Larkspur intercomm

[tyler]

Hi could anyone help me , I am looking to have a larkspur intercomm in the Shorland but not sure what other Larkspur boxes i need other than the ones i already have, and do all Larkspur intercomms require a radio to be included in the set up

 

Also can anyone tell me if there any differences between the commandars and crewmans headsets, i have looked on http://www.wftw.nl but it just says they have different microphone, cords, junction boxes and plugs differ, so i was wondering if using different boxes or plog adaptors would sort those differences out, as I have got a compleate commandars headset and another set of headphones but i dont know if its ok to use all comanadrs headset or keep looking for a crewmans set/

 

 

i have this so far:

 

Interconnection Box LT 4-way No. 4

unknown make and model amplifier

1 commandars mic

2x headphones

and 1 or 2 leads

 

Thanks

[AlienFTM]

Hi could anyone help me , I am looking to have a larkspur intercomm in the Shorland but not sure what other Larkspur boxes i need other than the ones i already have, and do all Larkspur intercomms require a radio to be included in the set up

 

Also can anyone tell me if there any differences between the commandars and crewmans headsets, i have looked on www.wftw.nl but it just says they have different microphone, cords, junction boxes and plugs differ, so i was wondering if using different boxes or plog adaptors would sort those differences out, as I have got a compleate commandars headset and another set of headphones but i dont know if its ok to use all comanadrs headset or keep looking for a crewmans set/

 

 

i have this so far:

 

Interconnection Box LT 4-way No. 4

unknown make and model amplifier

1 commandars mic

2x headphones

and 1 or 2 leads

 

Thanks

 

All Larkspur intercomms require a radio to be included in the set up. This is your key. Clansman saw I/C built into the harness, but for Larkspur, I/C was a function of the A-set radios (C42, C13 etc).

 

I only caught the tail end of Larkspur and it was over 30 years ago, so everything is hazy.

 

On Ferret I don't recall there was any difference between a commander's and crewman's headset. There was only one. Function came via the J2 junction box (2-set). I believe there was a J1 and a J3 for 1-set and 3-set configurations.

 

The only Larkspur commander's harness I recall was for Scorpion. Scorpion was designed for Clansman, but in the 1970s UK plc could not afford both CVR(T) and Clansman, so MOD were offered a choice of either/or. They chose CVR(T) and Scorpions (and I presume any other CVR(T)s in the field before the advent of Clansman) were fitted with a hybrid harness that gave an approximation of Clansman function from Larkspur radios. Key to this on Scorpion was the (iirc) RSB2 Radio Systems Box 2-set which allowed crewmen to work one set through the left ear and monitor the other through the right. Live I/C was optional, again through the right ear, when using a Clansman helmet with a boom mike, which was compatible with the hybrid harness.

 

Both Clansman and Larkspur harnesses provided the commander's function via a long, thick umbilical cable that attached to a breastplate slung from the neck, but all these years down the line I honestly cannot remember which was which and what function each provided.

 

Hope this helps a little.

[andym]

That sounds very similar to the Abbot, which was updated to Clansman by cobbling a PRC351/2 on the existing Larkspur harness using an IBRA box.

 

The Wireless Set No. 19 group at www.royalsignals.org.uk have several Larkspur and other manuals which may help?

 

Andy

[AlienFTM]

Actually I forget. In the absence of a working I/C circuit, there was, for Scorpion, an Emergency Crew Control, a separate handset that allowed the commander to talk to the driver. It was battleship grey and looked like something out of 1950s TV football commentary or, as I put it, a grey toffee apple. I remember our C13 was out, the commander would talk to the driver (getting nothing back), then switch mike to speak to the troop on the B-set (B47). But we were new to CVR(T) and he had been a corporal in NI, posted to B Sqn on promotion and given troop lead while Rommel went through Sandhurst and his Crew Commanders course, so he was under a lot of pressure without an A-set on the Squadron Command Net.

 

He regularly tried to get the driver to turn using the B-set, which necessitated the ECC, but he used the Larkspur mike, telling the whole squadron to turn right here. Because as operator I was working the only set we had, I'd hear him next to me, tap him on the arm and gesture to swap mikes.Or he'd send LOCSTAT or SITREP to the driver via the ECC, which I couldn't hear, then curse furiously when he realised that he had been wasting his breath.

 

When we pulled over, I'd have to remind him (carefully: he was a sergeant and I was the New In Green member of the crew) to use the toffee apple (holds ECC aloft) to talk to the driver and the Larkspur mike (candy floss - okay it didn't look like candy floss but it was the best analogy I could come up with at the time) to talk to troop and squadron. In the end it came down to my nudging him and shouting (over the ambient noise) "Candy floss!" or "Toffee apple!"

