Saturday, 24 September 2016

The Full Monty

Well, after being shouted at from both ends, Hermes managed to find my missing parcel and deliver it on Wednesday. This contained all the remaining Clansman items from Andy in Glasgow. I left it where it was in reception until lunchtime on Thursday, when I summoned up the energy to carry the box to the car!
Hmmm, goodies

It turns out that theres two 4W SURF units, and not a 2W SURF as I had imagined. Not that that makes any difference. The Free Standing Loudspeaker, there in the middle, was what the whole deal was about!

After a few tests and checks, Ive decided that the PRC-350 from Andy is actually in better condition externally than the one I already had, so I have swapped the brand new antenna connector over and made this one as good as possible.

The naked 350

To do so, and be sure the antenna contact was properly made, involved opening it up. There was a dent in the back cover, so I removed the PCB from that half and knocked that out. I had to open it up again after fitting the antenna connector, and fit the seal i'd forgotten the first time!

This meant that I could get onto testing everything. The loudspeaker works brilliantly, but its volume knob was a bit rough and knocked about, so I swapped that with one of the knobs from the Amplifier box. It could do with a bit of a paint touch up in places, and on the stand.

Of the six PRC-349 sets, I found two of the earpiece and throat mic sets faulty. Not a big issue for me. One of the radios however, seemed to be faulty.

This radio would work ok in NOISE ON (*) mode, but not receive in L or W modes, unless it was close to the transmitter. This led me to suspect a squelch fault. So, I popped the cover off, did the same to a working one, and checked the adjustment positions. Sure enough, it wasnt in the same place as the working one, a quick tweek and that radio now works just fine.


I did notice that two of the antennas were better condition than the ones on my mint pair of 349s, so swapped those. Likewise, some of the dust caps got moved about!

With all the kit tested apart from the two SURFs and the Amplifier Box (which I cant test), I decided to have a look at the two extra 'faulty' radios. Both have one fault the same, i'll come to that in a moment. But one had a fault which I just couldnt believe when I saw it.

The photos below show show the faulty one on the right - can you see problem?


The entire 0v connection - thats a nut, bolt, washer, solder tag and ceramic capacitor -  were missing! Just simply not there, and the -ve battery terminal looked like it had never been connected!

Closer look - wheres me solder tag?
This was a simple fault to repair, but time consuming to find a suitable nut and bolt! The two radios are still faulty, but I know the problem. The protection link, a short length of thing tinned wire, is in both cases missing.


I need to find the right sized wire in order to repair these links. Theres no rush to do that though.

The rarely seen underside of a PRC-349 radio



Wednesday, 21 September 2016

Let Battle Commence!

I now, thanks to Andy in Glasgow, have enough PRC-349s to equip if not actually a small army, at least several sections!


The above came as part of a deal for several ancillaries and a number of BATCO wallets. Sadly, at present, the shipment containing the other items, which include the Loudspeaker, Free Standing, which is the main item I wanted, is lost somewhere within Hermes' system, having been marked as delivered but not actually dropped off. Were chasing them up on that!

Luckily, the BATCO wallets were in the shipment that did get correctly delivered



Monday, 19 September 2016

Heard by DP0GVN

Wow! Just checked on how my current 20m 2W WSPR activity is going - Ive been heard by DP0GVN - in Antarctica!



Thats not bad for about the same power as a flashlight bulb!

Station back together again!

Ive finally found time to put all the kit used on GB0SA back in place in the shack. Phew what a task! Setting up a special event is much easier than setting up a fixed station! For a start, on a SES you'll typically be using a desk facing the public - so all the cables are exposed and easy to access, not so in the shack!

Well, I now have it all back together, and despite a few hiccups, such as having three booming audio feeds of the same WAB net for a while, having no spectrum monitoring until I figured the settings out again, and having no PC audio output to the radios, nor serial PTT control, ive managed to fix that and am having a bit of a play on 40m WSPR.

After a lot of fiddling to get set up, my first 33dBm transmission (2W) has shown up on the WSPRnet map as being heard by - DC5AL-R, DC7JZB, DF2JP, DF5FH, DG2HSI, DK6UG, DL0HT, DL1KAI, DL4EAI, DL6OW-R, F/PE3ES, F/PE3ES, G4FBA, GM4SFW, LA1NRA, LB0K, OE2WNL, ON7KB, PA0MBO, PA4MSA, PA7T, PI4THT, SWL77KRS

So it seems to be working! I'll probably give it a few bursts on 40m and then move up to 10m

Saturday, 17 September 2016

Radio Bergen - Frame Back Panel Complete

After the final resize, and some more careful measurements, the back panel is now complete. The last job (other than some future filing and sanding) was to form the slot for the main strap of the Bergen to pass through.

This strap is intended to come through between the radio body and the battery when used for clansman, so required a slot cutting in the middle of the panel. But, it should be noted that this strap is not actually central! Its a couple of cm off the center line.

