No. 19 set CONSULTING WANTED - installation of No 19 set in Staghound Armoured Car

[Chris Suslowicz]

Hi Dan,

1) Driver + Bow Gunner are connecting to Junction Distribution No.1 or No.3 box with the "Call Commander" push button on it. This is intercom only, and which one is fitted depends on the number of slip-rings available in the rotary base junction to the turret. No.1 is the early type and just has Speech & Signal available, so gets +12V and Ground from the vehicle electrics and requires the "Tannoy" power microphone version of the headset (the grey lollypop). Later vehicles had more slip-rings available and used J.D.3 which fed Mic+ and Mic- through the junction and allowed the standard (black bakelite) Microphone and Headgear to be used.

2) The Gunner is actually the Wireless Operator/Gunner and has Control Unit No.2 with a red light on it and two switches: set selector (A, IC, B) and rebroadcast (Normal / Rebroadcast). The red light indicates "A set unattended" and will come on if none of the headsets are switched to the 'A' set. The 12-pin connectors are a pass-through, one will go to the WS19 and the other will go to the commander's control unit (No.1 or 1A, probably.)
Cable from radio usually goes into the connector on the side of CU2 and the cable between CU2 and CU 1 (or 1A) into the top one on each box (I think).

3) Early cables (brown paxolin inserts) were supplied in sets for specific installations and were crimped and/or soldered in the required connector orientation. This proved to be a big mistake (from a production/logistics point of view) and later cables (black bakelite inserts) could be changed in the field when the radio was being installed. If you have the later cables and remove the spring clip around the cable entry, the back cover can be lifted, unlocking the rear part of the shell. You can then (carefully, as the cable may be fragile after 80 years) rotate the rear portion to the desired position, lock it in place with the back cover, and re-fit the spring clip.

4) Is the Driver/Bow Gunner box a Junction Distribution No.1 or a No.3?

5) is the Commander/Loader box in the turret a Control Unit No.1 (or 1A) or a Junction Distribution No.1 or No.3? I think it should be a C.U.1 (or 1A).

6) a - maybe. It depends on the number of slip-rings in the rotary base junction. Early AFVs required the use of J.D.1 and 2 because there were only 2 spare circuits, later ones used J.D.3 and 4 with standard headsets. The early type had a 6-way cable from the WS19 Supply Unit to the turret junction box to allow for 2 x 12V feeds (split 24 volt vehicle power), SPEECH and SIGNAL. The later version used a cable from Control Unit No.1 to get the SPEECH, SIGNAL, Mic+ and Mic- into the lower hull (and used the IC Amplifier and standard headsets instead of +12V and Power Microphones).
The M4 Sherman wiring diagram shows both options (I think), which is confusing to the unwary.

b - later cables can be re-polarised to suit the intended application.

c - Argh! It's 01:37 and I have work tomorrow...

Good Morning!

Chris.

[daninnm]

CHRIS: many many thanks for that tutorial!!!!
I may have another question or two but you have cleared up a few things for me....I have some spare cabling so that is the issue.... I think that the long 12-pin plug to 12-pin plug cable actually needs another box than the early No1 box on gunner commander side of turret I am using. My commutator has two terminals below and five above...later model I think. I will look into that - I may have the wrong box over there.
the comments about reversing the lug is well taken - I will try that tomorrow to solve the cabling run problem we are having because of the radio tray sticking out past the end of the socket....shot of turret interior psoted

[maple_leaf_eh]

I knew very little about wartime radio installations at the beginning of the conversation, and now I am just a little smarter for it!

[Chris Suslowicz]

Originally Posted by daninnm

CHRIS: many many thanks for that tutorial!!!!
I may have another question or two but you have cleared up a few things for me....I have some spare cabling so that is the issue.... I think that the long 12-pin plug to 12-pin plug cable actually needs another box than the early No1 box on gunner commander side of turret I am using. My commutator has two terminals below and five above...later model I think. I will look into that - I may have the wrong box over there.
the comments about reversing the lug is well taken - I will try that tomorrow to solve the cabling run problem we are having because of the radio tray sticking out past the end of the socket....shot of turret interior psoted

No sign of an image, but I did a bit of "research" last night... lots of photos od the T17E1 but they're either exterior shots or there's no radio kit fitted.

At one point I got sidetracked into the Marmon-Herrington, which only has a crew of three (so could get away with a single control box for the commander and a junction distribution for the driver and bow gunner), but the T17E1 has a crew of 5 so will be more like a Sherman, and I suspect those drawings will be a good match. It's also late enough to use JD3 for the intercom box in the hull and the same headset assemblies throughout.

Need some interior photos of crew and radio positions - if it's two in the turret (commander & gunner) and three in the hull (driver, bow gunner, loader), then it might just use a single control unit No.1 for commander and gunner, and junction distributions 3 & 4 for everyone "down below". If not, maybe Control Units 1 (Commander & Gunner) and 2 (Wireless operator) and a J.D.3 in the hull for Driver and Bow Gunner. The Junction Distribution boxes would be fed from Control Unit No.1 via the turret and hull junction boxes.
(Because you need both microphone leads plus the "Signal" line and those won't fit in the 6-way power connector.)

Maybe I should write this up neatly, with diagrams?

Chris.

