My interests and activities 

40 years of Motorcycling 

Over 40 years on two wheelsl. I worked out that over 40 years I owned over 40 bikes in. Its a shame some of older photographs didn't survive the years but I do have a few of my newer bike and a few from the 1980s. 
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Noisy HF Bands what can we do about it?

​​Number 1 = Stop using your transmitting antenna for receiving on.
​Number 2  = Get a dedicated receiving antenna.                                    

 Antennas for 160 - 80 meters

         Noisy HF Bands 

Receiving Antennas

I purchased a mini whip from the usual on line auction site form a Russian radio amateur RA0SMS. I couldn’t buy the parts and make this in the UK for the price he was advertising. So I decide to give it ago and made a purchase. 2 weeks delivery was very quick and the postage was included in the price. This is now 45 feet up on the mast at the end of the garden to keep it away from any noise source. 80 meters and up it is brilliant for such a small antenna, but the 160 meter band is spoilt by the local AM stations. They appeared to spoil the reception all the way up the band.
To combat the ever increasing noise level on 160 meters I replaced my old 160-meter coax receiving loop with a Wellbrook ALA100LN large aperture loop. These are not cheap in my opinion, but I had to try something to reduce my noise on the 160meter band and this looked like the best option for my location, plus it gives you a bigger scope of experimentation with the option of using the amplifier on different size loops.

I was very impressed with the build quality of the loop amplifier and the power interface; both these were very nicely finished in cream coloured weatherproof boxes.
After reading more information about the loop and the amplifier I was worried about overloading the loop amplifier with RF from my doublet.

I had a chat with Andrew at Wellbrook about of my concerns regarding RF damage to the amplifier and the positioning of the loop under my 260-foot doublet which would place the loop in a very high RF area.
Andrew said I could make the loop any size from 6 to 18 meters in circumference and he recommended I try an 8-meter loop first. This would reduce the amount of RF the loop amplifier would be subjected to.

After further research I decided to make two loops on the same frame, I made the frame from 2 glass fishing poles and I used a cheap rotator to do the rotating bit. Although you only need 90 degrees of rotation and after using the loop for several weeks I don’t rotate it very often so maybe you could do without the rotator.

I made the outer loop 8 meters in circumference and then included an inner loop 4 meters in circumference. The loops are switched from the shack via a relay arrangement mounted in a plastic box between the 2 loops. I can now select 8mtr or 4mtr loop from the shack.

The good bit about making the loop smaller was the space required to rotate the loop meant it would still fit within my layout in the garden but as I said. Do I really need to rotate the loop?
At my QTH I do suffer from a strong local AM broadcast station about 6 miles away. This has caused some issues in the past, but I was keen to see how the Wellbrook coped with this strong AM station.

I connected my radios to the loop, Icom7300 and my FT2000 and neither of them suffered from overloading from the AM stations on the 160-meter band but when I connected my SDR play receiver to the loop it was a different story. It has always my plan to use a separate receiver for the 160 meter band using some sort of receive loop, the SDR play was receiving AM broadcast stations all the way up the bands. I connected my doublet to the SDR play and I didn’t have a problem so it looks like I will have to build a high pass filter to eliminate these AM stations when using the loop on the SDR receiver. Click the link for more info about the SDR play and the new RSP2. Tests so far have been very good and I am impressed with the wide band coverage which means I don't have to retune when listening around the bands. Switching between the 2 loops does make a difference and obviously a reduction in received signal strength but well worth doing.
More to come after some testing.

​Well... The Wellbrook finaly died as expected. not really worth the money. Impossible to repair.
Todays antennas. My antennas are always changing but today when I wrote this I only had 3 antennas. 
I have a  80 mtr inverted V dipole@ 50ft  a 40 mtr inverted V dipole dipole @ 50ft. And for 160 mtrs I have my inverted L.

For receive o 160 mtrs I purchased the Wellbrook Loop.
The Wellbrook loop stopped working a while ago and my home made version of the welbrook is still working OK, Oviously somthing has blown the amp in the wellbrook even though I take every precaution to protect it.

My final summary of the Wellbrook... too expencive and doesn't last long if subjected to strong RF feilds. £180 for 10 months makes this the most expecive anntena I have purchased and now its a paper weight.
​Better anntenas are out there at a fraction of the cost.

The main bands I am interested in are 160 meters 80 meters  and somtimes 40 meters.
I make all my wire antennas and feeders and a few are featured on here.

Mini Whip

Wellbrook ALA100LN

Scott had this mini whip on test for a while at his QTH, Scott Unfortunately also lives in very proximity to a large AM broadcast mast, about a mile away so his problems are much worse than mine.

Scott installed additional filters into the mini whip to narrow down band width. This was to make the mini whip a 160mtr band only. The installed filters cut off signals above 2MHz.

160mtrs is our main band of operation so at this point in time this was all we wanted. A high pass filter was added to the receiver antenna socket and this did suppress the AM signals considerably reducing or removing images from 1332khz transmitter.
The conclusion so far is the Wellbrook loop is outperforming the mini whip on signal to noise. I can receive a signal at S9 with an S2 noise floor, so weak signals now stand a chance. The received signal from the same operator was S9 on my inverted L but with a noise floor of S7 to S9. The Westbrook loop wins the top band antenna choice.
Something seriously worth considering if you are installing a receiving antenna

Front End Receiver Protection

Produced by Peter OK1RP

Click the picture to visit his web site.

Original design by
 Gary, KD9SV

when you have put up a receive loop or mini whip or any other receive only antenna for that matter you want to make sure you don't transmit RF into your receive antenna and then into your radio causing expensive radio damage. This is a serious thing to consider with receive antennas. To avoid this problem some form of switching is required to stop RF getting into your radio or receiver.
A good protection circuit to eliminate the possibility of blowing out Your receiver's front-end while using these auxiliary receive antennas specially on low bands.

I was discussing this RF problem with a local Radio amateur G8EQY who has facilities to hand to produce the cicuit board for this project. The following week Scott gave me the finished and built circuit board ready for testing. Totaly unexpected and an amazing quality job. See the pictures of Scotts completed project. The relays used are HJR1-2C L-12V DC which have an  operate/release time: 6/4ms and these work very well.
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OK so what does it do? In simple terms it disables your receiver antenna before switching your transmitter to TX. Connect your foot switch or TX button to the box/panel then connect your transmitter PTT line to the box. The coax through the box is cutting off your receive antenna before your transmitter goes into transmit. I use this to protect my SDR Play and FT2000D. The FT2000D & TS2000 have a receive antenna sockets. All my transmitters are connected through the box and one PTT button is in use.
You could always use a light bulb Hi Hi.
Home brew Loop preamp installed in spare plastic box I had just so I could try it out. The results are very good and it is camparable with the the wellbrook loop. Still doing back to back tests but it looks like its going to be a very good performer. After the recent loss of the Wellbrook loop this has become my main 160 mtr reeiving antenna and its working very well.
Landing at Leven Airfield.Filmed by Phil M0VEY
Day out to the Hornsea Rally. Departed Peterborough Conington Airfield landed at Leven Airfield north of Hull. Picked up by Phil, Rog and Nick. 
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