NE-FL D-STAR System

The Journal of the North East Florida D-Star Repeater Network

Archive for category HF Antennas and Operation

Shorai LiFePO4 Batteries – the Cat’s Meow..!

Oct 31

Posted by mikelee in Go Kits, HF Antennas and Operation, Kit Construction | No Comments

 

The bane of amateurs who participate in PORTABLE emergency services communications has always been the source of 12VDC power – specifically that of batteries. They are ugly, messy, HEAVY and oftentimes unreliable if not maintained correctly. My biggest problem with lead-acid batteries has always been the sheer weight associated with them, followed by constant issues with proper maintenance, leakages, etc, etc, etc…

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Like most, I progressed from lead-acid marine, deep-cycle batteries to the AGM technology – most commonly sold under the brand-name of Optima, under their Blue-Top label. These have been excellent in every way… EXCEPT in the weight department. Also, since they are “spriral-wound”, the “cells” are actually cylindrical (as evidenced by the battery case, with 6 separate and distinct cylinders). From a power density standpoint, cylindrical cells are always less dense than cells that are made in rectangular fashion.

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Stepping up from AGM, the next logical choice was Lithium, the first form which was LiIon – but this technology had significant problems in the area of high-current explosions, since the lithium batteries would provide as much as 100C of current, while heating to the point of spontaneous combusion  - 1C equals the rated Ah of the battery, so if the battery was rated at 2A, it could potentially provide as much as 100A of instantaneous current – easily enough to weld metal (including the battery itself). LiPO batteries were somewhat better, but charging technologies were both expensive and unique. I never used LiIon or LiPo in anything except my electric RC Helicopters (Trex-450 and 700, for those of you initiated in the subject).

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The newest technology is called LiFePO4 – a chemistry of Lithium, Iron and Phosphate – which has the best characteristics of a battery yet to be found.

  • First, it is LIGHT – on average 1/3 the weight of an AGM battery of comparable AH capacity. A 14AH battery weights 1.6 pounds (compared to over 6 pounds on AGM or lead-acid).
  • LiFePO4 batteries are very safe – both electrically and environmentally. Although they can still deliver high current, most have protection circuits built-in to limit current charge and discharge to safe levels. LiFePO4 batteries do not get hot like the old LiPo or other technologies.
  • Charger technology has improved immensely such that most of the major battery manufacturers are also making companion chargers for a very reasonable cost.
  • The batteries are very, very small compared to their AGM or lead-acid counterparts – about half the size, due to their energy density.
  • The new LiFePO4 batteries are NOT cylindrical, but prismatic – in that they are flat cells with no curved surfaces – this allows them to be packaged in very high density packages and fit into “conventional” compartments.

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These batteries are great, but they’re not cheap.. the 14AH version which weights 1.6 pounds is about $155 plus minimal shipping. You’ll need the special charger for it – which adds another $75, but you’ll only need ONE charger. I have two of these batteries and they’re in the Go-Kits and they’ll only need to be “topped-off” about every 6-9 months, since the internal resistance of these batteries is so low (they’re rated 90% after 1 year, assuming standard temperature and full-charge before storage). The shelf life is pretty amazing.

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I’ve made it convention to replace or charge all critical batteries such as smoke detectors, go-kits, flashlights and the like on my birthday – just kind of my personal routine, as part of my celebration of another year and hopefully another up-coming year.

 

SO2R Controller – MicroHam MK2R+

Oct 5

Posted by mikelee in Antennas, Feedlines and Duplexers, HF Antennas and Operation, NET Operations | No Comments

This is a VERY cool device..!! Any of you looking to do SO2R, or to just have a single interface capable of handling two radios should consider this device.

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As mentioned in the SO2R blog entry a few days ago, this unit, commonly called the MK2R+ contains two Sound Cards, and all the audio and switching infrastructure to handle two radios while also receiving and relaying radio data (frequency, mode, etc) to the computer for the logging program. The magic of all this is that the MK2R+ uses a SINGLE USB PORT to your computer, so you don’t have to fiddle with 2 external sound cards, plus numerous USB-to-Serial adapters in order to talk with each of the radios, the rotator, antenna switches, etc…   Everything is contained in a single box – plus the MK2R+ also talks (seamlessly) to the MicroHam Station Master, as well as the Station Master Deluxe which will be released soon.

