question Military Radios

This could be a really stupid question, but..... I have just seen the thread by Airportable about passing his ham radio licence, and congratulations to him for that, and it occured to me that as a lot of our members own things like FFR Land Rovers etc complete with Clansman or Larkspur radio gear in the back, are they still able to use them? The radios that is, and do you need the licence to do so

in a word, no. If I understand it correctly,you cant use clansman without a radio licence, also they put out to much power when transmitting.

You definatly cant use the 344, thats airband only.

Andy (arportable) will be able to explain more

Mark

Err. thanks Mark!! Good question asked, still need to get our heads around the Clansman radio manuals and the Ham licence facts and figures.

The main reason we did the course was to find out what the operating practices and procedures regarding transmitting are. We had been told so much by one person and another, and in no way would we have used the kit. The fine can be very large, and I understand kit and vehicle could also be taken away and crushed.

We did the foundation course, only allows a max of 10W between restricted frequency bands.

To try and keep simple ,with VHF a dedicated calling frequency is used which you move off( so it is kept free) Problem with Clansman frequency's are pre selected. We also need to get kit so we can be 100% of the RF power, a 351 may even be too much and a 352 certainly will. I think options for VHF may be nil. HF may be more of a chance (the reason 320's are so expensive)

To make it more complicated a full licence will allow you to do much more regards RF power.

Any way we want to sort it all out with a friend or two who really know what they are doing before we do a thing. BUT most clansman radios have the option of being used as a 'phone' with D10 wire anyway.(Good for command tent demo's) Another point, radio ham 'speech' does not sound miltary, I would like to use SLIDEX:nut: (using this type of sysem over the air waves is also banned). So using this system I would have to talk to my self, if we can find out how it was used, or over D10.

Larkspur radios I know nothing of. Another little point, RF burns from antenna!!:shocked:. A more knowlegable person may explain.

Any radio hams, please correct me on any point. We are most intrested to demo our displays as 'living history'. Andy.

It is not so much about power as the frequency they transmit on. Amatuer Radio licence only allows transmission on very specific bands. For each band there is a Max and Min frequenccy.

Google Amatuer Radio Band Plan....then compare with Clansmans fixed (crystal controlled???) frequecies.

If you can get a version that will transmit within the allocated freqencies for that band, then at face value I can't see why they cannot be used, by a licenced amatuer providing the use does not move outside these frequncies.

Many thanks for the replies and info, guys. I'm not a radio man myself, as such, but you see all this kit on show at the various displays during the year, I just wondered if it is still useable. I remember back in the day being put on radio stag when on exercise, and tuning in to alsorts of other transmissions in the small hours when the regiments net was "off air" Slidex was fun as well if you could remember which start codes to use.

Thanks again

I think GCHQ might have a word if anyone starts messing in the Military band (Radio)

Slidex was fun as well if you could remember which start codes to use.

 

Andy.

I think GCHQ might have a word if anyone starts messing in the Military band (Radio)

Seem to recall it's all controlled by OFCOM now..?

To muddy the waters still further, it is possible to get a transmission licence for a one-off event, but it can be quite expensive! (probably not sensible for individuals, maybe for large events though). You have to specify what frequencies, time and location(s), then they check if you would be interfering with normal users and grant it if you won't.

You can find a lot out on their website but as others have pointed out the penalties can be severe! (including payment of consequential damages, there's a not-very-funny story about that! :shocked:)

Stone

Isn';t OFCOM to be part of the much vaunted Bonfire of the Quango's?

Isn';t OFCOM to be part of the much vaunted Bonfire of the Quango's?

Please Sir, may I be the one to light that bonfire? Please, please!........

Seem to recall it's all controlled by OFCOM now..?

 

 

 

Stone

Andy.

