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1   HamSphere Ragchewer's Lounge / FS: ICOM PW1 and ELECRAFT K3/P3on April 29, 2023, 16:06:34 UTC

Started by KC5EDU - Last post by KC5EDU

Its ICOM IC-PW1 Solid State 1000W Linear Amplifier/Tuner 160m-6m available.
The unit works flawlessly and when interfaced to an ICOM HF transceiver with the included inter-connect control cable will support automatic band switching and memory tuning.  This is the later version.
The remote panel also as lights dual meters that monitors SWR, ALC, Temp Po, Vo, Io that can be placed adjacent to the transmitter for easy viewing while operating. 
I am including the Palstar DL2K 2kW dummy load and 10 ft inter-connect control cable .
Priced at $1,630.00

Elecraft K3, P3 And Power Supply Combo.
The Set Is In Excellent Cosmetic And Functional Conditions With No Dings, Dents Or Scratches And Has Been Very Well Cared For.
K3 Has Dual Receiver (Main & Sub) And Both Has Same Options (Filters & Boards).
P3 Has SVGA And TX Monitor Options.
Both K3 And P3 Has Latest Firmware Updates Installed.
Accessories:
13.8v 30 Amp Matching Power Supply With AC Power Cable And DC Power Poles Cable. DC Power Cable, RS-232 Cable And BNC To BNC Cable For P3 Panadapter. Elecraft MH2 Hand Microphone. USB To RS-232 Serial Cable For PC To K3 Or P3. User Manuals For Both K3-F And P3-F. Original Factory Shipping Boxes With Inserts.
Prices at $1,410.00

KC5EDU
ROBERTO SEDA
Oklahoma
Whatsapp: +1 (840) 466‑7441
 kc5edu.berto@gmail.com

Started by KI5NPB - Last post by KI5NPB

I am new HAM but have a lifelong scientific approach to empirical data, primarily Computers and Aviation. I make every piece of information I get prove itself out. I read many sites and blogs that have answers to SWR, CMC, Baluns and Antenna Feeds all over the spectrum. Yuck! ALLWAYS and NEVER. My reading (and rereading) of VU2NSBs articles and writings are the clearest I have seen yet. He is still developing this website and still has much unpublished articles. Set SWR and CMC aside for the time being I am trying to work antenna backwards to the transmitter. Currently I see Baluns 1:1 to 1:9, which is correct. 1:1 by DX provides best broadband performance . . . OK what about Antenna Feed Impedance? My current Balun is 5:1 (End Fed wire), mfg. states the 5:1 is best compromise for their broadband antenna. VU2NSB suggest 9:1. After Feed Point issue is settled then I will resolve downstream (Ant. to Transmitter) variables. The ARRL series has a lot of information and math for all of this but still no prospective.

73' David Little KI5NPB

Started by AL7EN - Last post by AL7EN

While doing some research in confirming the degree of realism in the Hamsphere HS4 simulator I stumbled upon the default power level and antenna used in the DR2W Propagation Map which many HS4 users use on a daily basis.  The DR2W Team Website states that the power level of the modeled transmission site is 100 watts and that the default antenna (actually the only available antenna) is a 3/2 WL Monopole (that's 1.5 wavelengths!).  This information hit me like a flopping salmon in the bottom of the boat.  Why would anyone pick such an antenna for this modeling purpose.  Is there some fabulous gain for this antenna?  Does it have a great Take-Off Angle?? 

I began to look at the maps very closely and started estimating the size of the skip zones and the size of the signal arrival zones for the 30, 20, 17 meter bands in North America. The transmission site appears to be in the geographical center of the US so I found out the distance from Lebanon, Kansas to San Diego, CA (frequently the inner edge of the signal arrival zone and that turned out to be 1,085 statute miles.  I averaged the width of several arrival zones for the first skip and they averaged about 800 SM so the center of the first arrival zone of the distance of the first skip would be 1,485 SM.  Going to page 17 of the 1974 edition of the ARRL Antenna Book I find that Figure 1-10 yields a result of 23 degrees Take-Off Angle if F2 is at 261 miles (the upper limit) for a single-hop distance of 1500 miles.  So there does not appear to be anything special in the way of radiation elevation angle with this antenna .And then there is the height of this antenna.