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Okay – many top SO2R operators use this device to handle the route audio and switching chores for their contest stations – granted. But I’m going to use it for routine, day-to-day operating as well as contesting. The Big-Guns often have 2 radios, but as many as 10 antennas, constantly (auto) switching antennas between the two radios, as well as bandpass-filter and various other gadgets. My set-up is much simpler – as are most of the folks out there who might join an occasional contest, so I will mostly use the audio switching functions of the MK2R+ as well as the built-in sound-cards for CW, RTTY and PSK.

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Set-up of the MK2R+ is very easy – well, sort of.. The hardware set-up is made simple due to the fact that two pre-built radio cables come WITH the unit. You select the radios that you want to interface – and cables are available for almost all of the major brands and models. In my case, we specified a cable for each of the Elecraft K2 and K3 – with specific connectors for the Rear Panel of the K3, so that all the cables would be out-of-the way and not facing the operator. The cable sets are beautifully constructed – very professional and each cable is labeled as to function and corresponding connection point on the respective radio – simplicity itself.

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The software setup is a bit more complex – and more time consuming. It’s worth-while to read the manual TWICE even before receiving the hardware – and again with the hardware connected. There is a piece of software call the uRouter (microRouter) that is the brains connecting the single USB interface to all of the functions contained in the MK2R+, as it emulates all of the serial ports that would otherwise be connected to a computer – such as 2 serial ports for the two radios, 2 serial ports for the radio CW keying lines, etc.. on last count, the uRouter software was emulating over 9 serial ports into the USB connection and doing a flawless job of it (on top of talking to both of the MK2R+ sound card interfaces). This is a very complex piece of software, but it simplifies SO2R by an order of magnitude or more – not to speak of making a VERY CLEAN looking station (no wires all over the place).

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Computer software that takes advantage of SO2R and the MK2R+ specifically includes all of the popular contest software like N1MM, TR, WriteLog, CT and NA amongst others. I’m only starting to get familiar with the WriteLog piece, but initial impression is that it’s very slick indeed..!!

Cost for the MK2R+ is right at $995(price increase in the last 30 days) and it ships from the US Distributor direction in Geneva, Florida. Two radio cable sets are included and extras are $75 for any model radio. Sure, the set-up sounds steep, but when you consider that it includes 2 sound cards ($99 each for the SignaLink), 2 cable sets ($75 each), no need for 2 USB-to-Serial adapters ($35 each), you’ve saved $450 in other costs right there, so that makes the MK2R+ about $550 for the audio switching capability and other essentials to make SO2R work seamlessly.. pretty effective given that it cleans-up the radio table of all the separate units, wall warts, cables and miscellaneous “junk”….   I’m sold..!!

SO2R – Single Operator 2 Radios

Sep 30

Posted by mikelee in HF Antennas and Operation | No Comments

A term I had not even heard of until recently – primarily meant for contesting, but applicable for anybody who has 2 HF radios and wants to maximize usage of both at the same time. SO2R is a technique of managing two radios with a single computer and audio interface (1 set of headphones and 1 microphone or boom-mic). I got interested in the technique in order to monitor two BANDS simultaneously, or while calling CQ on one radio and listening for band openings on another band with the 2nd radio.

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My interest in SO2R stemmed from the fact that I have an Elecraft K2, along with a full-house Elecraft K3. Each now has an amplifier, so each can be a fully capable QRO station – yet, I only have 1 microphone and 1 set of ears. SO2R, using the appropriate hardware and software, will allow me to hear the K2 in my LEFT ear, whilst the K3 is in my RIGHT ear. The microphone or boom-mic will follow the radio which needs to transmit, based on computer software settings (I’m using WriteLog for contests). It’s all made seamless with the right equipment and software, but here’s an example of what can be done (my plan) :

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Let’s use the example of the K2 on the LEFT and the K3 on the RIGHT. The K2 has an Alpha-99 legal-limit amplifier connected to it, so we’ll use that radio as our RUN radio and try to “own” the frequency for some period of time due to high power and a good antenna. The K3 only has 650w (only.. :D ) or nearly QRO, so we’ll just use it for search-and-pounce.

