Friday, December 5, 2014

Hello and welcome to  Xtract 031 of the HX Files.
In this issue of Echo Ireland I would like to talk about some of the aerials used /portable (and at QTHR) and the means to fix them in place when out /p.

In photo 1 above, you can see some aerials mounted on a small portable mast that has been used many times, all the aerials on it are for 23cms (1.2ghz) the top one is a vertical and the others are various types of beam aerials such as what would be classed as a regular type of beam, the others are a loop Yagi, and a circular polarization type. In use there would be some coaxial cable used to connect the transceiver to the aerial but on some occasions the transceiver is screwed direct to the aerial and a remote lead carrying the power, audio, video and TX/RX switching from the car to the mast mounted transceiver.

Photo 2 above shows one of the stands used, it works on the fact that you drive over the base of the stand and the weight of the car holds it in place and it does not need any stays to hold it in place. This base unit was the mk1 type; it was made when I had a 5 door sierra, and made as a fixed item. It became awkward to transport in the boot model car I got next and the base unit was left aside for a few years. The latest car is a hatchback and is well able for it, but not long after using the base for a few times I got someone to modify it, firstly he had to separate part of the base frame and make it wider by inserting  an extra piece of box metal so some hinges could be wielded in place, also the rigid support arm on its right side was cut away and its ends modified so that each end was held in place to the base by a bolt and when one of them was removed the unit could be folded flat for transporting and storage, the base can be seen again in photo 3 below along with some of the mast bases  that were bought  / made over  the years. 

 In photo 3 above you can see the various ways the aerials are used /portable whether attached to the car or being held upright by other stands. Some of the masts would take a couple of people to erect safely, but others could be attached to the towing eyes or the tow bar. You should take care when you are on your own working /portable, you could end up with some damaged aerials, or car as the pole with the aerials attached could be to long and will be top heavy for you to manage the assembling of the aerials and mast, and their dismantling, the dismantling part can be the most dangerous regardless of the weather, as fatigue could set in after a long day and with possibly cold / wet hands  you could lose your grip and have to repair a boom and a few elements on an aerial or two, and remember if you are on a height you do not need a skyscraper of a mast, if you are on your own just bring something you can safely manage by yourself.

 In photo 4 above you can see some of the other aerials that did not make it onto the mast, these bow tie aerials can be used individually or some of them could be placed into the panel aerial case you see them resting on. (The panel aerial is for use between 195-197 MHZ.) When it comes to connecting your aerials to your transmitter other than coaxial cable, the range of fittings can be bewildering as can be seen in photo 5 below.

Photo 6 above shows a dish and on the bottom right of it is an aerial that looks like a can, and it could be used as is for some local use, or it can be used as a launcher and lined up to feed a dish like the one it is sitting on, but some framing, and exact measurements would have to be done to attach the can to the dish at the right distance but that is a job for another day.
That’s it for this issue of Echo Ireland and indeed for this year.
I would like to wish you all a Happy Christmas and a Prosperous New Year.
And that all your signals are P5.

Thursday, December 4, 2014

 Hello and welcome to 030 of the HX files.
In this issue I would like to talk about some of the “few” parts bought at the Friedrichshafen Rally in June.
In photo 1 bellow,

you can see some of the leads and parts purchased, in the picture you maybe able to make out a couple of small monitors, various leads, fittings, and a couple of RF amplifiers.  Not in the photograph are a couple of transmitters, receivers, and a couple of aerials that were bought for some future projects. Some of the leads and fittings will be used to replace the ones taken out of other units not being used at the time, and the rest for stock. It may look like a lot, but when you take in to account the parts and modules used in a project, such as the transmitter, receiver, amplifier, preamp, relays, coaxial leads and aerial to be used, and the fact they all have to be joined together, it is a wonder any RF gets out at all, and you would be left wondering
where did all the leads that were bought go to.

On the subject of fittings and RF, in photo 2 above, you can see some fittings, some of the connectors go as high as 24ghz, they are not exactly falling out of my hand and this lot had not a lot of change out of €120. As with any radio rally those of you who have attended rallies over the years would get to know the various sellers selling equipment and also other traders and buyers who have dealt with them. The fact that some of them have been in the business of designing and manufacturing for years, and take pride in showing their equipment is 100%, they would have the spec sheets of their products for you to inspect, some even go to the bother of bringing some test equipment to show the buyer the equipment running before you buy, even more important some of the traders would let you know the ones that whose claims of their equipment would not live up to what is stated on the label.
 Prices can vary quite a bit as some items can have less of a demand in one country than another, and as a result you could buy well from one trader and in the next row of stalls see the same quality of gear from someone else a lot dearer/cheaper than the last trader, so when you have bought your parts for a steal, stop looking for them at other stalls to see how well you done as you will feel like you were robbed if you see them cheaper. The cheaper parts may just be that, cheaper, or be a cheap brand that may not be up to the spec you need and all that lovely RF will go any where but to the aerial.

 In photos 3 and 4 above, you can see a couple of the amplifiers bought at the rally, one is for 5.7GHz and the other is for 10GHZ .
Below in photo 5 shows some more fittings.