Hi All

With the one reservation about power limits for Foundation and Intermediate license classes all of the Clansman radios except the 344 (UHF airband) and 349 (low VHF) cover at least one amateur band and can be used by a licensed radio amateur within the amateur bands that they cover - for practical purposes this means FM in the 6m (50-52MHz) and 4M (70MHz) bands for the 350, 351 and 352. A 350 (2 watt) or 351 (4 to 5 watts) should be fine for foundation users on these bands. The main catch is that on 6M the channel spacing for amateur FM is 20KHz whereas the Clansman sets have steps of 25Khz, so only 51.3, 51.4, 51.5, 51.6 and 51.7MHz are really usable within the amateur FM range. 4M is 12.5KHz spacing so every 2nd channel is useable.

You should probably (looking forward to the intermediate and full license requirements) look to get a power meter and frequency counter to independently verify the output and tuning of the sets. Most local radio clubs will also operate a "rig clinic" where you can take radios to test equipment once in a while too.

Here in East Suffolk most of the Clansman VHF users seem to settle on 51.500.

The RT353 can be used at full power by intermediate and full license holders on these bands (it is a 50 watt set) - I'm not 100% sure of the foundation license conditions as to whether one must not operate above the license limit or must not use kit capable of it - if the former is the case and you have a power meter to prove it, I would have thought any of the larger sets (320, 321 and 353) can be used on their low power settings.

On HF the RT320 and RT321 both have low power settings at 5 watts so should be useable. Their high power outputs are about 30 and 45 watts so should be covered by an intermediate license. These cover all of the amateur bands between 2 and 30MHz although because they offer upper sideband only and the amateur radio convention is to use LSB below 10MHz, they are most useful for long range contacts on 14, 18, 21 and 28MHz.

For display purposes am HF set on receive and a speaker is probably the best / most interesting thing to have, I would suggest.

My own station is a 321/322 high power setup for HF and a 353 for VHF and I do have a 352M and a 320 for mobile use.

Regards

Iain

73 de G0OZS

(Part 2 after a coffee refill)

Operating practices:

Amateur radio procedure (such as it still exists - I must be becoming an old fogey ) is largely based on marine morse practice (since that is what was around to copy when amateur radio started before WW1) and that has been carried into voice operation. As such Amateur and Military VHF speech procedures are rather different. We are of course very different from military operators in that we talk mostly about our equipment and location, make general calls and tune around listening for other stations calling, tuning is one painful aspect of the Clansman sets that use dial switches for tuning. I generally find myself using a dial tuned receiver (Larkspur R210) to search on HF and then set the 321 to the same frequency to call back.

Larkspur Radios:

As with Clansman those sets that tune across an amateur band can be used in that band subject to power limits. These sets are based on 50KHz (No.2 versions) or 100KHz (original) for VHF so channel selection is more of an issue - the VHF B sets (B48 etc) should be low enough power for all licensees but the C sets are probably for intermediate and full licenses. I personally have no experience of operating the Larkspur VHF sets - but they are mostly fixed crystal controlled channels on the manpacks and continuous tuning (with a calibration aid) on the vehicle sets. The ultimate Larkspur reference is Louis Meulstee's site

http://www.wftw.nl/larkspur/larkspur1.html

On HF I know several amateurs using the C11 or C11(SSB) which produce a fine AM signal on the 80 metre (3.5-3.8MHz band) - the original valve C11 is quite reliable, but the C11 SSB (very early transistors) really needs a repair workshop in tow! I have the associated R210 receiver and can recommend it.

RF Burns:

These are deep under-the-skin burns due to RF heating - they require a lot of power (50 watts plus) and contact with a very badly set up antenna system or the vehicle attached to it. You wont get one of a Foundation license power set - and even a RT321/322 at 300 watts is safe using balanced (dipole) antennas. Great care as to earthing is required when using high power sets with a whip antenna and the vehicle as ground, however. the only times I have had burns is when an earth connection was broken and the microphone lead became live at RF since it was acting as a counterpoise (artificial earth) wire.

