AmateurRadio.com

 

Some snow removed from side to have access

This year we have been getting our share of the snow as it seems each week they are forecasting storms with up to 60cm or snow. As a result the snow has been piling up around the property including the shed. The shed is where one end of my End-fed antenna is secured too. The wind seems to blow in a way that causes the snow to drift along one side of the shed. I began to have some SWR issues with the End-fed antenna nothing the antenna tuner was not able to deal with but I wanted to check out why. It seemed the snow drift now well over 9 feet high was getting very close to the End-fed wire and affecting the SWR.

The solution was easy, it was time to get the snowblower out to the shed and blow the snow far far away. With that done the End-fed antenna was happy and so am I. Seems I have to keep an eye on the shed regarding drifting snow. With just a small bit of shovelling here and there this issue will not be a problem again. 

All done.

This brought another question to mind.....I was thinking of getting a vertical antenna maybe the Hustler 4BVT.  But I am now looking at this again as I see this being a high maintenance antenna when the winter comes trying to keep the snow away for the base.

Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].

 

Some snow removed from side to have access

This year we have been getting our share of the snow as it seems each week they are forecasting storms with up to 60cm or snow. As a result the snow has been piling up around the property including the shed. The shed is where one end of my End-fed antenna is secured too. The wind seems to blow in a way that causes the snow to drift along one side of the shed. I began to have some SWR issues with the End-fed antenna nothing the antenna tuner was not able to deal with but I wanted to check out why. It seemed the snow drift now well over 9 feet high was getting very close to the End-fed wire and affecting the SWR.

The solution was easy, it was time to get the snowblower out to the shed and blow the snow far far away. With that done the End-fed antenna was happy and so am I. Seems I have to keep an eye on the shed regarding drifting snow. With just a small bit of shovelling here and there this issue will not be a problem again. 

All done.

This brought another question to mind.....I was thinking of getting a vertical antenna maybe the Hustler 4BVT.  But I am now looking at this again as I see this being a high maintenance antenna when the winter comes trying to keep the snow away for the base.

Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].

In this episode, Martin Butler (M1MRB) is joined by Chris Howard (M0TCH), Martin Rothwell (M0SGL), Frank Howell (K4FMH), Bill Barnes WC3B and Leslie Butterfield G0CIB to discuss the latest Amateur / Ham Radio news. Colin (M6BOY) rounds up the news in brief and in the episode's feature HamPi. We would like to thank Daryll McCathery (VK6DMC ), Mr D Renton, Appledore and District Radio Club and our monthly and annual subscription donors for keeping the podcast advert free. To donate, please visit - http://www.icqpodcast.com/donate

• Rye Man Convicted for Making Racial Remarks over Amateur Radio Networks
• Foundation Online Training Course Statistics
• Parks on the Air Radio Ham in the Press
• FreeDV Activity Day
• Pilots Fault Electronics "Spoofing" of GPS Signals
• Platinum Jubilee NoV Now Available
• Beijing Winter Olympics Special Event Station BY1CRA/WO22 is Active
• ARRL Announces New World Wide Digital Contest
• GB100 2MT marking the Centenary of British Broadcasting
• Inventor of APRS, Bob Bruninga W4APR is SK

Colin Butler, M6BOY, is the host of the ICQ Podcast, a weekly radio show about Amateur Radio. Contact him at [email protected].

One of the most useful electronic test tools available to us is the digital multimeter (DMM). There are many different models to choose from but for less than $50, you can get a decent quality meter that measures DC and low-frequency AC voltage, current, and resistance. Using such a meter, with auto-range capability, is pretty much a matter of selecting the desired measurement function and connecting up the test leads. It is a really simple, but effective measurement device.

So where is the radio frequency (RF) equivalent of the DMM? There are some excellent multifunction RF/microwave instruments such as the Keysight FieldFox analyzer. But these professional instruments are much more expensive than a DMM and much more complicated. I am thinking of something that has the same Select-and-Connect usability of a DMM.

Low-Cost RF Instruments

In recent years, low-cost RF instruments have emerged that can make some impressive measurements. The first one that comes to mind is the nanoVNA, a compact vector network analyzer. There are several different models available but a typical configuration covers two-port measurements from 10 kHz to 1.5 GHz, at a price of around $70. The nanoVNA is quite capable, able to measure two-port s-parameters (reflection and transmission), return loss, standing wave ratio (SWR), etc.

More recently introduced, the tinySA spectrum analyzer offers basic spectrum analyzer measurements from 0.1MHz to 960 MHz. The cost is ~$60 and the SA includes a basic signal generator feature.

I own both of these devices and I think they are excellent instruments for the price. But they aren’t what I am looking for in an RF DMM. They do provide a proof point that simple and affordable RF instruments are possible.

Another device that has caught my attention is the Surecom SW-33 SWR / Power meter. This tiny meter is great for tossing into my SOTA backpack or radio Go Kit, to have some basic RF measuring capability in the field. It covers 125-525 MHz, up to 100 watts (with an appropriate dummy load or antenna), for less than $50.

