The EUropean AMateur SATellite reflector

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The Eu AmSat Forum has recently migrated to a new web address. The forum is well worth a visit and will be particularly interesting if you are a satellite fan or operator!

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Do You know What The Word HAM Means?

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The word HAM is often used by many as a shortcut for amateur radio “ HAM RADIO ”. As a radio operators we call ourselves “ HAM ” or “ HAMS ”. The actual meaning of HAM is taken from the three pioneers that helped to make it possible for us all to become “ HAMS ”. The letter H stands for Hertz ( Heinrich Hertz ) who helped to develop the theory of electromagnetic waves . The letter A stands for Armstrong ( Edwin Howard Armstrong ) who was successful in inventing FM ( Frequency Modulation ). The letter M as you may have guessed already stands for Marconi ( Gugliemo Marconi ) who was the first to transmit signals across the Atlantic. H = HERTZ A = Armstrong M = Marconi
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Full Size Delta Loop for 20M

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I came across a simple delta loop design courtesy of dxzone found on the net some time ago and have been planning to give it a go for a while. This weekend I had a couple of hours spare, so I decided to give it a go using some 2mm multi strand wire cable, a dipole centre and a mixture of 75 ohm and 50 ohm coaxial cable. The delta loop is supposed to be resonant on 20 meters but I found it to be a little high so at present I am tuning the Loop with my mfj-969 which copes extremely well. The resonant frequency is 13.2 MHz at the moment so the next chance I get, I shall shorten the overall length making sure that each of the three sides are still equal in length, and hopefully adjusting the antenna for maximum performance ATU free for 14.2 MHz. I believe the miscalculation in the resonant length is probably down to the fact that my wire is covered in the plastic sleeving from the manufacturer which always effects the swr as I have noticed in past experiments with dipoles you always get sl...
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Homebrew 40/80 Trap Dipole Design

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This Antenna design was one that I used about 4 years ago, it worked exceptionally well on 80m and 40m. The size of the antenna makes a Half wave length on 80 meters, and with the traps a half wave on 40m with a SWR (standing wave ratio) of 1:1-1.5 across both bands. It worked well also on 20m with the use of an A.T.U (antenna tuning unit). I made my version of this antenna using 3mm multi strand copper cable which I left covered by the PVC insulation. The traps can either be home brewed using some 40mm diameter plastic drain pipe and winding wire around the pipe approximately 10 turns, then connected in line after the 10 metre lengths. Or the alternative is to purchase some commercially made 7.1 MHz traps, and fit them in line the same way. The antenna can be fed with 50 ohm coax with a home brew balan or again a commercially purchased balan. The wire lengths of the dipole are 2x 10 metres and 2x 6.7 metres as shown on the diagram above. This antenna can be mounted quite low to the gr...
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YAESU FT-857 Front Panel Repair

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Over the past 12 months the display on my Yaesu FT-857 has developed the "zebra stripes" problem which after looking in to it, this has probably happened because of high temperature from the sunlight entering into my vehicle. The best way to resolve the fault is to install a new board into the front panel which I carried out last night with successful results. I began by contacting YAESU UK who came straight back with the cost and part numbers which was very reasonable as the total cost for a complete brand new panel and new AF/SQ VR control was under £140. The panel has a screen and selector control so I thought I would renew the AF/SQ control at the same time. The staff at YAESU UK are extremely knowledgeable and very helpful indeed, I gained a few tips from one of the gentleman at YAESU UK regarding the task I was about to undergo.  The AF/SQ VR required careful soldering as the terminals are very tiny but apart from that the job was not too difficult and I managed t...
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Home Brew 80m Delta Loop

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click to enlarge image of Delta Loop I have been so pleased with the 20M Delta loop I decided to scrap the dipole and have a go at home brewing an 80m Delta loop instead. The result was well worth it as I found that the new loop antenna receives and transmits very well on 80M (resonant band), it also tunes up very easily on 160M & 40M, giving impressive results with very low noise levels. The Delta loop is installed as seen in the above image with all of the dimensions included. I shall be posting more once I have had chance to test it further, I am really pleased so far and excited as usual, I'm looking forward to telling you more!
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YAESU G - 5500 Elevation Rotator Repair