The worst part of this rally is not having my own car with me, and seeing plenty that would fit nicely in the boot, not only the various new pieces of equipment, but the “scrap parts”. One piece of equipment bought was a repeater that could be modified for 10 GHz, these pieces of equipment weighed a few kilos more than my total allowance on the aeroplane, I would have loved to have brought a couple of the units home with me, not only was the enclosure a nice size but was meant as a mast mounted unit and was waterproofed and it only had the wave guide connector and a small multi plug for the dc connections. Inside the unit, other than the TX/RX equipment, there where some lovely fittings and brackets to be had, but as this item was purchased on our last day at the rally we knew that the limits of our allowance was getting close and something had to be left behind, as the extra charge would have cost 5 times the amount paid for them, so knowing some of the traders I got a loan of some tools and the parts wanted removed, and in these recycling times, the metal container and other parts where given back to the trader to sell to someone else, he was so happy to take them back he said that we could have some of his other stock, as the container was a seller on its own and it saved him the grief to disassemble it. As you know quality cost but I wished it didn't cost that much, cheaper fittings and connectors could have being bought but they would have being no good at the frequencies I wanted them for, and as mentioned earlier the need to get as much of the RF out of the equipment as possible and into the aerial, as one of the high power transmitters(or should that be QRPP) bought can push out nearly 100mw and so some high end connections (and a amplifier) will be used on this project that would be a permanent outdoor unit, now where can I get a professional waterproof enclosure to house everything and keep it dry and safe, (ah feck).  
That’s it for this issue of Echo Ireland.
May your signals be P5.


The HX Files 029

Hello and welcome to Xtract 029 of the HX files.
In this issue of the HX files I would like to take a brake from the construction of a couple of items I have currently on the work bench. A couple of parts are needed to complete both of them and I am hoping to get those parts needed at the rally in Germany in June. Not wanting to remove any parts from other projects (like I have done before) as these parts would mean a total dismantling of the projects and this time that was not on.
And now, time for something completely different.
 So in this issue of Echo Ireland I would like to write about some of my eclectic mix of “collectables”. Some of these items were bought because of their “rarity” and some because they are just plain weird; I will leave it up to you to decide which is which.
The first items are a couple of ceramic insulators from (I am told) an aeroplane, these would be placed either end of the plane and the aircraft wire aerial would pass through it. In photo 1 bellow,you can see that each has a couple of aluminium rings that attach it to the craft from both sides of the aircraft's skin.

Number 17 set

 In photo 2 above, you can see one of the radios in the collection, it is a Second World War radio called a “wireless set number 17”, there were two versions manufactured, the one I have is the MK2, the MK2’s operating frequency is from 44 MHz to 61 MHz. Some info for you power hungry hams out there, it could produce around 300 watts, nah only joking, actually its power output is more like +/- 250 MW, and with either one of its complement of aerials a distance of some 10 plus miles could be “guaranteed” and that was more than enough as you did not want the wrong people ear wigging. Its main use was to communicate from the ground support units of Barrage balloons and Anti-Aircraft locations to HQ, and it replaced signalling lamps( that would be used in the daylight as well as the night, and you did not want the enemy pilots seeing the beam of the lamp at night). As there was a war on, and metal was used for other things, the radio’s cabinet was not made from metal but from wood, the manufacture used as much wood as they could in its construction, I wonder if they tried to make the valves from wood and found that they wooden work. Some details for those of you with no grey hair, it was a ready to go rig and was powered by two 60v dry batteries in series and a 2v 16 ah accumulator. The No 17 used two valves, one each of an AR6 and AR18 type valve. It was mentioned in a radio conversion book that told you how to modify some of the ex-military radios that were available to the radio amateurs, that you should leave the “No 17” set alone, as it would cause interference to other radios close by even when it was in the receive position. The weight of the radio is around 10kg, and its measurements (in inches are), 14½ W,16 H, and 10 D,  it was made on a budget and when the bombs were dropping you did not want to be carrying a big radio as you would used your hands to keep your hat and trousers on whilst running for shelter. As mentioned earlier, before the “No 17 set” there was the signalling lamp like the one in photo 3 below.

 The case contains the lamp, which had a removable red filter for daytime use, also in the case was a stand made from some small lengths of tubing that would screw together and then be stuck into the ground. Also in the other compartment of the case would be the battery, and a spares kit including a spare bulb.  No space was wasted, as the Morse key is mounted on the inside of one lid and the instructions for its care and use on the other, also the lamp itself has a couple of features, one is at the bottom, it is a small screw that when loosened the lamb could then be easily tilted and lined up to the senders target, and on the lamps top is a sighting tube. Not a telescopic sight but simply a tube with a round hole at the sender/receivers end and a plus (+) shaped hole at the target end , you might be able to make it out in the photo. In photo 4 below,

 you can see some microphones, the bottom left one is a WW2 era throat microphone, it was used in noisy environments like airplanes, top left is also a microphone and not a ray gun from Flash Gordon, top right is a head set from a Marconi marine base radio I think it is was called a triple diversity transceiver, and the microphone on the bottom right is from another Army radio.
And finally
That is it for this issue of Echo Ireland; in a forth coming newsletter I must mention some of the other military radios and Morse code keys and other bits and pieces in the collection. Perhaps you could send in an article yourself about some of your own collections of the weird and wonderful.