[tyler]

Thanks for the replies,

 

the reason I asked whether a radio was required was because i found this:

 

Interconnecting Box, Gun Control / Audio Amplifier

NSN 5820-99-900-9552 was originally intended for remote audio control of line and radio in British Armoured Vehicles. Has 4 Remote Guns Control lines. Larkspur type connectors for audio and power. Audio Gain control, Radio or Line selector control. 24 Volt operation. Can be used with Larkspur Vehicle Radio equipment such as C-13, C-45, or as a stand alone vehicle intercom system.

 

Simple solution to a big problem, no need to buy a expensive radio system for your military vehicle just to add intercom facilities between the driver and commander. The system can work with or without a radio system. Duplex voice communications is possible. Can interface to Larkspur Vehicle Radio equipment such as C-13, C-45. Works on 24 VDC.

 

Interconnecting box, gun control. This is part of the original Larkspur generation vehicle harness typically used in the FV432 command vehicle of a FV433 Abbot SPG troop.

 

 

 

In relation to the IBRA i found this:

 

Interconnecting Box Radio Adapter (IBRA)

The interconnecting Box Radio Adapter enables Clansman Radios to be used to their full potential in a Larkspur harness, and provides the Intercom Amplifier for the Larkspur Harness.

 

Can the IBRA be used to add Larkspur equipment to a Clansman set up?

 

if using a IBRA in a larkspur harness with a Clansman radio does this negate the need for a Larkspur radio to enable the intercom function to work?

 

As the IBRA provides the Intercom Amplifier for the Larkspur Harness, does this negate the need for a radio?

 

 

In relation to different mic's and headsets for crew/commander i found this:

 

Microphone; Differences from the crew mic's are the selector switch on the microphone, gain control on the personal unit and the 12 pin plug (it's more or less a mic with a C box built-in).

 

Headset: Amplivox headset (which double as ear defenders) or the basic headset.

 

 

Sorry for all the questions.

 

Thanks

 

Tyler

[andym]

I can't say definitively but I'm pretty sure that an IBRA allows you to use a Larkspur intercom without a radio fitted. As the Clansman radios don't provide intercom that would seem logical. It was installed in the Abbot for just that purpose and I think there are Abbot owners using the intercom without a working Clansman radio. Unfortunately my Abbot isn't yet at a sufficiently advanced stage to confirm.

 

Andy

[tyler]

Hi Andy, thanks for that info.

Hopefully some one can confirm what you said so as to help both of us as I should think that with a beast like the Abbot you'll definitely be wanting a extra pair of eyes up in the turret.

[ferrettkitt]

IBRA can be difficult to get hold off if you're lucky enough to have one keep hold of it. I think I have only seen one or two on ebay in the last couple of years.

[ChasSomT.]

Not much use, I know, because I don't know what we Are using, but we have the 'Gold faced' Noise limiting(?) boxes on our 439, (a Clansman fitted vehicle) Clansman harnesses, but no Clansman - no radios at all, in fact.

 

'Chas.'

[fv1609]

Tyler I'm not sure if you are after a Larkspur intercom per se or whether you want it to complete the restoration.

 

But surely the intercom is in the diecast box (with volume control) mounted above the Larkspur junction box? I think the junction box is merely to interface the headsets to the diecast box rather there being any more Larkspur equipment fitted.

 

[Chris Suslowicz]

Actually I forget. In the absence of a working I/C circuit, there was, for Scorpion, an Emergency Crew Control, a separate handset that allowed the commander to talk to the driver. It was battleship grey and looked like something out of 1950s TV football commentary or, as I put it, a grey toffee apple.

 

That's the "Double button carbon microphone" or Tannoy microphone whch pre-dates the Scorpion (and possibly WW2).

 

The Emergency Crew Control microphone is identical to the "Apparatus Loudspeaking" used to control 25 pdr gun batteries: a big die-cast microphone with a 3-pin connector on the end of the cable. The same microphone was used in the early WW2 AFVs for driver intercom (as a limited number of slip-rings in the turret junction box only left two spare lines, for intercom (speech) and buzzer (signal)). Once later tanks had more connections between turret and hull, they switched to using standard headsets (with different Junction, Distribution control boxes) but retained the ECC microphone for the commander to use if the intercom amplifier failed.

[tyler]

Tyler I'm not sure if you are after a Larkspur intercom per se or whether you want it to complete the restoration.

 

Hi Clive, I am trying to complete the restoration to original as possible whilst working on the basis that there was intercom between the crew be that between all three or just 2 of them as your said a while ago. along with the Pye Westminster as comms/radio to what ever other units.