Hope this helps

Iain

73 de G0OZS

Part 3 - use of D10 cable

Most of the larger Clansman radios (RT349 and RT350 excepted) have the facility for remote operation over D10 field telephone twin wire out to a distance of 3KM or so. The RT320 requires an external interface box (CRL/R) and the other sets (321/2, 344, 351/2, and 353) all have a pair of terminal posts, a wire stripper and a mode switch. The mode switch has settings

• LOCAL - for use as a radio with directly connected headset
  
• REMOTE - for use as a radio controlled by a remote operator over D10
  
• IC - for use as an intercom between the local headset and the remote operator over D10
  
• CALL - sounds a tone in the remote audio equipment
  

The remote operator may use either a telephone handset (a special remote version with insulation piercing terminals behind the microphone and a call button) or a remote combining unit (which allows use of 2 normal Clansman headsets to control either of 2 radios using a pair of D10 connections). The Adapter Telegraph Radio (ATR) can also be used as a remote interface box, and the Larkspur era loudspeaker gun control (which has a built in amplifier and 2-wire interface) can be used on receive only.

Note that the polarity of the headset, RCU or ATR connections matters - the radio will squeal if they are reversed.

I have read (but not tested) that it is actually possible to use the remote interface of the 321, 351 and 353 as a kind of crude telephone exchange by connecting multiple headsets to the same radio - in that case whichever handset has PTT pressed will be heard by the others.

Hope this helps

Iain

73 de G0OZS

Thanks Iain for your very intresting reply. We will study with intrest.

We were lucky that we did the course with the cadets, hence we have the invite from the CO to take our Landi's, kit for further help in setting up and also they have a well set up radio shack with all test gear etc. We may even get the chance to go on 'patrol' as signal opperators :nut:.

Andy.

For display purposes am HF set on receive and a speaker is probably the best / most interesting thing to have, I would suggest.

What are you supposed to do if you accidentally pick up military transmissions from people still using Clansman instead of Bowman? I know when we were intercepting unaware operators we needed to have a RIPA license which was a pain in the bum to acquire!

Stone

Hi, dont have any old paperwork, info on Slidex do you?

Andy.

Took nipper to Bovvy a couple of weeks ago. He did codes and cyphers as an optional module on his MMATH degree, so he entirely understood my ten-minute lecture on Slidex using only the pad and sliders visible in a display cabinet.

Not paperwork, but here you go.

Slidex dates back to the Second World War (1944 rings a little bell: maybe a date I once saw on a card?). A Slidex pack consists of a wallet containing Slidex cards and horizontal and a vertical slider. The cards must have been about 15-18 boxes (I forget) wide and down. The sliders were graduated so that each line on the slider matched a box on the card. Each slider had IIRC 24 boxes. Spare cards went into a pocket in the wallet.

Encoding the sliders involved reading today's Slidex code from the signals instructions and writing the 24 letters (no India or Quebec if memory serves) into the boxes in the order given. 24 letters across the page and 24 letters down the page.

The code also gave a number sequence for each slider. These were inserted into a corner of the first half-dozen or however many boxes. I think ten digits were issued and the first six boxes had spaces for the numbers. The extra numbers went into doubling the numbers available for the first boxes.

So that if the number sequence, horizontal or vertical, was 0857634219, the numbers went in that order into boxes 1234561234. So that encoding the slider at 0 was identical to encoding it as 4, 8 as 2, 5 as 1 and 7 as 9. If memory serves. But because anyone without the codes couldn't tell which box a number represented, he couldn't make use of the fact anyway.

The sliders were then installed into runners, one across the top, one down the left-hand side.

Encoding a message started by randomly moving the sliders left/right and up/down so that the letters above col 1 and beside row 1 varied from message to message. The first encoding was to write down these two numbers (like map reading, codes always worked along the passage and up the stairs). So the number in the horizontal slider was followed by the number in the vertical slider thus, say, 74.

The person decoding would then be able to set his own Slidex pack to the one-time code by aligning his own sliders to match.

A Slidex message always started on Slidex Card 1 (there were IIRC about 100 cards, all with different information and it was possible to encode for example, Go To Card 91 in not many bigrams), because Card 1 was the obvious place to start. After 30-odd years, very few people had more than Card 1 and those who did have a few more didn't the same few as anybody else, so messages rarely moved off Card 1, which was a general purpose card anyway.

