Saturday 27 August 2016

GB0SA - Selby Abbey CHOTA - 10th September

Ofcom have issued me with GB0SA for this years Churches on the Air day station on the 10th of September from Selby Abbey,

We hope to be set up with a 40m dipole raised on three masts, and on air by 09:00 local time on the saturday morning. The station, using modern mobile HF equipment, is likely to be located to the right of the main entrance, with the PRC-320 held in reserve.

Wire wrapped

A few days ago, I took my boys to play in the local woods, and my PRC-320 as well so I could have a play. Sat on the top of the hill watching my boys playing, I threw out the 5m wire as a counterpoise, and a quick over a tree branch end fed for 18MHz.

Sadly, on retrieving the antenna wire, it snagged on a split in the branch. Now, rather than my two 'new' antenna wires, I was using a much older one, which had no throwing cord. This meant that I had to throw the actual wire over the branch, and this had snagged on one of the length markers (a big black disk) just a few feet from the end. Unfortunately, in the attempt to free the wire, which was too high up to climb to, the wire snapped.


Im stuck now trying to work out a repair method for this kind of wire! As this is an old roll, Im tempted to remove the length markers and just use it for a random wire when needed. Whats awkward is that the break is at the plug end, i'll need to find a suitable plug that I can attach. I might cut a few meters of this wire off and add a crocodile clip to it to make a ground wire.

After a few recovery attempts, ive decided the 1.2Ah 24v and the 15v batteries are to be dismantled.


Opening the 15v battery is trickier than the 24v, as the top is a thick plastic with a thin rim. Drilling out and punching through the rivets was easy enough, but actually prising off the lid is difficult - ive already broken a small bit of the rim off!



Saturday 13 August 2016

Some More Clansman kit, With great thanks to Mick!

Once thing ive found in amateur radio, and with those of us who love Green Kit or QRP, is that whilst there are a few miserable sods out there (I wont mention names but im sure most people into Clansman could guess at at least one seller...) the vast majority of those ive met are friendly, helpful and generous. The sellers I listed come into this category, as do the members of the G-QRP club,

And now, I an pleased to add Mick, a follower of this blog, to this list!

As a result of Micks generosity, I have now been able to add a thigh strap morse key, the Single Transducer Headset, and the rare (at least ive not seen them often) Boom Mic Single Earpiece Headset, to my collection.



This came about from a request for a metal cased 1Ahr 24v battery to convert. Mick was able to let me have a dead one of these, and also a metal cased PRC-350 15v battery to recell or convert. Another Bergan also came my way, which will be great for taking the 352 up the hills for SOTA, but also gives me a chance to start working on a frame to carry a modern amateur rig and ATU.

So many thanks Mick! It was great to meet you yesterday and chat about all things Green

Clansman Manpacks for Amateur Use - Part 7 - The Epilogue

As a final part of this little series of articles, im simply going to provide an 'essentials' list for each radio - this is the minimum you will need to be able to make use of it. Much of it will be interchangeable of course, so the term 'handset/headset' will be used to indicate that one of the audio anciliaries can be chosen.

PRC-350
Radio
50cm battle whip or 1.2m whip
15v battery or 'C' cell cassette
Handset/Headset

PRC-351
Radio
50cm battle whip or 1.2m whip
24v battery
Handset/Headset

PRC-352
As above, but also
20W amp
coaxial cable interconnect
GSA

PRC-320
Radio
Gooseneck adapter
2.4m whip
24v battery
Handset/Headset
For CW - Morse Key

For the PRC-350 and PRC-351/352 the GSA is advised.
For the PRC-320 a counterpoise, and 5.4m mast (with vertical wire antenna) is advised.
For all, one of the carrying systems is recommended

I would also recommend, if you have more than one audio anciliary, to have at least one standard handset.

I would also further recommend that you join some or all of the various Yahoo user groups, for advice and support. Likewise once you are operational on the ham bands, there is a Clansman User Facebook group, perfect for arranging scheds and announcing your operations.

And thats it from me for this series of articles! Many thanks for reading my mutterings, and I hope that its proved useful and interesting to some of you. Now, naff off and get your Clansman radio on the air!!!