For 80 meters, a 1/4 WL monopole is 20 meters high (about 66 feet).  A 1.5 WL monopole is 120 meters high (or about 394 feet approx.).  There is no advantage with the 3/2 WL antenna over the 1/4 WL antenna in terms of difficulty of construction or maintenance.  Perhaps the advantage is on receive because of a larger aperture?  But the only consideration in the production of the maps is a transmitted signal not a received signal.

Well, I thought there must be some advantage in the gain figure.  I looked up the "HamCAP and Type 13 & 14 Antennas" article by Alex Shovkoplyas, VE3NEA and  there in the listing of the parameters for the 3/2 WL Monopole there is 0.0 gain over a dipole listed.  Alex is one of the authors of the "HamCAP User's Guide". (I have an email into him asking the above questions about this antenna.)

Elsewhere in Alex's article there are parameter inputs for this antenna with a listing of 0.00 db gain and listed as Max Gain dbi which I take to mean "against Isotropic".  Even worse.

OK, I told myself, I'm going to get to the bottom of this.  I emailed Winfried Kriegl, one of the DR2W Team members (DK9IP) and he told me that he did not know why that antenna was the default antenna for their model but I got the impression it was because this was a legacy antenna from the original VOACAP software that their model is based upon.  The DR2W mapping application is more of a shell with the added adjustment of an emphasis placed on Sun Spot Number.

The final result?  I only know this is the last antenna anyone would choose to pay for and erect and I still don't have the take-off number confirmed.  Neither do I have an explanation for the original selection of this antenna for VOACAP purposes (you can still select this antenna...go to VOACAP Online for Hams and check out the vertical antennas!)

I would really appreciate any answers that other forum users might provide!

73 de AL7EN Russ

4   General Discussion / Re: India DX Net - Apr 9on April 11, 2021, 14:03:23 UTC

Started by sp5gng - Last post by G4ELD

Hello Chris it's Gary. I have had a spot of bad luck here and have been operating /A on Hamsphere occasionally in hospital. I may be away from home for a few more weeks but shall keep IDX updated. Background noise is too high most of the time . I think Friday net was cancelled but shall listen again on Monday 73 DE G4ELD

5   General Discussion / India DX Net - Apr 9on April 09, 2021, 12:51:59 UTC

Started by sp5gng - Last post by sp5gng

Nobody's here, hope everything is well, see you on Monday
Chris SP5GNG

Started by Basu (VU2NSB) - Last post by G4ELD

Well after tuning my ears around 80 percent copy. Rusty as I know DE G4ELD. Damned good straight key QSK operation

Started by Basu (VU2NSB) - Last post by KS1K

TKS OM GUD EXERCISE.  73 DE KS1K TU EE

Started by Basu (VU2NSB) - Last post by Basu (VU2NSB)

Are you a skilled CW operator who can comfortably decode Morse code radiotelegraphy transmissions on HF radio bands? Go on, test your skills to find out if you need more practice.

HF radiotelegraphy environment can often be far from ideal. HF radio DX circuits are subjected to a variety of propagation phenomena that might lead to some or all of the following to make life difficult... Are you geared up to negotiate these conditions? Of course, there are many other effects beyond what I have listed below...