Cutting the slot meant another round of pilot hole drilling, hole widening, nibbling, and ultimately a lot of hard work with a file!


And this is how it looks strapped in! The next stage is to decide on the height, and to form up and attach the top/sides as needed. I dont yet know what form these will take, but im thinking maybe a top panel to carry antenna connections, a bottom panel to act as a battery tray, and a couple of sections where the plate widens.

As for the front of the frame, im not sure. I dont really want a solid plate, due to the need for ventilation. Im thinking perhaps a framework of square section rods.

Radio Bergen - Frame back panel

So, it seemed the easiest way to start, was to measure the Bergens internal dimensions, and then cut a back panel from sheet metal to these, and see how it fit.

If youve ever tried to measure the inside dimensions of a bag, you'll know how hard it is to decide what the actual numbers are! But, I had some figures, and I had a nice clean sheet of galvanised steel (the top cover off of an old video encoder)


Clearly my hacksaw was no use for cutting the long sides! So, most of the work was done using the nibbler. These are great tools, and with care can get right up to the mark and do a reasonably straight cut, reducing the amount of filing needed. The downside is they can be hard work on the hands


As shown above, the panel is almost in shape, with the reduced size end (where the battery would be) to allow the battery strap to be used to secure it.


As i'd cut this from an equipment rack, this left me with a nice 50mm side, which helped see how the frame would fit. Unfortunately, as can be seen by the above photo, at these dimensions it was a little too big. It would have fit at a push, but the corners would have worn through the fabric eventually.


So the side had to go and 10mm be taken off each side. I could have just done one cut and removed 20mm from one side, but although that would have reduced the pain and blistering, it would have displaced the lower section. So two cuts it was. I also increased the lower section depth by another 5mm to give some clearance to the battery strap. On the above photo this has all been done, but you can see that the bottom edge still needs more off.


And then the final sized back plate. 10mm off the bottom edge. Ive put my DX-70TH on it as an example of the idea, and it fits - heatsink to end of tuning knob - just within the diameter of the frame.

One task remains at this stage - a slot needs to be machined about 2/3 of the way down (roughly where the right hand side of the radio is) to allow for the passage of the main strap.

Modern Transceiver Internal Frame Design for Rucksack, Radio, DPM, IRR

With the accelerated release of Clansman radio surplus by the MoD, which nowadays seems to consist much more of mixed stillages of random items rather than stillages piled up with actual radios, or seemingly whole pallets of NOS 4Ah batteries, the once quite rare 'Rucksack, Radio Carrier, DPM, IRR' seems to be more freely available.

These are the ideal way to carry your PRC-320 or PRC351/352 (or PRC-350), if you have a requirement for comfort over distance. If your need is to display the radio then your better off with a GS carrier frame, but I wouldnt advise using that much further than the shows tea waggon!

I now have three of these Bergens. (for those who dont know, Bergen, a town in Norway associated with British Army arctic warfare training, gave its name to an early form of rucksack, and hence since has become a colloquial term in the forces for any rucksack. Not to be confused with a 'Norwegian', or 'Norgi', which is a fleece jumper, and in itself should not be confused with a 'Norgy' - a large insulated food carrier, usually containing either 'Range Stew', ie everything left over from breakfast, 'Coftea' a mix of coffee and tea, 'Screech' - fruit and nitric acid flavour cold drink, or frequently all three!). One of these has my PRC-320 in it of course.

As much as I love the Clansman CNR Manpacks, they do have, lets face it, a number of drawbacks for typical amateur use. First among these is of course the weight, but a very close second is frequency agility, and coming in at third place is transmit power.

Lets compare a PRC-320 to, say, an FT-857. The Yaesu is clearly far more advanced, and much more pleasant to use for general tuning about, working split, etc etc. It is smaller and lighter. But it suffers a major drawback for activities such as SOTA - its fragile! Now, how great would it be to take a radio like the 857 or its ilk, an ATU, and a modern battery system, and protect them in a nice convenient padded backpack?

This is what I intend to do with one of my Bergens. This leads straight away to a problem - the Bergen is intended to carry the radio strapped in. Modern radios would just not fit this way. A frame is needed in order to mount the radio and other equipment.


Above is my sketch of what is needed. The height measurement is based on the strap for the PRC-320 - this is how high it goes before the reinforcing for the buckle. I intend making this using square aluminium rod salvaged from equipment racking. It might be an open frame, it depends on how strong it turns out. The idea is that inside the frame, the fixings could be adjusted to suite whichever equipment is to be fitted.

One thing I may do though, is reinforce the top right of the frame and fit a genuine Clansman PRC-320 antenna rod socket. This will instantly open the system up to use the Clansman 2.4m antenna and wire antennas.

I suspect that at least the bottom of the frame will require a solid plate, to prevent the soft Bergen from pushing in on the equipment.

Monday, 12 September 2016

GB0SA - Another great CHOTA day

This saturday passed, was our Churches On The Air day station GB0SA from Selby Abbey.