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The SO2R controller has a built-in Sound-Card interface for each of LEFT and RIGHT radios. We pre-record  a set of contest exchanges in the left side for the K2 – such as : “CQ Contest, CQ Contest, CQ Contest – this is WB6RTH calling CQ and standing by”  - but we also have responses like “Roger, 59 Florida, 73′s” or whatever the contest exchange needs to be. We then have the SO2R controller “play” the recordings as necessary, such that human intervention is hardly ever required during the contest (except for unusual exchanges). This allows us to concentrate on logging the station (call-sign only, since the SO2R controller transmits all of the frequency, mode, power and other radio information to the logging software). Aside from logging, we would be listening for DX or band openings in the RIGHT ear, using the K3 – and if a multiplier was found, pounce on it with 650w of SSB or CW power.

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In normal situations, having both radios online and in different ears would maximize chances of running into DX, since we’d be listening to multiple bands at the same time. Oh – in case there’s any concern about transmitting and receiving on the same band (or harmonics), the SO2R controller automatically prevents that, since it always knows the frequencies of both radios – and will inhibit PTT if the adjacent radio is on the same band. Most of the better controllers can also control Bandpass Filters, as well as other peripheral controllers and equipment – at a cost, of course.

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I’ll be SO2R in the next few weeks, using the MicroHam MK2R+ controller and will write about my experiences during October. The MK2R+ is the BMW of SO2R controllers in that it has a SINGLE USB interface to the computer, but has 2 Sound cards, radio interfaces for two radios and can do CW, PSK, FSK, RTTY and Voice simultaneously – remarkable.

Elecraft KPA500 – Build Report

Sep 27

Posted by mikelee in HF Antennas and Operation | No Comments

WOW….!!!  Another great product from Elecraft – this time, an HF amplifier rated at 500w CW but which actually goes to 650w easily without any significant IMD increase.

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This “kit” was received in a single box, with the typical Elecraft care in packaging. The largest component was the toroidal transformer which weighs-in at about 15 pounds and which contributes to the majority of the overall 26 pound completed unit. Everything went together without a hitch – there are no super-tight-clearances involved in this kit, so if you get one of these units, take your time, go slow and enjoy the build process.

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I completed the build in about 5 hours – at a casual pace. Started at about 4pm after my last conference call of the work-day and completed by 9:30pm with a quick dinner break in-between. The unit powered-on on the first try and passed all of the routine start-up checks. High Voltage reading was well within the normal parameters at 76v and all the band-switching worked flawlessly as expected.

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Unit can be operated on 95-245vac – switching from 120 to 240 is easy – simply change the position on the switch and you’re ready to go. If you have non-standard voltages (under or over-voltage), adjustments in the inside transformer taps will be required, but it’s both easy to accomplish, and simple to understand.

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Elecraft KPA500 front panel – clean and all automatic, currently on 60m

Entire unit is the size of the K3 and weighs 26 pounds

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Update – Day-2
Had the opportunity to get back to the KPA500 this afternoon and was able to test the new MAC software for the KPA500. Worked flawlessly, as in all of the software that I’ve used from David Fleming (he writes software for Elecraft). Was able to check the firmware versions, as well as download the most current version of the KPA500 firmware and change any of the parameters on the KPA500. Also did the full transmitter integration test with the K3 this afternoon – using a purchased KPAK3 cable (crazy to make one yourself, considering how inexpensive the cable is from Elecraft). Works like a champ. One thing unexpected – the ACC cable between the K3 and the KPA actually signals PTT, so there is no separate KEY line required (unless you’re NOT using the ACC line). Obviously, there are some cases where you might actually WANT to use the key-circuit – in that case, Elecraft provides a mod (an “interrupter”) which disconnects pin-10 of the ACC cable so that you can use the external KEY circuit. A curious tid-bit of information.