[daninnm]

I will take some photos tomorrow and explain what my setup is. Hopefully I have done it right!!!!!
In the T17E1 Staghound there are two crew in the hull: driver and bow gunner. Their comm box is a No.1 between them with the Commander Call Button and two drop cords.
The commutator in the Staghound is an 8-ring set (later variety) – six comm rings and two power rings below for the 12v and 24 power cables. 24 volts runs the turret drive motor that the gunner sits on, and the 12 volts goes to the radio.
There are three crew in the turret basket (and, yes, Virginia, it is very crowded with late 20th century guys in there).
So, there is a Comm box with ten terminals below the radio tray. That Comm box is shown on the RAM TANK diagram on the No. 19 set website. I will make my connections in that box according to the diagram.
In that comm box…. the cable from the driver / bow gunner position comes up in a conduit from the commutator…. Mic+ Mic- Speech Signal and 12+ and 12- I have those leads marked from looking in the No.1 box and tracing which leads had continuity.
On right side of the turret is the Gunner, he sits alone and has a box that has TWO 12-pin sockets and a cable that has the mic+ mic-, speech, signal, and 12+ and 12- ending in wires with terminal lugs. I intend to connect those in the Comm Box under the radio. I ran a 12-pin to 12-pin cable between the lower left corner of the No. 19 set (moving the socket around as you suggested to realign the pin to let the plug and cable enter the No. 19 set socket from the left side (crossing in front of the power supply). The small dog-bone connects the power supply to the radio at the top.
This is where I differ and hope my set up is right. On the left side of the turret sits the commander and the loader. I put a box there that has the A-B switch and two drop cords and a Single 12-pin socket and a single cable terminating in 6 wires into an Appleton (mic+ mic-, speech, signal, and 12+ and 12-). I will connect the Appleton protruding wires into the Comm Box in the mic+ mic- speech, signal 12+ and 12- terminals. I will run a 12-pin to 12-pin cable from the second 12-pin socket on right-side gunner’s radio box to the single 12-pin socket on the commanders’ left side box.
Essentially the two radio control boxes (one left and one right side of the turret (basket) are connected together with the 12-pin Plugs to the No. 19 set. The power cables (think ones without the 12-pin plugs) go into the Comm box below the radio and connect to the commutator power and the single Commander Call box in driver (driver/bow gunner) compartment.
Do I need to remove the fuse in the upper portion of the No.1 boxes in either side of the turret?
I will do a block diagram tomorrow and attach photos…. Been a ham radio op for 50+ years but this setup has puzzled me until I studied the book and looked at all the boxes and connectors, I had…...K4RN/5
Comments appreciated even if you think I dun it wrong!!!!!!!!!!!!

[David Dunlop]

Dan.

In the turret, is the Gunner not located lower left, below the Commander, where the optical sights, turret controls and trigger are located? The upper right position would be the Loader/Operator in charge of Wireless, Loading, Coaxial MG and Roof Top Flare Pistol?

David

[Chris Suslowicz]

I think I've worked out what's wrong, and the various boxes are in the wrong place. (David's post and the photograph of the J.D.3 between the Binoculars and Signal cartridges also helped.)

Assuming that's "upstairs", i.e. in the turret, it's definitely in the wrong place, because that's for the Driver and Bow Gunner down in the hull. The cable from the JD3 connects to the Hull Junction Box for access to the Rotary Base Junction. Connections are Speech (Intercom output), Signal (buzzer call to commander's droplead), Mic+ & Mic- (for intercom), 12V (for buzzer) and earth (for buzzer and intercom ground).

Because it's currently located between the Binoculars and Signal Cartridges, I'd guess that's the Commander's position, and should have Control Unit No.1 (which has a single 12-way connector, two dropleads (commander and gunner) and a switch that can select A IC B. It will also have a cable entry for a 4-way lead that connects the turret junction box to the terminal board in the control unit: Signal, Speech, Mic+ & Mic- (the cable entry can come out of the top of the box, next to the 12-way connector, or from the right hand side - unused holes will be blocked by rubber grommets). A 12-way cable runs from the connector on the top of the box, round the back wall of the turret to the Radio Operator's Box (Control Unit No.2) which has a single droplead, two switches (A IC B and N R), a red warning light ("A Set Unattended") and two 12-way connectors.One of the 12-way connectors goes to Control Unit No.1, the other goes to the Wireless Set.

Power supply: the cable used depends on the vehicle voltage (the WS19 itself requires 12 volts) and the power unit fitted. It's a late-WW2 vehicle, so has a 24 Volt battery (probably) and Wireless Set No.19 Mk.3 (probably Canadian, with Supply Unit No.2). That can have 3 options: 12V 2-wire feed, 24-volt 3-wire feed or 24 volt 2-wire feed, and they require different connections to the turret terminal box. Getting it wrong can cause serious damage to the set - like "all the valves and lamps will have to be replaced" damage.

What set and supply unit do you have?

Best regards,
Chris.

[David Dunlop]

Dan.

In Post #6 you mention a wireless connector hitting the radio tray so not fitting properly. Can you post a photo of that problem? The floor of the wireless bustle at the back of the turret should have locations on it for the four shock mounts of the Carriers No 21 to be fastened. Once they are in place, the Carriers No. 21 can be fastened to them and this arrangement is intended to allow all cables to properly clear.


David