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After 10 years of careful use my G-5500 eventually developed a couple of faults on the elevation rotator side.  Fault 1. For the past year I have had to guess the elevation as the readout was no longer working on the controller unit. I suspected the position switch which was located inside the rotator up above the house roof which was a pain in the butt to say the least. Fault 2. Over the winter the gearbox on the elevation rotor seized up solid. I plucked up some courage and erected my ladder and which with the aid of a rope to lower the mast it all worked out quite straight forward. Once down out with the impact driver and away I went. Once I split the case with the impact driver which was easy, I found lots of sandy grit and dried out remains of what should have or once was gearbox/bearing grease. The next step was to inspect the seized gearbox and then remove the main shaft which can only be carried out by first removing the entire gear housing u...
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New DX Contact 0n 12 Meters

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Today I managed a nice QSO with Tom ZD7X who is located at St. Helena which is quite a distance away from my location. I managed to work Tom ZD7X with a 5/9 report operating my FT-767GX with my home brew 20m delta loop assisted with the MFJ-969 to tune the antenna with 50 watts on 12 meters. 12M is rarely open and I have only had a few QSOs on this band so I guess the new Cycle has begun at last! Good DX de 2E0HTS 73
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Yaesu FT-890 Frequency Drift

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FT-890 & Recent Delta Loop Experiment: I have owned my Yaesu FT-890 since 2002 and have enjoyed years of reliable service. A couple of months ago you may recall that I recently reinstated the FT-890 as a second set up allowing operation from our dining room as well as my regular shack. I have since worked a good page and a half of paper logged QSO's into places like the Middle East, The US and EU as well as across Russia. I have been using the homemade 20m Delta Loop that I recently made and installed which is performing very well on 20m. The delta loop works well on 17m, 15m, 12m and 10m with the help of an old Nevada TM1000 manual antenna tuning unit.This week I managed to get into a couple of US repeaters up on 29Mhz using the FT-890 and Delta Loop which is pretty cool. Frequency Drift:  Whilst enjoying my old rig I discovered that it had developed an error and occasionally would drift up and down frequency both RXing and TXing. The drifting in frequency seeme...
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20M Corner Fed Vertical Delta Loop

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I hope you all are having a wonderful festive time, among the festivities I got an hours fresh air outside earlier when I fixed myself up with a very nice additional antenna. Its coming up to about a month since I installed my old YAESU FT-890 neatly in the corner of our dinning/craft hobby room. I had strung up a 20 meter dipole at first and made a few qso's into Europe but noticed I was picking up some noise which spoiled the reception quality.  I changed antenna's from the dipole to a delta loop to compare and as expected the delta loop was much better with hardly any noise. I tested the loop for about a week until the YL noticed a corner tied off to the washing line pole which resulted in the "look" which translates to "move it now". So today I got my weights and rope along with the delta loop and began throwing a weighted rope up into a big tree which is part of a wooded area at the bottom of my garden. The land after my wall is a steep banking tha...
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YAESU FT-470 Battery Modification

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I have owned my trusty FT-470 for over 6 years and have worked many DX with it whilst working through the FM Satellites. I’ve used it whilst out and about Mobile as well as lots simplex and repeater use for years with excellent receiving capabilities compared to the more modern Hand held’s. I have been running with AA, NiMH 2.300mAh 1.2V Rechargeable battery’s housed in a Yaesu FBA-10 Battery case, which still works very well with hours of quality operating time. About a year ago I managed to acquire a second FT-470 from a local rally for a bargained down price. The latest FT-470 came with an original FNB-10 - 7.2v 600mAh Ni-Cd Battery pack that held its charge for about 15 minutes whilst receiving and a lot shorter when transmitting. To get around the faded FNB-10, I have been using the latest FT-470 with the PA-6, Dc Car Adapter/Charger, fed with a 12v Motor Cycle Battery and the original FT-470 on the FNB-10 Ni-Cd pack whilst hooked up to the Arrow Sat antenna. I like the performan...
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