N6BT – “Array of Light” Book Review

Sep 20

Posted by mikelee in Antennas, Feedlines and Duplexers, ARES Training, HF Antennas and Operation | 3 Comments

I had the pleasure of meeting Tom Schiller (N6BT) last weekend at the Torrance Hamfest. Tom is the co-founder of Force-12 Antenna Company (along with his dad) before selling it after many years to a Texas company. Tom now has a new line of antennas under the company N6BT.COM that appear to be outstanding, yet economical at the same time. I’ll be reviewing some of his designs in the next few months, but in the meantime, I purchased his latest book called “Array of Light” – Straight talk about antennas and related subjects.

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Now what makes Tom unique, is that he doesn’t live in the theoretical world – he’s a a master antenna designer, having designed some of the most successful antennas for the commercial, amateur as well as military market. Although he uses computer modeling, Tom actually constructs and measures antennas of his own design and has been tweaking designs for over 25 years. His designs are in use all over the world and he has a very large following of DX chasers.

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I spent about 45 minutes talking with Tom, since I was curious about his antennas, as well as his latest book. I have to tell you, the book is almost an inch thick in a spiral binding and is LOADED with great information. Now I’m no antenna expert, but I’m also not a complete idiot either  - but I have to tell you that his book is FULL of great information.  There are 54 chapters in the book, with subjects ranging from “Efficiency” to troubleshooting antenna problems, to construction techniques. Virtually anything you would ever ask an expert about building, installing, using and maintaining an antenna system is covered in this book.

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Oh  - did I mention that Tom is an avid DXpeditioner..??  Tom and his crew at Team Vertical have many years of foreign travel to exotic places, shlepping all kinds of radios and aluminum for contests – and the team has a number of World Records to their credit – one of them while operating QRP..!!

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I’m not but half-way thru this book – but so far, it’s TOP NOTCH… HIGHLY RECOMMENDED..!!

Elecraft P3 Pan Adapter – Upgrades

Sep 15

Posted by mikelee in HF Antennas and Operation, Kit Construction | 2 Comments

I learned from Eric the other day that the Elecraft P3 Pan Adapter is about to get some upgrades that ALL of us have been looking forward to – in fact the rear panel of the production unit already had the connector cut-outs punched, waiting for the electronics and firmware to arrive.

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The Pan Adapter SVGA display cards are just finishing final test and will be going to production very soon – which will give the P3  a number of great capabilities, including :

  • an SVGA port which can connect to an external monitor to give 1280 x 800 resolution (non-interpolated from the P3 native screen) – this means higher resolution from the DSP, not just res’d-up from the P3 LCD.
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  • The P3 will decode CW, RTTY and PSK (just like the K3 on the scrolling, ticker-tape display area of VFO-B, but ON THE EXTERNAL SCREEN..!!
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  • The Display adapter will have provision for a USB keyboard, so that you can have a digital QSO thru the P3 to the K3, without the need for an external laptop (except for logging, of course). During the QSO, your laptop will already have all the relevant radio information (frequency, mode, etc) thru the connected serial port (as usual).
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  • a number of other firmware upgrades will be released at the same time
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The Display adapter will use a custom graphics chip – which Elecraft was able to secure in reasonable  quantities (unlike the PC-graphics manufacturers who only take orders in the multi-hundred-thousands as a minimum), but the custom chip also allowed them to insert features that were important to Elecraft, not just the PC industry.

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Pricing is expected to be in the $350-400 range – very reasonable, when you consider that you just gained a large-screen for the pan-adapter and a full function digital encode/decode station..!!    I’ll be on the waiting list, as soon as it’s open for orders..!!