Clansman Manpacks for Amateur Use - Part 6

Ok, we're nearly done! So far in this little series ive talked about which of the Clansman manpack radios are usable for amateur radio, and what you need to make one workable for you, such as the audio anciliaries and the antenna systems. In this second to last article, i'll briefly mention a few items which whilst not essential, will make your life a little easier!

Charging

Probably the very first thing your going to want to do is charge your battery! Now, im not going to profess any great expertise here! Myself, I use a Turnigy Accucel-8 intellegent charger, but thats because it can cope with my Lithium Polymer battery as well as all the others, so is a sensible move for me.

There are a number of standard Clansman chargers, of which the most common is the DCCU. Unfortunately, the 14v version of this is somewhat harder to come by than the 28v version! Whichever you get, you will need to connect it to a suitable DC PSU (which is why the 14v is best for us, as most hams wil have a high current 13.8V PSU!). You will also need a battery charging cable, which plugs in to the DCCU and then into the four pin socket on the battery.

Direct Current Charging Unit (DCCU)
There are adaptor plates and the like also available for the DCCU, but really just the cable is  enough, unless your equiping a small army.

There are some other chargers out there, intended for mains or vehicle use. If you have a bit more money to play with and like to have your batteries looked after a bit better, there is the IBMU (intellegent Battery Management Unit). This will take up considerably more shelf space though!

IBMU
But, what happens when your out in the 'field' and your battery runs low? Well, if your normal you pack up and go home, or put on a spare battery. If your a total masochist, you might fancy spending a few hours turning the knob on one of these

Hand Charger
The hand charger clips on to the PRC-351/352, 319 and 320, between the radio and the battery, and allows the battery to be charged by hand. As nice as it is to have one of these to complete your collection, I really would not recommend trying to seriously charge a battery with one!

As well as the DCCU charger cable, a battery extension cable is also worth having. Originally intended to allow the battery to be kept inside clothing to keep it warm, these make connecting power a bit easier, especially during service and repair. You can of course cut it and add connectors for other batteries or power supplies. They are available for the 24v battery and the 15v battery used on the PRC-350.


Frames, Straps, Bergans

So youve charged your battery and are ready to head off up a hill with your PRC-320 or PRC-352 and play radio. You cant help but have noticed its bloody heavy! What you now need is something to make carrying these sets easier.

The traditional way of carrying the PRC-320 or the 351/352 is via a nice solid, heavy steel frame! The Frame, GS, and the Plate, Adapter, are needed for this (if you get a GS frame, make sure you get the adapter plate and the straps!), which has various captive bolts to screw the radios on to the frame with. The frame also has cable clips for the coaxial patch lead between the PRC-351 and the 20W amp.
GS frame and adapter plate

There is also a 'lightweight' frame available, only its not! (lightweight!) and is considered not as comfortable as the GS. It has one advantage, its design makes standing the radio upright a little easier

'Lightweight' frame
Both are horrible to carry really. But there is a much nicer way to carry your radio - the Bergan. This is a nice DPM (Disruptive Pattern Material, i.e. camo) ripstop nylon carrying pack of the Soldier '95 Pattern clothing series. Internally, there is a long slot to house a whip antenna, and various straps for the different radio configurations (conveniently the straps are marked with which radios they are used with). Externally, the two padded adjustable shoulder straps are complemented by a waist belt, there is a large pocket for ancilieries or a spare battery. There are also various straps and zips that allow additional pouches, commonly known by the Toms as 'rocket packs' to be attached, into which you can cram all the rest of the kit you need.

Radio Bergan (open)
The author, with PRC-320 in radio bergan, and 95 pattern smock
If you have a PRC-350, you will need a pair of carrying straps for this, which are unique to that radio. But, it will also strap into the Bergan.

And thats pretty much it. You now have all thats needed to carry and use these great green radios. Thats not to say there are not other bits of the Clansman range you might like to get, which can make using them a bit easier or more fun. There are audio extension cables out there which are useful, and the CRS/LR box allows the PRC-320 to be used with a remote handset, for example. .

CRS/LR Interface Box


Morse Keys

If your a CW operator, a morse key will be required! The desk keys seem to be harder to come by than the leg keys, which whilst they can be used on the bench, are intended to be strapped to the operators thigh.
Thigh strap key
Bench/Vehicle key
 
I'll try and add a better pic of the leg key later. I myself dont have a vehicle key, but I do have a leg key or three! (the one above, a sealed Racal type, and a beautiful WW2 McMurdo aviation thigh key)


Where To Buy?