Encoding the body of the message involved finding a word, phrase, letter or number and taking the letter bigram (one from the top and one from the side) that identified that box. So a Slidex message would be constructed like:

74 SU ND ER LA ND AF CF TM

The code was written on the sliders in chinagraph pencil, to be rubbed off at 2359 and replaced before 0001 with tomorrow's codes. I could quote a certain TV celebrity meerkat, but I feel it's been overdone.

Basically all the various codes worked along these lines to create an uncrackable one-time coded message (provided the code strings did not fall into enemy hands, in which case new codes were to be issued by hand). The cards were IIRC restricted, but like I said, more were lost than remained by the end of Slidex's life and you can guarantee that the Commies knew the contents of every card. But this was useless without the daily codes.

The codes used included Griddle (taught on my radio course in 1975), Universal Griddle (that enhanced Griddle - taught in 1976) and Mapco (that replaced Universal Griddle in the late 70s). ISTR that Batco (that replaced Slidex in the 80s below formation level) worked along similar lines but was somehow a two-stage encode / decode. Despite being the last code I learned and used, Batco is the one I cannot clearly remember. The Griddles and Mapco were purely for sending map references in code. Mapco and Slidex allowed fully-coded messages, though good practice stated that only the part(s) of the message that needed encoding got encoded.

I think they are all redundant now as everyone on ops uses Bowman. So much so that I was recently told that IKTUGWEFA can be reintroduced, since the value of IKTUGWEFA to us will be far more than to an enemy who won't be able to pick out IKTUGWEFA from a coded message anyway.

Since you ask. Back in the day, everyone used a similar callsign structure, so that when different units combined in a combat team or battle group, there might be B Coy of one infantry battalion, B Coy of another, B Sqn of an armoured regiment, Swingfire from B Coy of one RA regt, field arty from B Coy another RA regt, etc. Every one of these might reasonably have say a callsign 21.

To tell them apart, call signs were prefixed with an arm indicator. In order of precedence on a cmbined units net:

India = Infantry

Kilo = Infantry alternate

Tango = Armour (tanks)

Uniform = Armour alternate (but invariably used by umpires)

Golf = Artillery (guns)

Whiskey = Arty alternate

Echo = Engineers

Foxtrot = Engineers alternate

Alpha = Air Corps

Bravo = airborne or special forces, hence Bravo Two Zero - even though arm indicators were dropped in 1982.

Thereafter arm indicators answered up in alphabetical order. This system was known as IKTUGEFA, until the need for an arty alternate, W, saw it renamed IKTUGWEFA.

In 1982 the OpSec cost of using IKTUGWEFA outweighed the value to friendly forces, so during a rewrite of Voice Procedure, fixed arm indicators were replaced by daily-changing issued within the formation, along with a total standardisation of what call signs were actually to be used so that the identification of a particular callsign unique to, say a recce regiment, did not identify that callsign to the enemy allowing them to determine what sort of net this was. There were eight vehicles in a recce regt close recce troop in 1982. The presence of a callsign 6xG (x indicates which troop of the close recce squadron) would tell you that this was probably a combat team command net. If the Commies were good and identified a battle group command net including call signs 2 and 3, this could well be 15/19H BG, because A Sqn was Close Recce and took call sign 6. This was a breech of OpSec, because the book said that C Sqn was to be close recce, and the medium recce squadrons were to be call signs 2 and 3.

Actually giving them IKTUGWEFA made identifying what was on a particular net a no-brainer, hence its scrapping. Now that operational nets are scrambled, IKTUGWEFA can work for us not against us again.

It's been many decades. This is how memory serves. If I am mistaken, I apologise in advance.

you will find that there was a lot of ex mill and pmr radios yoused on the amature bands ,till the modern sets became avalablein the late 70s it was the maine sorce of equipment .I still have PYE westminsters on 4 and 6 meter bands ,my hf recever is a 1155 aircraft set from the 40s got to make the ht power unit so that i can put my 1154 trasmiter into service .once you are on the air ask round and you will find that there is a wealth of info out there . good look Graham G1DNZ.

Thanks Graham.

