Back to Antenna’s

I think I have found the antenna for me going forwards. After playing with the half wave coaxial vertical antennas for some time, the only one that really worked consistently was the 10/11m version.  I could not get rid of the CMC’s on the 20m version no matter what I tried so have given up for now.  I went back to the inverted V but it was a hassle having to erect it and tear it down all the time. it was also a visual eyesore. The SWR would change based on height and angle and any nearby objects. I was always getting it tangled up so deployment took quite some time, not to mention needing 2 points to tie it off in addition to securing the base. But when in the air, it worked nicely and received quietly and transmitted well. Tried to add a 20m wire to the feed point of the 40m inverted V but neither antenna seemed to work as well, so gave that up. Consequently band changes meant antenna changes and more time wasted.

I was convinced a half wave vertical was the way to go for ease of deployment. The 12m telescopic poles stay up very well with just a light wire taped to them, I just needed to feed it correctly. Enter the 49:1 un-un.  This is what I bought. https://myantennas.com/wp/product/efhw-8010/
10-80m 1kw no tune on the various bands it is resonant on.
There are many other designs using a 9:1 un un but they require a tuner to get usable SWR to the radio. I didn’t want to rely on a tuner so did not look any further at them.
A European company making similar antennas using a 49:1 un-un can be found here: https://www.hyendcompany.nl/tech_info
Half wave verticals have always worked well on 10 and 11 meters and most did not incorporated much in the way or radials, so it stands to reason they would also work well on 20m (if we could get them up high enough.)

For 20m we can easily attain this with a 12m push up telescopic fibreglass mast. Half wave verticals do not require a complicated ground plane system like 1/4 verticals. It is not to say they won’t benefit from an extensive ground plane but they do seem to work well without much in the way of counterpoise or radials. They also work in all directions. No need to rotate.

The 80m wire (40m long) that came with the 49:1 Un Un feed box was way too long to use so I cut a 5.5m length of light weight 2mm insulated wire and started playing around with that on 20m. To get a low SWR I ended up trimming it back 9.15m. The SWR at 14.2mhz was 1.3 and did not rise above 1.5 at the band edges. According to the antenna analyzer the resonant frequency was 14.6mhz despite the lowest SWR at 14.2mhz. I also used 2 ea 2m radials and I think if I play with  these I can change the characteristics to bring the resonant frequency and the minimum SWR a bit closer together.

I noticed several things while using and testing this length of wire on 20m with the “My Antenna” 1kw 49:1 Un-Un. It is not a balun. Everything to do with this antenna is unbalanced! The performance improved remarkably once we got the feed point up in the air a few meters and out in the open. It does not like to be around other metallic structures or antennas or feedlines. It is also susceptible to noise and nearby radiation sources. I noticed a lot of bleed over from nearby AM transmitters when in AM mode. Fortunately there is a lot of information on the internet about these type of antennas: from those maintaining it doesn’t and can’t work, to those that swear by it. The truth is they do have their problems and one needs to be aware of them. Common mode currents is the big issue. I got rid of most of the noise by installing a 2″ round toroid choke at the feed point. Wound 15 or so turns of RG58 around it. That quietened things way down. Allowed me to stop using the attenuator to reduce the noise and got rid of the AM broadcast bleed over in AM mode. One website recommended a counterpoise of 0.05 wavelength. That comes to 1m for the 20m band so I need to play more with that to see what changes it actually makes.
I might also ground it at the Un-Un seeing it has a ground/radial lug and see what that does.

Another advantage is that it is resonant at any frequency that is a multiple of a half wave. So the 20m version should show resonance somewhere in 10m which it does. Unfortunately; just over 29mhz which ties in with the measured resonance at 14.6mhz.
So with a bit more work I should have a dual band no tune vertical.

Which has go me thinking…Spider beam do have an 18m push up telescopic pole advertised on their website. That is pretty well a half wave on 40m! Soo..40, 20 and 10m on one pole. I think I can do that. Just need to make a suitable mounting point against the house that I could strap the bottom section of a 60′ of tapered fibreglass pole to. A length of 6″ x 3″ treated pine should be enough.  20200117_091649[1]20200117_091723[1]20200117_113612[1]20200117_113716[1]20200118_164312[1]

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KL505V in Use

Took it for a spin in the car yesterday and gave it a good trashing on 20m on the ANZA Net. The Xiegu G90 was set for 10w SSB and the selector on the KL505V was on 6. The Average power meter reading was 150w to about 175 out. Depending on how loud I spoke. The Fans come on slowly the moment the amp is turned on and ramp up when the amp is keyed. Nice feature. The amplifier ran smoothly and got warm to the touch but no more. The voltage from the car battery stationary was about 12.4 volts and starting the car did not change the output level in any noticeable way.