Maybe you have been reading this but dont yet have a green radio, and are wondering where to get one?

These days of course, ebay seems to be the main market place. As with anything on ebay, you will find good and bad sellers, and a lot that are mediochre. I will not mention any that I consider bad or just lacklustre, but will advise that you read the feedback of anyone you consider buying from. This is sensible whatever you are buying! Likewise, there are sellers online. Another great way to find them, and accessories, is at ham radio rallies - look for the car boot and junk box sales!

I will mention here a few sellers who ive dealt with and had exceptional experiences with -

LRSeries-Surplus -  On ebay and online. Deals mainly in Landrover spares, but has great deals on Clansman. Dom is a nice chap who ive met in person. http://www.lrseries.com/

PTS Norfolk - Exceptional range of Clansman parts, many small items that you wouldnt think would be available at good prices. http://www.ptsnorfolk.co.uk/100820/info.php?p=4  Trades as gten98.

Army Radio Sales - Ive not had direct experience of these, but I include them to give them a plug, since ive been nicking their photos! http://armyradio.com/Clansman-Radios/

2012mdlradios - Occasional ebay seller, real nice chap, will go out of his way for you!  (thats not a link im afraid, but search on ebay for him)


The sellers above will kit you out! Incidentally, if you are one of the above sellers, feel free to, ahem, 'reward' my promotion of your business! Theres still some odd bits im looking for...

My remaining kit wishlist

Standalone Loudspeaker and connecting cable
CRS/LR box and connecting cable
Audio extension cable
PRC-350 battery extension
PRC-350 carry straps
Hand Charger
Bench/vehicle Morse Key
JAMCAT unit to CES
couple of chassis mount 7-pin audio sockets
Handset pouch


Feel free to just drop any of the above into a box and ship to me!  ;-)

Tuesday 9 August 2016

Charging PRC-349 batteries - Jig Needed

One thing ive found so far with these PRC-349 battery packs, is that its not easy to get crocodile clips to stay attached to the terminals! And with several dozens of them to charge and test, I need a better way to connect the charger.

What I need is a jig!  Luckily, these batterys have a bolt that runs through the middle of them to secure them into the radio, si im thinking a piece of plywood, with a hole and a nut embedded for the securing bolt. A few bits of wooden moulding to form a frame, and something for the contacts. I do have a bag of 'upholstery nails' which will probably do for that. These are brass dome head nails, so hopefully a pair of those in the plywood, and then the charger connected to the pointy end!

I also still need to work out a sensible charging/discharging regime for these that will condition them within a sensible timeframe each, but also keep up a decent capacity.

Monday 8 August 2016

Getting a bit further with the PRC-349 batteries!

Finally today ive finished giving my 300 odd PRC-349 batteries their initial terminal voltage check to sort the dead from the living, whether healthy or sick.

The dead battery packs
Out of around 300 batteries, about 70 show a decent terminal voltage, with a further 50-60 or so showing between a couple of volts and around 9V, so possibly recoverable. Four proved to be good Lithium primary packs, and one a usable dry cell cassette.

Left - possibly recoverable, right - reasonably good
Before being consigned for recycling, the dead packs are being checked for any decent, or at least usable, terminals, which im removing for replacing bad terminals on otherwise good packs. Likewise seals and decent metal shaft thumb nuts are being saved.

Recovered terminals
I will also save three or four dead batteries that have exceptionally good cases, for building eliminators.

Once all this is complete, I will select a few packs to keep for my PRC-349s, and the rest I will sell on at a price just enough to break even.


CHOTA this year from Selby Abbey

This afternoon I met with the vicar of Selby Abbey, to discuss the possibility of putting on a Churches On The Air day station,

Subject to some stringent timekeeping and non-interference (audible!) due to other events on the day, we have the go ahead. It is rather short notice but fortunately CHOTA is a single band event so equipment is simple and antennas even more so.

Ive already applied to Ofcom for the Special Event License. Im hoping we will get GB0SA (Selby Abbey) if there is enough time, if not we will fall back on the club call MX0TSE.