And thank you very much indeed AlienFTM. That info is fantastic and a big step into the SLIDEX code. I have only ever seen a pic. of the kit/board. Will study with great intrest. We really do want to be able to demo. the system. Thanks again.

Andy.

Thanks Graham.

And thank you very much indeed AlienFTM. That info is fantastic and a big step into the SLIDEX code. I have only ever seen a pic. of the kit/board. Will study with great intrest. We really do want to be able to demo. the system. Thanks again.

Andy.

There are a fair selection of SLIDEX cards and associated docs in the WS19 group archive.

See: http://www.royalsignals.org.uk/misc.html

(Declaration of interest: they're mostly scans of my collection, and I'm one of the moderators of that group.)

There were two designs of wallet: the original "oiled cloth over strawboard" which had a very short life under jungle conditions: the whole thing went floppy as the strawboard got wet, all the metalwork corroded like crazy as they'd used aluminium and steel fastened together with brass rivets(!) and the code cards were just what mould spores had been waiting for. The later one was paxolin sheet, an oilcloth "wallet", and the metalwork was designed with rather more care taken over its electrochemical properties. They also found a high grade card stock and an anti-fungal varnish that mostly solved the water adsorption and mould growth problems.

Sliding cursors (3 sets in case you need multiple keys for different radio nets) are double sided (so you can retain yesterday's key for unbuttoning late-arriving messages) and made of _celluloid_ (cellulose nitrate) for ease of destruction if capture is imminent. KEEP AWAY FROM FIRE!!!

SLIDEX replaced CODEX & SHEETEX in late 1943/early 1944 and (if you'll excuse the unavoidable pun) soldiered on until it was clearly obvious to be useless against an enemy with computer assistance (during the Falklands war). GCHQ were requested to provide something better, and developed BATCO (which is virtually unbreakable when used correctly).

All SLIDEX cards in service prior to 1973 were downgraded to UNCLASSIFIED in the early 1980s, by the way.

Hope this is some help, or at least interesting.

Chris. (On the look out for SLIDEX cards that are not on that webpage - so that they can be scanned and put up there.)

Thanks Cris. Saved your link, looks like I will have to join.

The RT353 can be used at full power by intermediate and full license holders on these bands (it is a 50 watt set) - I'm not 100% sure of the foundation license conditions as to whether one must not operate above the license limit or must not use kit capable of it - if the former is the case and you have a power meter to prove it, I would have thought any of the larger sets (320, 321 and 353) can be used on their low power settings.

That's ironic. In BAOR, we were proscribed from using 50W on the UK/VRC353 (as we knew it) because the Bundespost felt it would damage their infrastructure. Since 50W would also blow the 20W adaptor on the mastheads, we were never tempted in RHQ or FHQ.

No, not true. One exercise in 1982 we were the first troops ever to exercise in the Harz Mountains National Park. We were under the nose of the Soviet Brocken listening station so it was the only time we ever didn't set our output to 16W. Until a signals unit, deployed onto the exercise with us, went into ESM mode to give us all a feel for operation during jamming. I had to physically remove the squadron leader's hand from the power switch to keep him off 50W, because I at least valued the 20W adaptor.

Of course it didn't mean the sabre troops in OPs, without masts and on the wrong side of the slope to talk to FHQ, didn't ever feel tempted to switch to 50W to get round local difficult working conditions.

Bazz?

Alien

I think the lower VHF band is now less of a concern to the DBP and its counterparts in other countries. The UK limit for full/advanced licenses is now 100W using CW or FM or 400W SSB on the 50-51MHz band and 100W on the 51-52MHz band - see:

http://www.ofcom.org.uk/static/archive/ra/publication/ra_info/br68r11/br68.htm

and German amateurs generally have higher limits on the bands they can use than we do. Having said that the 50-52MHz frequencies were only released to amateurs in Europe after most continental Band I TV services closed in the 1980s so it would probably have been more of a concern until then.

Regards

Iain

73 de G0OZS

Alien,

I can remember the exercise well, and can confirm that I used 50w on a number of occasions.