  • Deep fading (QSB) - It may either be slow or fast in nature that could at times sink the RX signal below the noise floor.
  • Background Static Noise (QRN) - At different time, band, and operator's QTH, the magnitude would vary. Lightning and thunder would further add to the noise and crackle on the channel.
  • Man-made Noise (QRM) - Not only could the channel be affected by local electrical noise sources but adjacent channel or co-channel interference from other transmissions could produce adverse effects to compound difficulties.
  • Multi-path Propagation phenomena - Signal arriving at the receiver could be via multiple ionospheric skip paths that produce amplitude as well as phase distortion on the received signal
  • Selective fading and non-uniform Group Delay - This could drastically alter the tonal quality and the pitch of the signal at the receiver. The effect could be time-dependent and result in pitch alteration and flutter.
  • Polar Cap Distortion - Many of the intercontinental DX paths have to pass through or adjacent to the polar region. At times when we experience CME and similar solar activities, there is a tendency for increase in Aurora Borealis and Aurora Australis. These result in producing a very hollow sound at the CW radiotelegraphy receiver.

The question is, are you ready to comfortably handle these situations and continue to copy a CW radio transmission with ease? ... Forget the CW decoder software. They will do no good. You have got to be skilled to copy by the ear.

Test your skills below by trying to copy the following recorded transmission.

It is nearly a 35 minutes plain English passage comprising of alphabets, numerals and a few basic punctuation marks. I have not included pro-signs for the sake of simplicity...

The transmission speed is approximately 25 WPM... Now don't say that it is too fast...  :) If you can't copy at this speed then it means that there is a fundamental flaw in the way you were originally taught how to copy Morse code. You need to address this flaw. I will help you do it with a comprehensive set of CW lessons on this website.

The recorded transmission below, simulates a moderately weak-signal HF DX path that follows a 14000 Km Great-Circle path over the polar region with a moderately disturbed ionospheric condition... There is deep QSB, tonal distortion due to pitch dithering, manual keying using a straight key resulting in a slightly variable weighted character stream, etc... This is as real as it gets. TRY to copy it ALL...


25 WPM using Straight Key manual keying
Deep, slow QSB,
Great Circle Polar path with Auroral pitch dither distortion




Could you copy all of it? Probably not in entirety... That's OK...

Some might have tried to use software decoders. In all probability they failed miserably... All other genuine CW operators who attempted to copy by the ear, here is how you could realistically assess yourself...

  • More than 90% copy in one go - You are truly a MASTER of CW Radiotelegraphy... My Respects.
  • More than 50-70% copy in one go - You are pretty good but maybe a bit rusty. Practice to sharpen your skills
  • Could copy a few sentences at a stretch - You can copy CW, no doubt. However, You are very rusty and mental fatigue sets in quickly. You need to seriously practice.
  • Could copy only a couple of words in succession - You have the basic underlying skills. But you tend to lag behind the transmission rate and hence loose it after a few words... Practice at 25 WPM, preferably using Farnsworth method.
  • Could only copy occasional alphabets but not complete words - You learned CW the wrong way. You tend to mentally break the characters into dits-n-dahs and do not register them in your mind as a single and homogeneous character sounds. You have hit the speed barrier which can only be overcome be following a proper code learning process... Follow my Morse code lessons that will come up very soon on this website... Stay tuned.
  • Could not copy anything. It all sounded so alien - That's very good. It means you have clean slate. You are therefore in a position to learn CW in the proper way from the scratch, if you try... Comprehensive CW lessons are coming up on this website... Stay tuned.


Hope you enjoyed the exercise... 73, de Basu VU2NSB

Started by Basu (VU2NSB) - Last post by Basu (VU2NSB)

Here are a few important pointers for those who live in the following specific regions and might like to take the challenge of negotiating propagation tomorrow and join the IDX Net on HS4.

The effective SSN has plummeted since yesterday and is expected to reduce further during the duration of the net tomorrow.... Hence, please keep the following in mind.

(1) Operators living in most of Asia, EU, Africa, East-coast of USA, East-coast Canada and central Canada, Caribbean, Mexico, Central America, entire South America except east and central Brazil, and most of Oceania region will have NO PROBLEMS... It should be a cakewalk.