The Abbey is a wonderful building with fantastic architecture and history, well worth a visit (its free!) and great value refreshments! Its one of my favourite places and it will be an honour to operate from there.

http://www.selbyabbey.org.uk/index.html

CHOTA this year is on Saturday 10th September 10:00 - 16:00 BST.

Tuesday 2 August 2016

Clansman Manpacks for Amateur Use - Part 5b

PRC-320 HF Antennas

No mucking aboot, straight into it! For HF, were talking wire! At least, mostly...

SO, you have spent your hard earned shekles on a PRC-320, but been slightly taken in and its body only. You've collected up a battery, and a handset, now you need an antenna,

The basic starting point is the whip. This is an interlocking sectional antenna 2.4m long. However, it cannot be used directly with the radio, instead it requires an antenna gooseneck adapter. This is a hefty spring with a circlip secured hole for the whip, and a rod for the antenna socket of the radio.

PRC-320 Antenna Gooseneck adapter
Just like the one above, which incidentally im selling on ebay [eBay item number: 272308793412] for a very competitive price. This allows you to position the whip at various angles as required.

All well and good, but you wont get very far on just the whip. Thats not to say you cant make contacts - I had a QSO with a German station on just the whip on 40m from my workshop, and Bob M1BBV did rather well into the States on it on 10m. But, there are ways to make it better - Groundplanes!



The top one is the cheapest, but also a bit fiddly to use. A short wire connects to the -320's ground stud, and the four 9m long wires are unwound and laid out in a cross around the radio. The lower spool is a more up to date version and each wire is on its own little spool.

Now, you cant help but have noticed, unless your set hasnt got one, that theres a tuning chart on the radio. This tells you the settings of the built in TURF (ATU) for various antenna configurations. You will notice it gives values for the 2.4m whip, but also 5.5m and 7m verticals, end fed wires, and dipoles. Ah, dipoles, so now you understand why theres a removable coax link on the back of the rig!

Lets stick for now with the verticals. Remember that odd bit of wire with the 5.4m mast kit? Pop it on top of the mast, and thread it through the little hole in each of the guy plates. Now, look just below the antenna socket on the radio, theres a little spring terminal. Press it, and stick the pin on the end of the wire in the little hole - voila! You now have a 5.5m vertical antenna! You should, of course, be doing this with the above groundplane also attached.

So, whats the 7m vertical mentioned? Well, before putting the mast up, stick the 2.4m whip into the hole in the little tube that the wire is attached to on the top of the mast- 5.5 + 2.4 = er, about 7m!

With your PRC-320, you should also have obtained for yourself a 20m coax lead, a dipole center, and two spools of Clansman braided antenna wire. From these, come your end fed and dipole options. Notice that the wire on the spools has various colours and numbers of tie-wraps on it - these are length markers! Unwind the amount of wire needed according to the tuning chart, pass the end through the hole on the dipole center and into the terminal (or direct into the radio terminal if an end fed), pass the wire at the spool end through one of the tight slots on the spool, to stop it unravelling. Thats your antenna element. Do the same with enough of the cord to pull the wire up over whatever support your using (if that the 5.4m mast, then thread the cord through the guy plate holes and around the tie-off plate).
Antenna wire spool
I wont go into all the dipole and end fed antenna variations possible, as these are all in the back of the PRC-320 user manual, which surely you have downloaded and read by now? No? well why not?

For most of the antenna systems mentioned in these posts, if you trawl back through this blog you will find example pictures. There are also 8m and 12m masts available, but those are getting a bit too unweidly to be classed as man portable!

And, really, thats about it! From this short series of posts, hopefully ive explained the basics of getting set up to use these fine green machines for amateur purposes.  I dont intend any specifc posts about actually operating them though! Working that out for yourself is part of the fun! I will however, do one last post, no. 6, if you have the stomach for any more, and just mention a few of the other little bits and bobs you'll find you cant live without!

Clansman Manpacks for Amateur Use - Part 5a

Bear with me (grrrr!) - we're almost done!

So, so far we've talked about which of the Clansman series manpack radios are suitable for amateur use, what you'd need to get one powered, and how to actually listen and talk on it if you have one (I offer no guarentee that theres anyone listening!), so all thats left is to discuss the basics of antennas for them.