Elecraft KPA500

Sep 11

Posted by mikelee in D-Star Users, HF Antennas and Operation, Kit Construction | No Comments

Additional Note (12-Sept) – for those of you who have thought about EME on 6m, this might be the perfect amplifier… coupled to a single antenna and using WSJT, realistic EME might be possible. We’ll try and report back in another segment.  Or… how about high-power 6m DSTAR..?? It’s legal… yet another thing to try..!!

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okay… color me crazy, but when I’m on a roll there’s nothing that can stop me.

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As all of you know, I’ve completely gutted my HF station of Yaesu, Icom and Kenwood equipment (with the exception of EMCOMM-1, which will continue to have Kenwood equipment (TS-570 and TS-480). But the home stations have all been converted to Elecraft. Sorry… just remembered that I still have an IC-7000 for the car, as well as a Yaesu FT-100D for the bus…. but you get the picture..

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I am in love with the philosophy of the Elecraft company and how they release hardware products, firmware and software – and how they treat their customers. Wayne Burdick (N6KR) and Eric Swartz (WA6HHQ) are very involved in soliciting user feedback and requests, even though they are the founders and owners of the company. I see Wayne and Eric on the email reflector virtually every day, answering questions, providing advice, engaging in discussions and nurturing the community that they’ve built. The community of Elecraft users worldwide is the tightest-knit group of amateurs that I have ever seen. In many cases, I’ve had questions and have either found the exact answer on the nabble.com reflector that Elecraft wisely created long ago, or have made an inquiry and received an accurate response within 24 hours (often within a few hours). An individual in Wake Forest (W3FPR – Don) has been an absolute gem – giving advice to folks around the world, as a genuine world-class expert on the K1, K2, KX1 and even the K3 line of products. Don has even helped me on a number of occasions, having worked on both my K2 and my KX1 – reviewing my construction technique, making suggestions and correcting mistakes I might have made – he’s a wonderful resource and I’m most grateful to have access to him (at a very reasonable cost, I might add). Most of these individuals do it because they are passionate about the product and more-than-willing to share their experiences and knowledge – I love that attitude.

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I was able to see the (relatively) new KPA500 solid-state amplifier the other day – amazingly it’s exactly the same size as the K3 and only weights 26 pounds with the built-in power supply. Although the name connotes that it’s rated at 500w, that’s actually the Minimum power. Most folks are getting in excess of 650 and the firmware appears to limit at 700 in order to preserve the IMD characteristics of the unit. Let’s see – if we use 650w as a realistic number, that means that the unit is only about 4db below full legal limit of 1500w output – but remember, it’s TWENTY-SIX POUNDS… unlike either of my Alphas, which tip the scales at over 70 pounds EACH. Unless you’re an organized DXpedition, lugging around an Alpha-99 or Alpha-87A would be impractical (especially since you’re really supposed to remove the transformer, which ALONE is about 45 pounds). By contrast, I could easily pack the K3/P3 combination in my carry-on luggage (total of about 13 pounds), and pack the KPA500 in a roll-on Pelican case as check-in baggage (total of about 35 pounds, but ON WHEELS). The Pelican could also transport the power supply for the K3/P3 combination, as well as feedline, connectors, Wire Antennas, etc.  Another case would house constructible antennas like a HexBeam or the BuddiPole system, or the new antennas from N6BT (Tom Schiller, of former Force-12 and Team Vertical fame). Tom’s new antennas are killers – and we’ll be reviewing some of them in the next couple of months.

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So the KPA should be arriving this coming week – and as in all other Elecraft kits – should come together like a dream. At $2,000 for the kit (which only takes about 6 hours to assemble), it has got to be one of the most reasonably priced solid-state HF amplifiers out there, but even more importantly, the integration of the KPA500 with the K3 is really outstanding. The two form a SEAMLESS 500 watt RADIO SYSTEM – with full bi-directional communication between the boxes – truly superb engineering.