AM test 5w carrier in  50w out, 10w AM in 100w carrier out. No worries there!
My 10w PEP input obviously was causing no issues and all audio reports were good.

So far so good. It works as it should and the fans do their job. A solid little amp for the job as usual. But remember: it has no shutdown circuitry or filters so try not to run it flat out cos if something goes wrong after the amp and you have no headroom, the amp will not shutdown till it breaks. I ran an in line swr meter after the amp and kept an eye on it.

I am talking average power with 10w SSB in. A whistle pegged the 200w meter.

I don’t think there is anything else out there for the price.

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RM’s KL505V with PTT Revisited

KL505V face

Having another look at the KL505V with Ptt which arrived from Italy recently. What is so special about the KL505V you may ask? Quite a lot.
I thought I would check it out on RM Italy’s website but it is no longer listed for sale.

Well ..
It is one of our more popular HF Amplifiers as it covers from 3.5 to 30 mhz and pretty much everything in between with quite decent input SWR’s.
Simple…No safety features except fuses (which may or may not work in time to prevent the finals blowing up if you connect the power the wrong way round.)

We asked for PTT to be incorporated into the amplifiers as well as the built in RF switching cos if you want to run data or even CW you want better control of the Amp than RF sensing. Has an RCA jack for the PTT on rear so easy to connect to. kl505v Bottomkl505v back

Don’t forget that are not allowed to use the KL505V on CB. OK? I hope you understand and won’t do it. Triple nickle is OK cos not CB. The Amp does not have any fancy stuff built in to prevent you using it on CB so you have to be disciplined and not do it because it will work very well there I am sure.
You do need to be a little bit careful when you use the KL505V.
Don’t over drive it. !!!!!!
Keep the output under 250w PEP. The manual says 1-10w input on AM/FM/SSB and CW for 300w output. I think 10w input is fine for SSB but I wouldn’t go over 5 or 6 watts carrier on AM/FM and CW.
The manual also says the current draw is 34A max at 12-14 volts DC. There are 3 fuses inside the amplifier. Blow the fuses and your warranty is void because you will rip the warranty sticker to open the case to replace them! I should have checked the fuse value when I had the case open. 12A a piece would make sense. kl505v boardKL505v Finals

The KL505 is a hardy little beast but we just don’t know how good the transistors are inside it. (Cos we don’t really know what they are!)
10 to 12w PEP on SSB will usually see around 250w PEP  out (on the higher bands) and trust me..that’s fine..that’s good..that’s enough. The fans work well and keep it cool. I am sure it will go harder but without any filtering you don’t want to be pushing this too hard or you might just get an award for the Worked all neighbors awards, with credits in toasters, electric organs and stereos! You may not notice it but the audio is starting to compress. I hear stories of people saying they are feeding it with 30w and seeing 375 to 400 out. I am not saying they are full of shit but you will soon need to repair your amp. It is not designed to be used like this.

The KL505V has a 6 position power switch. Low to High. It is not a power switch. It is an attenuator. A portion of your input power is being feed through some resistors to reduce the input power. If possible, reduce the power of your radio to less than 12 watts and run the amp at level 6 with minimal attenuation. Otherwise you are wasting power.
Its got a preamp which I never use cos all it does for me is raise the noise and reduce the intelligibility of the received signal, but there may be cases in a really quiet location and a really bad antenna it may do some good, but I have yet to experience it. The amplifier is just too broad banded for anything like this to be of any use. Leave it off. If I could order them without the preamp; I would.

Because it is simple and without protection it will work in situations where other similar amplifiers (like my Tokyo Hi Power with all the bells and whistles) will shut down due to CMC on the feedline, or RF floating about, or god knows what. And that is why I like it! You just have to be careful, Watch the input, if your antenna is a bit dodgy and the SWR is a bit out of whack; knock the power back and it will keep working. Use it wisely and it will serve you well. Run it flat out for too long and you will probably be looking for 4 new output transistors.

I know of quite a few Hams who are running this amp after their radios with 10w PEP so they don’t have to run their Icom’s flat out. Cheaper to replace the finals in the KL505 than their Icoms they reckoned! They also got 200 + watts out! And… they have been known to forget and run 100w into it and “poof” no more amp! Replacement with a matched set of SD1446/MRF455  and away it went again. Happy camper!

