies!
|>>>
|>>> 73, Jim K9YC
|>>> _______________________________________________
|>>> TenTec mailing list
|>>> TenTec@contesting.com
|>>> http://lists.contesting.com/mailman/listinfo/tentec
|>>>
|>>> _______________________________________________
|>>> TenTec mailing list
|>>> TenTec@contesting.com
|>>> http://lists.contesting.com/mailman/listinfo/tentec
|>>>
|>>
|>>
|>> _______________________________________________
|>> TenTec mailing list
|>> TenTec@contesting.com
|>> http://lists.contesting.com/mailman/listinfo/tentec
|>>
|> _______________________________________________
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|
|
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Sent from my Android device with K-9 Mail. Please excuse my brevity.
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