Now, as these are the man portable radios, the antennas i'll mention are also man portable. The general operational doctrine in the field was usually that, with the exception of inter-section comms, the manpack would be talking to either a vehicle mounted system, or either a fixed or field commcen (communications center) which could be a couple of 12m masts and tents, an RN ship, or something a little bigger like DHFS Forrest Moor with its huge HF log periodics. The onus often, especially for HF, being on the more capable station taking the brunt of the link.

I'll start with the PRC350, and move on 'up the chain' as it were

PRC-350 Antennas

The PRC-350 has a bayonet fitting antenna socket for what are termed 'battle whips'. There are two common types, with corresponding differences in performance. The first is a 'rubber duck' type flexible 60cm helical antenna. This has an advantage of being pretty much indestructable, but of course not a great range! More useful is the 1.2m sectional whip. More rigid, but with a sprung ball and socket mounting, this comprises four tubular sections attached with an elastic cord.

0.6m flexible battle whip

1.2m sectional whip

Both of these are ok if your actually carrying your PRC-350 on your back or hip. Often available for very little money, but probably of very limited use, is the 'trailing wire' antenna. This is a 1.2m long length of braided antenna wire and a bayonet connector. Its tactical use can be appreciated, but for amateur purposes its little more than a curiosity.


Trailing wire antenna

So those are your usual antenna options for the PRC-350. Doesnt give you much leeway for your 2W does it? But, you may have noticed your radio has a dinky mini-BNC socket on it. We'll see why shortly,

PRC-351 and -352

The higher powered PRC-351, with its thobbing 4W, also has the same bayonet fitting antenna connector as the -350, and so can use any of the above antennas. But, it also has a BNC connector. This BNC is to allow you to use it with the big brother antenna, the GSA (Ground Spike Antenna)

GSA Kit
The GSA is a kit, available in Long or Short Rod versions, comprising a base matching unit, several antenna rods, coax lead, carry bag, and the namesake ground spike.The general idea is to fit to the base matching unit the desired number of push together antenna rods (number per frequency range is conveniently printed on the side of the base), attach this to the spike, ram the spike into the ground, and run the coax off to the radios BNC connector. In the tactical environment, this meant the antenna could be out in the open where it was effective, whilst the radio and the squaddie hid away in cover. Incidentally, if you have a short rod kit, just use double the numbers on the data plate.

The GSA antenna is essential if you have a PRC-352, as this cannot be used with the battle whips.

Have you discovered the odd 40cm coax lead that came with the kit? Yep, thats the adaptor for the mini-BNC on the PRC-350!

The GSA is not too bad an antenna, but its still rather low down. VHF likes height, so another kit is available, the EKGSA (Elevation Kit, Ground Spike Antenna). Supplied, hopefully, in its own carrying satchel, this kit comprises all you need to mount the GSA on top of the 5.4m mast (of which more later), or to hang it from a tree or other suitable support. The key to it is the set of measured coax cables and the mast mounting inductor unit. These between them provide an artificial ground for the GSA.

EKGSA kit
 There is also a 'long wire' antenna system available, but this never seems to turn up intact, rather the antenna wire spools show up but not the terminating resistors or feed inductors. Other antennas you will see are the 'pineapple' which is similar to the GSA but of a wideband design. This is not by any form of clever matching system, but rather by a terminating resistor! Not great for your measly few watts. Another you might see for sale is the 'ground mounted monopole', commonly known as the washing line, for reasons that should be apparent to anyone whos ever used a rotary clothes airer! Again, probably not of any great use, but if you have the money, by all means get one.

To use the EKGSA at height, if you dont have a nice tall tree with spreading boughs, you'll need a mast. The EKGSA (and many other antennas for the HF side of things) are designed to be used with the 5.4m Fibreglass mast kit.

5.4m Mast Kit
It is true that these can be erected, as the manual states 'by a single well trained soldier' but its far easier with two or more people! Six interlocking thick wall fibreglass tubes and two sets of three guy strings, plus five ground anchor pegs. There should also be a odd looking short tube with a wire attached, why, we shall see when we talk HF antennas.

Im going to put HF antennas in their own post, as theres more options there than with the VHF kit.