But it only measures SWR and power. Not bad but not quite everything I’d like in my RF DMM.

Antenna analyzers are another category of affordable RF test equipment. As the name implies, they are focused on making measurements on antenna systems. Again, there are many different models to choose from, ranging in price from about $100 to $500. Shown below is the RigExpert Stick 230-K with a bit of a simple DMM look to it. The primary antenna measurement is SWR, but the antenna analyzers often include complex impedance, return loss, reflection coefficient, etc.

The RF DMM

OK, Bob, what is it that you do want in an RF DMM? Good question. Thank you for asking.

The device I have in mind should cover the common RF measurements that a typical radio amateur needs to perform. In terms of the use model, consider what is needed to check out a new radio installation, from the transceiver to the antenna. I want to be able to check the transmit power, the impedance looking into the coaxial cable, the SWR (and return loss) of the antenna system across the typical ham bands (160m through 70 cm).

So here is the wish list:

• Frequency Range: 1 to 450 MHz
• RF power meter (directional, inline measurement)
• RF power meter (with internal dummy load)
• Antenna measurements (SWR, Return Loss, complex impedance, other derived values)
• Frequency counter
• Basic signal generator (produce a sine wave at a particular frequency)
• Probably an N connector for ruggedness and good match at UHF frequencies. However, an SMA connector would have the advantage of small size and might be more appropriate.
• Price: <$50

I initially left out the signal generator but the antenna measurements will generate a test signal, so having a simple signal generator is not a big stretch and can be very handy. A couple of bonus features could be the measurement of FM deviation and decoding of CTCSS frequencies. I think these can be added at minimal cost but they are a nice to have feature, not mandatory.

I included an internal dummy load for simple RF power measurements. It is really handy to be able to check power level independent of the antenna system. This raises the issue of what power level it will support and for how long. It would be great to be able to measure 100-watt transmitters for a short period of time but that may be inconsistent with a low-cost, handheld device. A 5-watt dummy load should be easy and maybe a bit more…perhaps 25 watts? Of course, external attenuators can be used for measuring higher power.

It will be tempting to include frequency sweeps of the various parameters but simplicity should be the top priority, so the RF DMM probably only measures one frequency at a time. Leave out the fancy display, analogous to how a typical DMM does not provide an oscilloscope display.

It is also tempting to include standard DMM features in this device, so you’d have one meter that covers all of the basic ham measurements. Given the availability of inexpensive DMM integrated circuits, this would not be a big stretch. This would require separate DMM inputs (banana jacks). Perhaps skip the current measurement capability and just have DC/AC voltage and resistance? But everyone already has a normal DMM, so I see these features as optional.

The price point may be aggressive but the idea is to make it cheap enough that most radio amateurs own one, or several. Keep one in your Go Kit, one at home, and one in the car (similar to a DMM).

So that is my idea for an RF DMM. What do you think?

73 Bob K0NR

The post Where is the RF Digital Multimeter? appeared first on The KØNR Radio Site.

Bob Witte, KØNR, is a regular contributor to AmateurRadio.com and writes from Colorado, USA. Contact him at [email protected].

It's time once again for The Weekender. This is our bi-weekly departure into the world of amateur radio contests, open source conventions, special events, listener challenges, hedonism and just plain fun. Thanks for listening and, if you happen to get a chance, feel free to call us or e-mail and send us some feedback. Tell us how we're doing. We'd love to hear from you.

73 de The LHS Crew

Russ Woodman, K5TUX, co-hosts the Linux in the Ham Shack podcast which is available for download in both MP3 and OGG audio format. Contact him at [email protected].

 

If you like DXing the broadcast band, then the weekly ‘DX Central MW Frequency Challenge' may be of interest to you. It’s run and organized by Loyd Van Horn, W4LVH, a dedicated DXer and a big promoter of BCB DXing.

Basically, participants are asked to listen on the chosen frequency for a one week period and report what they have been able to identify. Results of course will be different throughout the continent but if you are near any other listeners, it’s always fun to compare your final results.

The new frequency (or frequencies) are announced Sunday evening around 0100Z on Loyd's regular live-feed Youtube channel as well as on his Twitter feed   @dxcentral 

Loggings are reported via a fill-in form which is updated weekly.

As well, information on most aspects of AM BCB DXing can be found on Loyd’s website.

Hopefully you can give it a shot during the week and see what you can catch. 

 

                               This week’s frequency is 1450 kHz.

Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

Hello and welcome to the 452nd installment of Linux in the Ham Shack. In this short topics episode, the hosts discuss ARRL grants, FreeDV Activity Day, the demise of TenTec, new WINE, new Ubuntu, IMs via ham radio and much more. Thank you for listening and have a great week.

73 de The LHS Crew

Russ Woodman, K5TUX, co-hosts the Linux in the Ham Shack podcast which is available for download in both MP3 and OGG audio format. Contact him at [email protected].