I'd got all the kit sorted and crated up the evening before, and since the abbey is only just up the road, even had a short lie-in! Myself and Sam, with a fully loaded Ford Fiesta, arrived just on 08:30 as the verger was opening up. I knew Steve G7TAO was en-route somewhere, as i'd heard him call me on 2m, but had been too weak to reply to. However his third call, as we were parking up, was S9 from Camblesforth, around ten minutes away. At around this time Mike G4IJI also arrived.

Shortly after, the verger unlocked the main doors and we were in, shuttling the kit. It was a bit eerie being in such a place in the dark!


After a bit of on the ground assesment, we realised we could put up a dipole using just the Larksput mast, and use the trees etc for tie offs, which saved having to erect the 5.4m masts. The Clansman antenna wire, tied off at 8.5m per leg, analysed at just under 3:1 SWR. Close enough to not worry about and to let the ATU take care of the match. 

With the main coax feed routed via the vicars office window (and seemingly taken in as I fed it from outside by the hand of God!) we set up off to the right of the main doors. I appologise for my lack of correct church terminology here, i'll update that later! Mike had us organised for refreshments, and settled in for a days radio


A 100w out on 40m LSB, with Steve at the mic. Our first session was 'search and pounce' to mop up any other CHOTA stations we could hear. This was our operating situation until just before 12:00, as by then many of the guests for the first wedding of the day were turning up. The choir practice had luckily caused neither us nor them any problems, but with the best man chain smoking his way back and forth, we decided to pull the plug for the morning and go in search of lunch.

A rather good fish and chips lunch was had at Mr C's  http://www.mistercs.co.uk/  and it kept us out of the rain. After, we made our way back to the abbey, stopping only to allow Steve to raid Mollie Sharps cheese shop  http://molliesharps.co.uk/  (you know, I put in all these links for great local businesses yet my inbox remains devoid of money off vouchers...)

The afternoon session saw us go fixed frequency to call CQ. The band was in a rather funny mood, very deep QSB, with long periods of nothingness followed by flurries of calls. The number of CHOTA stations seemed to die down, but skip lengthened and we found ourselves working into Europe.


Since I had the PRC-320 as reserve radio, we took that outside and ensured all three operators also had a chance to work GB0SA! Unsurprisingly, signal reports were good!


Just before 16:00, and with the guests arriving for the second of the days weddings, we shut down and packed up. The equipment left where it was for the duration of the wedding, whilst we struck the antenna system and packed up the mast and feeders. With nothing left to do but wait for the photos and the bride to leave, Mike made his way for his train. As soon as the bride had finally left, myself, Sam and Steve moved the remaining equipment and made sure all was as we had found it.

A total of 30 QSOs were made (not counting our own!), of which 10 were other CHOTA stations. Best DX was just south of Geneva at 621 miles.

My thanks go to Steve G7TAO and Mike G4IJI, to Sam for his help shifting stuff, and to Canon John Weetman and the staff of Selby Abbey for allowing us to invade the church for what to them was probably a pretty bewildering reason!

Friday, 9 September 2016

GB0SA CHOTA Selby Abbey tomorrow!

Less than a day to go! We have access into the abbey from around 08:30, so all being well should be on air from not much after 09:30. Officially we start at 10:00. (bear in mind these are local, BST times!, knock 1h off for UTC!)

All the equipment, save for the basic toolkit, is crated up and ready. Each box for a different part of the kit, so fir instance the actual radio equipment and its PSU, ATU, etc, and the station paperwork, is in the green crate


Mains power, RF test load, and safety equipment, in the blue crate. The purple box is coax patchleads, extra feeder, and rigging equipment. The valise contains the guy kit for the main mast.


Yes, the 14lb sledge hammer is a bit overkill! It should be a 4lb lump hammer but mine doesnt have a shaft on it at the moment! The main RF feeder is on the cable drum.

The masts at the moment are just propped up. The two 5.4m kits will fit in the car, but the main Larkspur 27ft mast has to go on the roof.


Not shown in these photos is the signals satchel containing the actual antenna! Yes, I very nearly forgot the aerial itself!

Now all thats ready to go, I have a little while to look into another project. The radio bergen below. I need to establish the internal dimensions of this, in order to design a carry frame to go inside that will hold a modern HF transceiver,  ATU, antenna mount and battery system.


This is actually my 2nd spare, and is quite old. I'll be selling this one on eventually as surplus to my needs.

Thursday, 8 September 2016

Trip To The Tip

I have now, finally, finished testing all the PRC-349 batteries and put aside only those that will hold a charge. This doesnt mean they have a decent capacity, of course, but it does mean they will work to some extent.

This left me with two big domestic recycling boxes full of dead batteries!  These have now gone to the tip, and after some discussion with a naturally dubious dustman, have been disposed of into the care of North Yorkshire HWRC.

This has created a bit of much needed space, ready perhaps for the next intake of radios!