For a slightly different answer, take a look at my website www.w3fpr.com
article on Antennas, Transmission Lines, and Tuners.
You can also find that same article preserved at
https://www.qsl.net/w3fpr/ant_article.htm.
73,
Don W3FPR
On 4/9/2019 8:56 PM, Don Sanders wrote:
Since no one has
I agree except that even at 500KW a 2:1 or greater is the norm with open wire
line.
Sent from my iPhone
> On Apr 9, 2019, at 19:10, Fred Jensen wrote:
>
> Well, the reflected power is created by a "virtual transmitter" at the
> feedpoint of the antenna and heads down the coax which has a
Well, the reflected power is created by a "virtual transmitter" at the
feedpoint of the antenna and heads down the coax which has a surge
impedance of Z0 ohms. It meets the SO-239 at the TX and sees an
impedance of Z1, the impedance presented by the PA and output filters.
If Z1=Z0, the power
Since no one has answered your question. I will venture a
supposition that many know but few will speak out.
And some still remember their CB days and the erroneous
advertising saying the power is lost.
Reflected Power flows back down the feed line and is subjected
to the normal feed line loss. It
Thanks to Andy and Jack for replies on my question about the alarm on
the KPA500. I have a couple of ways to go with this now, and am
grateful for the help.
73, Steve KW3A
__
Elecraft mailing list
Home:
"...Let's allow the reflected power to increase all the way to 10
watts! At that point, your SWR would be about 2 to 1. Sounds pretty bad, but
surely if you were stranded in the desert and had to use your KX3 and a wire
to get help, you'd be happy to have a match this good...(etc.)"
From
Why does everyone seem to think all the secret, hollow mountains are in
Nevada? I know of one in Colorado and another in Virginia. Umm ...
maybe that's in West Virginia, not sure now. [:-))
73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County
I chose these scenarios deviously, to
For an interesting discussion..."What happens to the power that's reflected?"
On 4/9/2019 3:42 PM, Al Lorona wrote:
There's always a lot of discussion about measuring SWR, low SWR values, SWR
lights not lighting up, etc. Here's something that might give you a better
'feel' for SWR.
Imagine
Oh My God! A voice of reason! And from here of all places! How absolutely
unexpected!
Thank you sir.
> On Apr 9, 2019, at 12:42 PM, Al Lorona wrote:
>
> There's always a lot of discussion about measuring SWR, low SWR values, SWR
> lights not lighting up, etc. Here's something that might
What is the value of R4? It should be 100k.
73,
Don W3FPR
On 4/9/2019 4:54 PM, TI2/NA7U wrote:
Manual says D13 (banded end) should show between 90-150V, mine measures 178V
... says U4 pin 8 should be between -5 to -25 V, mine measures -30V
Still going through the receiver tests, up to the
Manual says D13 (banded end) should show between 90-150V, mine measures 178V
... says U4 pin 8 should be between -5 to -25 V, mine measures -30V
Still going through the receiver tests, up to the dual-supply tests and all
seems well, so should I be concerned about those readings?
73,
TI2/NA7U
Thank you Al Lorona!
73
Bob, K4TAX
On 4/9/2019 2:42 PM, Al Lorona wrote:
There's always a lot of discussion about measuring SWR, low SWR values, SWR
lights not lighting up, etc. Here's something that might give you a better
'feel' for SWR.
Imagine that you measure your forward power at 100
My friend Al has described some interesting things about SWR measurement here.
But not all power/swr meters behave this way. In fact the Elecraft W2 meter is
in this class. The designer added an ingenious little circuit to the diodes to
bias them into their linear region. What the smeans is
Thank you, Jim N4ST, for expressing something which I had become afraid to
(having been stung by wasps too many times)
73,
Joan KX2CW
Darmok and Jalad at Tanagra, said Piglet.
Shaka, when the walls fell, said Pooh.
> On Apr 8, 2019, at 10:41, Jim - N4ST wrote:
>
> Ken,
>
> The Internet has
Fred:
If you take a manual on a thumb drive, Staples can print it and spiral-bound
it.
Tom W4KX
Sent from my iPad
> On Apr 9, 2019, at 2:44 PM, Fred Jensen wrote:
>
> Yes, the USAF Technical Orders for a system could fill a bookcase if printed,
> and they were printed then. I don't
There's always a lot of discussion about measuring SWR, low SWR values, SWR
lights not lighting up, etc. Here's something that might give you a better
'feel' for SWR.