(2) Those in USA and Canada should keep in mind that at the beginning of the net, the east-coast regions will have access. However, with the passage of time, the propagation into states and territories further westward will start opening up. Half way through the net and till the end, the states like Minnesota, Iowa, Dakota, Nebraska, Kansas, Oklahoma,, Texas, New Mexico, etc will manage to access the net... Further down the time, towards the end of the net, stations in Montana, Wyoming, Colorado, Utah, and Arizona should be able to make it, but the caveat is unlike the rest of the USA operators who need only moderate gain antennas to work comfortably into the net, they will require very high gain antennas like the stacked Yagi.

(3) The USA states of California, Nevada, Idaho, Oregon, Washington, Alaska, and Hawaii have practically NO CHANCE due to adverse propagation.

(4) European part of Russia should be able to reach and access the IDX Net during the first half of the session. However, the propagation might close down rapidly for them as the time goes by. Asiatic Russia, Korea, and Japan is not expected to access the net at all.

(5) UK faces a very unique situation vis-a-vis the net-controller's QTH. Almost the entire UK region falls within what is known as the 3rd Skip-zone... This phenomena is a rather unique one. As a consequence, as the earth spins on its axis and New Delhi (VU2NSB QTH) goes into darkness at nightfall, the propagation in the 3rd Skip-zone begins to fail much before the band closes down for the rest of the neighboring regions... Therefore, stations in UK might experience signal loss before the rest of Europe does so.

(6) Finally, our friends in the Tasmania region of Australia might find the conditions rather hostile and unsuitable for almost the entire duration of the net. Although, during the beginning of the net, it will be fine, but as the time progresses the south coast of Australia will begin to loose IDX Net access.... Rest of Australia is expected to come in with strong signals... New Zealand might also lie at the cusp of propagation for a substantial duration of the net. The northern half of New Zealand should do fine but the southern half might struggle.


73, de Basu VU2NSB.

Started by Basu (VU2NSB) - Last post by Basu (VU2NSB)

IDX Net Announcement!!! - Another Worldwide HF Radio Net Session on Wednesday, 03 March 2021 on HS4

We know that it could be a tall order during the low solar-cycle phase to conduct HF radio net that covers a large portion of the globe simultaneously to span over almost all continents... Nevertheless, India DX Net (IDXN) after due diligence has decided to run the third session since the commencement of this new solar- cycle #25 that has just begun.

On Wednesday, the 3rd March 2021,, starting at around 12:30 - 13:00 UTC, we will run the IDX Net on HS4. We will decide the operating band just before the beginning of the net session based on prevailing propagation conditions...

The objective of the IDX Net session is to dispel the false notion that the HF propagation conditions are poor and also to provide opportunities for everyone to participate in extreme DX communication. The Net will endeavor to be in constant and simultaneous contact with stations from all around the world including, Europe, Asia, Africa, Australia,, New Zealand, Caribbean, and parts of North & South America which poses the biggest propagation challenge for the Net Controller with the QTH in India. Therefore, the participation of operator's from west-coast of NA will probably not be possible, while the east-coast and central USA and Canada should be easy. The net might not be accessible from most parts of South America because the sun will be overhead in the South Atlantic region resulting in a strong ionospheric D-layer producing unacceptable signal attenuation.

The IDX Net controller will maintain continuous contact will stations from all across the world at the same time without missing a beat or swinging his antenna around... Join us from from all across the world and be a part of the magic... And also experience and learn more about the finer aspects of HF radio propagation.

To access a wealth of information and learn more about HF radio propagation, antennas, and other amateur radio related stuff on a continual basis, join our regular net sessions on Mon, Wed, Friday on HS3 at 12:15 UTC on 28.455 MHz and also join the IDX Net Facebook Group at...

https://www.facebook.com/groups/HamSphere.IDXnet.HF.radio/


73, de Basu VU2NSB (Net controller IDX Net)

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