The Finals. They say “SD1446” but they really don’t look like Toshiba’s to me cos they also have RM Italy stamped on them. RM is getting them from somewhere and re-stamping them. Unless They have a special agreement with Toshiba to stamp them? Nope..Mike just told me that Toshiba stopped making them 15 years ago. RM say they are getting these finals made for them. I guess they are using them in all their larger 12 volt HF amps. All the more reason to take things easy with the KL505V. In the accompanying KL505 circuit diagram the final transistors have the numbers blacked out so no information there.  Like all RM Italy stuff the board is well made and neatly laid out. Rev 6.0. I don’t have an original KL500 to compare it to but the KL505V seems a bit beefier with longer fins on the heat sink. And it is black. Stealth.KL505V on box

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Portable “Antenna’s”

Since I got the Xiegu G90 I have been playing around with building suitable antennae for other bands such as 20 and 40m. I was pleased with the results of the coax end fed antenna I build for 10 and 11 so knocked up something similar for 20m. Initially I tried just putting a choke round a ferrite core at the 1/2 wave mark but the analyzer was showing things were way out of whack so removed it and wound an electrical quarter wave of coax around an 8″ plastic core.  Instantly showed an SWR low around 13.5mhz and 3 or 4 goes of removing a couple of inches of coax from the top of the coil had an SWR of 1.17 at 14.2mhz. But I had a problem. My 10m pole was not really long enough to keep the coil off the ground! It was difficult to set this antenna up vertically due to the length. At this point I decided it would not work for me and went to work on the 40m dipole. This was also long but a few times of fold the wire back on itself, test, if OK snip off the tail, test again, fold back, test, snip, test…etc etc soon had an SWR of 1.3 : 1  at 7150. Feed point up about 9.5m and ends at 3m off the ground. Easily covered the entire 40m band under 2:1. I am sure if I was to raise the antenna further; and efficiencies improved the SWR curve would be much sharper. For the amount of wire and work to get a resonant 40m antenna in the air this has to be the easiest yet. The wire was plastic coated and quite light but for portable use it should be OK. Not something you want to put up as a “set and forget” antenna by any means. No balun. Just direct feed to coax. Portable. 20w max. Just needs to work. I think I will make something similar for 20m. Simple is always good when out in the woods. And Inverted V’s do work well and they don’t have to be heavy.  For a single pole set up I think an inverted V is the simplest, cheapest and possibly most efficient antenna one can make for portable use. It is resonant on one band and that should be the band you are working on.

Join the 40m wires together and could be forced into use on 20m as a quad!

When it stops raining I will be going portable on 40m.

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XIEGU G90 SDR

xiegu front panel

This little radio is causing a few waves around the world and it is not hard to see why. It is the complete portable set we have all been waiting for and it does work rather well. It has all you need to head off into the hills with a piece of wire and a battery and get on the air. It receives well and the 20w PEP output on SSB will get you heard.

There is a lot going on with this radio but it doesn’t take long to sort out the things that are useful. Changing the frequency, mode and band are all off buttons either on the front of the radio or on top. The buttons are small and don’t convey a lot of feeling. I have read a lot of complaints about the buttons not working well. In my experience you must not press the buttons too long Just a press and back off. Hold them too long and they do nothing. They are not back lit or easy to read so best try to remember where they are!

What don’t I like about it? Not a lot and they are mainly minor. Its a tad heavier than it could be. The DC line seems a little flimsy and the buttons take some getting used to. But once you do get this thing on air it plain works.

I was hunting about for the DNR but it doesn’t seem to have any. Didn’t stop the signals coming in. Filters could be narrowed but the passband doesn’t shift. The mic compressor did not seem to work. Big deal. No RF gain control, just an attenuator and a preamp. It didn’t stop the radio from doing the job it was intended to do which was to transmit and receive signals.

The Tuner works on just about everything. Power is adjustable from 1 to 20 w in 1 watt increments. The fact it puts out 20w carrier in AM and 20w on SSB would indicate it is not being stressed on Sideband. It receives very well. Signals just pop out of the noise. The display shows a lot of whats going on and Ver 1.7 of the firmware also decodes CW. This radio came with Ver 1.6 of the firmware and I have not got around to updating it. too busy having fun!

The head is removable. The connecting cable is in the box along with the cable to update the firmware. I really can’t see me remoting the head because the cable sticks out the back and would make it difficult to stick on to a dash board or whatever. Someone is going to have to come up with a bracket to hold the head securely somewhere using the screw holes on the head that secure it to the body. It also needs a bail to hold the radio at a better viewing angle when in use. The speaker is on top but I think most people would want to use headphones in the field. A lot of the functions are also available on the microphone if your fingers don’t suit the buttons on the radio. Mic cable is a straight ethernet RJ45 cable. I am hunting around for a flat cable to replace the stock to reduce the flexing of the RJ45 socket on the set. There are also RJ45 right angle adapters that would work well to keep the mic cord from sticking out at 90 degrees.xiegu mic

I am not going to go into how to do this or that, but I do feel the majority of users will find this radio to be very friendly to use and it works surprisingly well. I don’t know what improvements the makers will make via software updates but it will certainly be interesting to see what the future will bring.

The mod to get it to TX from 0.5 to 30mhz is out on the net. Didn’t take too long. Hopefully Xiegu will not counteract it in software in later updates.