Imagine that you measure your forward power at 100 W and your reflected power
at only 1 W. You'd probably be very happy about
And some of today's software applications {HRD} have provision for
MCW. One must be careful how the interface between the computer and
radio is constructed so as not to have anything in the audio path which
would contribute to less than a pure sinewave signal. Actually this
is exactly
Yes, the USAF Technical Orders for a system could fill a bookcase if
printed, and they were printed then. I don't remember many of the
volumes but the -1 was "How to fly the airplane" [or operate the radio],
-6 was the Illustrated Parts Breakdown, I think -5 was the parts list.
There was
A technique pioneered by Art Collins many years ago in the KWM2 and S-line.
73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County
On 4/9/2019 3:08 AM, Victor Rosenthal 4X6GP wrote:
Oh no! NOW you tell me that all these years that I have believed that
I have been operating CW, it's really SSB!
It looks like the PS0 power off command still has the note about leaving the
Power On pin on the accessory connector grounded for at least 100ms to
ensure that no internal data is corrupted on the processor.
I'm wondering how hard it would be for the PS0 command to coordinate that
shutdown
Not to worry, Victor. The really important part of generating and
demodulating CW happens in your head.
Eric KE6US
On 4/9/2019 3:08 AM, Victor Rosenthal 4X6GP wrote:
Oh no! NOW you tell me that all these years that I have believed that
I have been operating CW, it's really SSB!
(Disclaimer
Doug,
Yes, thanks, you're right. I have the preamp set up to be active for the
higher bands 12, 10, and 6 m, and in the bypass position otherwise. I use
this to connect an old shortwave receiver (not an SDR) to my main antenna,
so I guess it doesn't hurt for it with the extra gain. But I'll try
David,
Elecraft has the KXPD2, and at last check also has the KXB3080 kit.
So the option that is not available is the KXPD1.
73,
Don W3FPR
On 4/9/2019 5:15 AM, David Cripps wrote:
Hi
Although I've been a ham for nearly 30 years, I've been out the hobby
for the last 25 of them and am now
Sverre,
That answer depends ---
If you want to connect the SDR directly to the antenna, put the TEE
between the ANT OUT and the preamp.
OTOH, if you want to have the preamp in-line for the SDR input, put the
TEE between the preamp output and the ANT IN connector.
If you chose to use the
Thanks, Joe.
Works nicely and saved me the cost of something like the MFJ-1708B-SDR SDR
RF sensing T/R switch!
-
Sverre, LA3ZA
K2 #2198, K3 #3391,
LA3ZA Blog: http://la3za.blogspot.com,
LA3ZA Unofficial Guide to K2 modifications:
"I've pushed my KPA1500 hard in two SSB contests already this year."
I seldom connect a microphone so forgive my ignorance. How is is possible to
push an amplifier hard in SSB (phone) without exceeding legal limit peak output
by a huge margin?
I'd understand "pushing hard" in RTTY or other
After the PR6/PR10 to gain the benefit of the PR6/PR10 for
the SDR as well as the K3/KRX3 receiver(s).
73,
... Joe, W4TV
On 2019-04-09 6:48 AM, Sverre Holm (LA3ZA) wrote:
But what if there is a PR6-10 preamp in this path. Where should the
splitter/TEE-adapter be in that case?
In
I agree with your comments on the amplifier's manual Peter. Getting tech
data right is a challenge. I spent my last six years in the USAF at a
Major Command HQ where I would visit our primary depot twice a year to
discuss product improvement. Tech data was a key part of those meetings.
Even
But what if there is a PR6-10 preamp in this path. Where should the
splitter/TEE-adapter be in that case?
>In brief, it takes a TEE adapter and 2 short pieces of coax. Put the
>adapter between the 2 pieces of coax, and then connect one coax to ANT
>OUT and the other to ANT IN.
-
Oh no! NOW you tell me that all these years that I have believed that I
have been operating CW, it's really SSB!
(Disclaimer to avoid the otherwise inevitable explanations that a pure
audio tone transmitted via SSB is identical with CW: I know that).
73,
Victor, 4X6GP
Rehovot, Israel
Hi
Although I've been a ham for nearly 30 years, I've been out the hobby
for the last 25 of them and am now learning Morse again to get into QRP.
I have recently bought a KX1 and KX2 and would like to get the paddles
for them, so if anybody has a KXPD2 or KXPD1 for sale please let me know
On 4/8/2019 10:52 PM, Peter Hall wrote:
Having spent time, over many years, piecemeal updating Jeppersen and CASA (the
national aviation regulatory authority) pilot documents, I regard it as wasted
time I'll never get back. I hope that Elecraft does not go down this path but
agree
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