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The KAT500 Auto Antenna Tuner (companion to the KPA500) should be out by early 1Q2012 (possibly sooner, according to Eric). Like other Elecraft tuners, it will handle 10:1 SWR on most bands, will be 160m-6m and will be able to handle 1kw+ power after tuning all day long. I’m looking forward to getting the KAT500 when it becomes available. According to Eric, the price will be competitive with other vendors’ models in the same Power Range (I actually mentioned a pretty tight price range and he concurred, but I should allow him or Wayne to announce, since that information was gained in a private conversation and things are always subject to change when you’re 3-5 months out from product availability). The KAT500 is in engineering test now and they’re still “tuning” the firmware (pun intended), although much of the logic and algorithms have been taken from the time-proven KAT100 and other tuners they’ve been manufacturing for years now.

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Next week – we’ll talk about the new upgrades to the P3 PanAdapter – these will rock your world, if you have a P3, or if you are contemplating the purchase of a P3. And remember, the P3 works with ANY radio IF frequency (you specify).. it can also work as a Spectrum Analyzer (if you know the secret.. :D )

 

Adjusting IF Filters – the WYSIWYG Way

Aug 30

Posted by mikelee in HF Antennas and Operation, Kit Construction, Test Equipment | No Comments

I’ll bet that most of us have never actually known how to adjust or “tune” the IF filters in our radios, regardless if HF/MF or VHF/UHF. All I was exposed to was to tune for best match to my EAR – if it sounds good, then it’s good enough..!!

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Although true – and certainly everything has to (eventually) pass to our ears, there may be a better way to be able to understand how filters respond – and to take advantage of their characteristics in ways that we’ve never experienced in the past. Also take into consideration that the new digital modes will be able to “hear” even below the noise-floor  - so the ear may no longer be a factor in the near future (or current). I used the following technique when I needed to adjust the bandpass characteristics of the Elecraft K2′s IF filters. It was quick, easy, highly visual and very accurate.

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The technique starts with injection of broadband, but stable (consistent) noise into the front-end of a receiver. For this, I used the Elecraft N-gen – an inexpensive, yet very useful tool that provides a noise signature that is within 3db from 100khz to 500mhz, it’s useful for all our radios to lower-UHF. The unit comes as a kit (typical Elecraft) that is very easy to assemble and has a single ON-OFF switch and a BNC-F connector for it’s output. It’s stand-alone, powered by a single 9V battery. You simply connect the N-gen using a short BNC M-to BNC-M cable, or a simple BNC-MM adapter works nicely as well. Turn the N-gen ON and you have a noise source being injected.

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The next part requires a laptop with a microphone port to the sound card, as well as some software, as we’ll now be looking at the AUDIO that results to the external speaker port of the radio (an Elecraft K2, in my case). Fortunately, most radios have standardized connectors – most HF radios use 1/4″ phono plugs, while more compact radios use the 3.5mm stereo plug. Coincidentally, most laptops also have a 3.5mm stereo receptacle for mic-INPUT (as well as output), so it was a simple case of having a short 3.5mm male-to-male stereo cable to make this test between my MacBookPro and the Elecraft K2 (about $4 at Fry’s or other similar stores).

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Software for the Audio Spectrum Analyzer comes in all flavors, as well as prices. Although we could have used many VERY expensive tools destined for the professional sound industry, there are a number of Freeware packages available.

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The technique is as follows :

  • Connect the audio OUTPUT from the radio, to the sound card INPUT (Mic-input in most cases) of the laptop.
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  • Start Spectrogram or iSpectrum, depending on your hardware platform.
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  • You should see a representation of the radio audio-output on the screen – if not, switch to the other channel (left, or right).
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  • Once you’re able to see the signal displayed as a moving graph on the screen, narrow the bandwidth of the audio sweep from a low of ZERO, to a high of about 2.5 or 3 khz. This will focus our analysis on that portion of the usable radio audio spectrum.
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  • Now start adjusting a single parameter of the current IF filter and watch the response on the Audio Spectrum Analyzer – you’ll see the noise move from left to right. If the filter is operating, you’ll see cut-off either on the left-side (low cut) or on the right-side (high-cut). In some cases, you might see both sides cut-off, signifying that you’ve engaged an IF bandpass filter.
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  • Okay… now we understand cause-versus-effect. We’ve made a change thru one of the controls, then SEEN the effect of that change to the audio spectrum. Remember the N-gen generates broadband noise that is quite uniform across the spectrum of 100khz to 500mhz – to within 3db (about 1/2 of an S-Unit), so what you see, is pretty-much what you get (remember that the human ear can only distinguish about a 4db change in sound volume – best case).
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  • Time for some real alignment – I’ll use the  8-pole CW filter that has a bandwidth of 400hz. In this case, we want the (passed) noise to be dead-center on the our SideTone frequency (600hz in my case) so I’ll set a marker at 600hz. We want the noise to be centered here – with equal fall-off on both sides of the 600hz marker.
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    Let’s start with a wider filter, so that we “zoom” into the target bandwidth – here’s the progression :