Bottom line is that this is a great little radio which will continue to get better with every update. It can only get better!

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Programming 10m ‘CB’ Radios

What an oxymoron this title is! You can’t have a 10m CB radio! Either it is a Ham radio or CB radio. Supposedly. What I mean by this is a radio that covers the 10m band but retains it’s origins as a CB radio by doing it it bands of 40 channels. ie most export CB’s. Except the Optima and maybe a few of the earlier sets which are no longer produced. The fact that almost all of the ‘export’ radios we can buy these days are programmed in bands of 40 channels really pisses me off. Why not 100 channels? Why 10khz steps. None of them step in 5khzs, (except the Optima). But the Anytone SSB 10m radios, and the maxlogs  allow us to define what is actually in the bands themselves. That opens up a few opportunities.

Like what?
Well..lets take the AT-6666 as an example. Out of the box it covers 10m only. Plug in the programming cable and run the program on your connected PC and we can opt for the full coverage mode of 25.6-30mhz, spread over a bunch of 40 channel bands. The program also gives us the ability to decide what frequencies we want to have in those bands. For example; many New Zealanders still want to have access to the old 26mhz CB band. No problem, just go ahead and input 26.330 into Channel 1 of band A and keep on going till you have all the 40 channels written up then upload it to the radio. Turn it on and you have the NZ 40 in band one ready to go. Awesome..and 60 watts of PEP to drive it with. The AT-6666 should be available ex stock NZ in a couple of weeks for around US$250.

Lets face it..the 2 bands in 25mhz are useless (anybody use 25mhz?)  so I would put NZ 40 in band A and the US 40 channels in Band B. That brings us to the wonderful freeband, that area between 27.410 and about 27.855. Bands C and D get entered with every frequency from 27410 on up with 5khz steps. Forget about the channels up here as they are pretty meaningless anyway. look at the frequency on the radio. Alpha channels in order!
Band E. Input the CB Marine frequencies and any other specialized frequencies you may have.
Band F,G,H,I and J. Start at the beginning of the 10 meter band and input the entire band in 5khz steps and whatever of the 10m FM segment suits you. But the AT 6666 radios can’t do split. There was one radio I remember having to input TX and RX frequencies into. Forget which one. All these radios will step in 1khz steps if set to do so but default to 10khz or what has been programmed in the band.

The Lincoln 2+ does do Split TX and RX but we can’t input frequencies for the individual bands. (Yet.) The lincoln 2 is an Anytone design and I suspect build. Its made in China. The Mckinley’s and Grant 2 are made in Vietnam and to my knowledge we have no means to mess with the Grant 2 and Mckinley with a PC and programming.  I doubt if that will change.

So if you want to get your NZ frequencies and increased power with a new SSB CB radio you better get an Anytone.

NZDAT

The Anytone AT-6666 and the lincoln 2 and the Stryker 955 seem to share a common architecture despite looking totally different outside.

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President Grant Expanded Mode

president Grant 2 Premium

Once the Grant 2 Premium is Expanded several functions are added to the radio which are not covered in the Manual. Despite an upgraded mother board there has not been much change in the way the radio works, but here is what I have found so far.

  1. The frequency coverage is increased from 25.615 to just over 30mhz in 10 bands of 40 channels. To scroll thru the bands repeated press’s of the F button. Bands are identified on the screen from A thru J.
    A is the normal 40 channels and B is the freeband. A bit clunky. As you change the band the last frequency you were on in that band will be displayed.
    If you are going to be doing a lot of navigating with this radio I recommend using the memories, the programming of which is in the manual so I won’t cover it here.
  2. The Power is increased to around 20w SSB/FM and 8 AM depending on tune.
  3. Up 10kc.  To access the Alpha channels a long press of the Mic Gain button jumps the frequency up 10khz and the ‘mhz’ wording on bottom right of display will blink repeatedly. Another long press reverts back to standard. The frequency will change accordingly but no change to the channel numbers.
  4. Minus 5 Khz A long press of the MEM button will drop 5khz and the frequency will track the change. No other notification so keep your eyes on the frequency display! Both the changes in 2 and 3 remain in effect until disabled by pressing the appropriate button again. Turning off the radio does not cancel the function.
  5. UK CB Channels. The UK CB channels can be accessed from the mode button. keep pressing the mode button from AM to FM to USB to LSB and the next press gets you into the UK FM CB Channels. Cool if you live in the UK I guess. President Grant 2 PPresident 2 prem UK

The Grant 2 Premium is still a CB, but a glorified CB. Great little CB actually. I think you might find it a little restrictive to work in the 10m band as you can only work frequencies ending in 5 and 0. It has 5 memories which can ease the navigating niggles of 10 presses of the F button. I prefer the green to the orange display colour but everyone is different. Not much not to like. The extra power and heatsink are worthwhile additions.

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