 

And as i have absolutely no knowledge of intercom and radio equipment at all, along with only basic info on the intercom and radio system used in the Shorland's being available (all of which you have kindly provided).

 

So i am trying to find out:

what original intercom equipment/set-up was used in the Shorland

if the original equipment is not available then how do i get as close to the original intercom equipment/set up (eg using a Larkspur intercom system (and as much of the current equipment as possible) as this would be closer to the original set up compared to fitting a Clansman set up.

 

So it is making it hard to figure out how to reinstate the intercom system and what equipment etc I need to do this reinstatement

 

So baring this in mind I am essentially trying to reinstate the original communication function between the crew of the Shorland. Because i will be driving it to shows not trailering it, i would prefer someone up in the turret keeping an eye out for other drivers etc and being able to relay info in this regard back to the driver rather than yell to communicate etc.

 

But surely the intercom is in the diecast box (with volume control) mounted above the Larkspur junction box? *I think the junction box is merely to interface the headsets to the diecast box rather there being any more Larkspur equipment fitted.

 

 

Clive as I know nothing of Radios etc this didnt cross my mind, but its a good point as why would they leave these 2 boxes in and take others that had possibly been fitted.

So does anyone know if the intercom would work with just:an Amplifier, 12v battery, headsets and Adapter unit 'A' box?

 

It turns out the Larkspur box that is fitted to Clive's Shorland (as per his pic) and my Shorland isn't a Interconnection Box LT 4-way No. 4 but rather a Adapter unit 'A' box, it was the little A on the box as seen in Clive's pic that gave it away, so I went and cleaned my box and also found an A on it.

 

Adapter unit 'A' box:

Adapter Unit Reception Set 'A' enables Reception Set R210 to be operated as a single receiver without Transmitter Radio C11. Connections are provided for two headsets, 24V supply and 12-pt lead to the receiver. A later version of this unit has a 'Phones out' insulated screw terminal fitted on top. Adapter Unit Headset 'T' may be used to connect additional headsets.

 

 

I found out that the commanders headset has a 12 pin plug the crewman's headset has a 6 pin plug along with the previously mentioned differences in that the commanders has the selector switch on the microphone and gain control on the personal unit.

 

 

So do you need the (IBRA) Interconnecting Box Radio Adaptor not the (IBHA) Interconnecting Box Harness Adaptor when fitting Clansman into Larkspur?

 

Thanks

[fv1609]

if the original equipment is not available then how do i get as close to the original intercom equipment/set up (eg using a Larkspur intercom system (and as much of the current equipment as possible) as this would be closer to the original set up compared to fitting a Clansman set up.

 

Tyler I don't think there is any need to look for a Larkspur intercom. I think if you take the lid off the diecast box you will find the intercom amplifier is in there. So you just need to look for headsets etc

 

The picture I posted was the set up I saw in several dozen Shorlands 25 years ago. I never had the chance to take the lid off, mine doesn't have any evidence of that set up as it was of an earlier time.

[tyler]

Here are some pics of the contents of the unknown box.

 

Anyone able to ID the purpose of the box? E.g f it is a amplifier?

Thanks

[fv1609]

Anyone able to ID the purpose of the box? E.g f it is a amplifier?

 

Yes as I have said that is your AF amplifier.

 

I think you will find it is the audio board from a Pye Westminster. I have the manuals somewhere.

[tyler]

Hi Clive, thought it was after you had first mentioned it, but just thought i'd make sure.

P's i still interested in that Fm Pye Westminster with mount if its still available.

I also have a 6 pin headset coming so should be able to test the system once it arrives.

 

Thanks.

[fv1609]

Tyler I think I have a pristine 4-way Larkspur junction box going back to the time when I thought I might construct the installation. I also may have some Eddystone diecast boxes if you wanted to transplant the guts into a new box.

[tyler]

Hi Clive, i think you sent me pics of the Larkspur No4 box when you sent pics of the Westies and spot light.

I may well be interested in the both the Larkspur and Eddy boxes.

 

Thanks.

[andym]

What's with the very RF-looking piece of co-ax coming from the connector on the right-hand side?

 

Andy

[barrynevuk]

Several years ago when I had my ferret, it had Larkspur boxes in which I wanted to keep. I found that there is an "I box" which can be used, which then allows use of the Larkspur harness/boxes without a radio.

For some info try this

 

http://wftw.nl/harnessb/harness.html

[fv1609]

Tyler here is the circuit diagram & component layout of your amplifier from a Westminster. It looks to be from a W15AM & rated at 2.5 watts of audio output. The board from the W15FM is very similar although that is rated at 2 watts. I have the component lists if needed.