  • Above is actually of a fairly wide-band CW filter (1.0khz).. 


    Above is from a 400hz wide filter – notice that the skirts only go about 200hz on either side of the 600hz marker line…

  • SSB filters (or anything non-CW) have a broader bandpass, so instead of aligning to a center frequency like in CW (at the side-tone frequency), we normally try to align the filter to be centered BETWEEN two frequencies (low-and-high limits). The standard objective is to get as much of the received noise to be within the low and high cut-off points as possible – and not have some of the signal ‘roll-off” either the high, or the low ends.
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    Above : an example of an SSB filter that is biased too far to the low-side – while this might be good for low frequency fidelity, it will compromise high frequency response – an area where most of the consonants are in the English language. 


    Above : a better aligned SSB IF filter that keeps most of the signal within the limits of the filter bandwidth.

Elecraft P3 – PanAadapter

Aug 26

Posted by mikelee in HF Antennas and Operation, Kit Construction | No Comments

We ordered the Elecraft P3 Pan-Adapter along with the full-house K3. Construction was a snap – with everything coming together easily as expected. The unit is in true Elecraft style, as construction techniques are all very familiar to those who have built the K3 and K2 lines of radios.

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Many people might think (reasonably) that the P3 is ONLY for the Elecraft radios, but that isn’t true at all. The IF is adjustable on the front panel menu system, as are RS-232 interface parameters, so you could theoretically use any radio.

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Okay – why the P3..?  In my case, because it was part of a matching set with the K3 and KPA500, but the other reason is that it is a STANDALONE unit – and does not require a PC or display screen. Future upgrades (reportedly) will allow for connection of an external screen directly to the P3 (very cool).

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Those who have used a Pan-Adapter know it’s usefulness in chasing DX when they’re operating on split. This unit fills the bill very nicely – and at $700 for a fully contained unit, it’s a steal..!!

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Above : The P3 with my K3 radio

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Above: the P3 unit, with a small waterfall

Elecraft K2 QRP – Full House

Aug 24

Posted by mikelee in HF Antennas and Operation, Kit Construction | No Comments

It’s complete – the full-house Elecraft K2 with every available option, in QRP configuration and checks-out at about 15 watts on all bands. Since the original construction, we’ve also added the KIO2 option to give us serial I/O capability to talk with the computer, as well as to communicate with the 100w Amp/Tuner combination which I installed in a separate matching-box.

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I chose this approach so that I could keep the K2 as a full-featured QRP rig, including the internal battery and QRP Tuner – making a great grab-and-go unit which weights barely more than 5 pounds. Inside the unit are the following:

  • K2 base unit
  • SSB option
  • Noise Blanker
  • DSP unit
  • 160m option
  • 60 meter option
  • internal battery
  • auto tuner
  • serial interface

Wow.. what a great configuration..!!  The QRP configuration, coupled with a BNC-to-Binding-Post adapter allows for a simple antenna to be connected and the radio to be on-the-air almost immediately. Two lengths of ultra-thin, almost invisible wire and you’re operational with minimal fuss and a great signal. The built-in QRP tuner in the K2 allows for all-band operation. Internal battery operation allows for CW operation for in excess of 8 hours without recharge (remember, the K2 has a receive current draw of only about 125-200ma).

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Shown side-by-side with the external Amp/Tuner combination.

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