Radio set No 11 power supply leads.

[Chris Suslowicz]

Originally Posted by universalgrl

Any chance of getting the power plug and socket made for my 38 AFV set. Some one hardwired a cable inside the radio and took out the socket. I think the plug is identical to the WS19HP 12 V plug but about half the size.

It's rather smaller than that. It's the one used for the "Control" lead on the WS19HP amplifier (where it's connected to the relay coil and is in series with the WS19 HT2). The same connector is an even more "multi purpose part" and was used on the WS 38, 31 and 88 AFV supply units, the R109 and supply units for the WS22 and PCR series receivers.

The large one is ZA.6403 (and I've just discovered my spare one is a shorting link, which explains its use in the Larkspur test boxes: presumably there's a lead for use with a DC ammeter that replaces it so you can measure the set input current via that plug/socket and the applied voltage via a pair of banana sockets on the test box. This probably means I ought to get more of them when I find some!)

The small one has ZA.32806 on it, which makes it well post-WW2 and probably for the WS31 or WS88 AFV supply unit/LF amplifier. They appear to have had a thing about renumbering things after WW2. There _will_ be earlier examples with a lower number.

Chris.

[kevin powles]

Gents, I have just had some of the 2 pin plugs made, I will post up some pics in the next few days, these have a pigment mixed in with the moulded plastic to match the Bakelite 'blackness' exactly.

Let me know if you need any, I have one set aside for Phil, Gina you need one now?.

Chris which radio do these also fit as others might want them.

I will machine drill the pin holes and tap the lid screw holes, you will have to add the lid gasket and brass inserts, these cant be added at the manufacture stage as the alignment is critical, weather they were moulded in originally I'm not sure.

Kevin.

[Mrs Vampire]

yep book me down for one

[kevin powles]

Gents, the 2 pin plugs are ready. I will pm details to both people who wanted one each.

[Mrs Vampire]

Fantastic

[kevin powles]

Starting making the tray after getting some very fine drawing from another MLU'er, I managed to locate the correct size extruded aluminium as per the originals, these cross sections are finished apart from a couple of holes and riveted on top thread fittings, will make the end plates next week.

Kevin.

[kevin powles]

I have finished a set of plugs for the 11 set, all brass inserts in place.

I have a set still available still if anyone ones a set without the brass work.

Many thanks to those who made the plug copying possible.

Kevin.

[kevin powles]

Gents, Mostly finished the Canadian pattern Aluminum tray, just got to put a couple of mystery holes in and get dimensions for the top mounted tray if anyone has dimensions from an original. Also there is another item that sits on top to make a small mount for.

Kevin.

[kevin powles]

I have to put some wrinkle finish on it, any one recommend a suitable aerosol brand?.

Kevin.

[Mrs Vampire]

Been a while since I used any Kevin but most work better if the object to be painted is warm.
Nice job ...do you have dwgs??

[kevin powles]

Originally Posted by Gina Vampire

Been a while since I used any Kevin but most work better if the object to be painted is warm.
Nice job ...do you have dwgs??

Hi Gina, I plan to paint it next week, I am waiting for material to arrive to make the top tray, I plan to turn my blast cabinet into an oven to heat up before painting for best results, then of course a top coat to colour match to the 11 set radio.

Did your plug arrive ?, I have drawing of this Canadian version, but there is so much work involved in getting it right, if you are making it yourself no problem, but if you were paying someone to make it, it's uneconomical, must of put 40 hours in to get this far!.

Kevin.

[Mrs Vampire]

Kevin

Not arrived yet will let you know when it does. I would be making it myself...not rich enough to have someone else do it

Looks like it will be a cracker of a radio when its finished....

Its nice to deal with such friendly folk when it comes to N0 11 radios ;-)

[kevin powles]

Originally Posted by Gina Vampire

Kevin

Not arrived yet will let you know when it does. I would be making it myself...not rich enough to have someone else do it

Looks like it will be a cracker of a radio when its finished....

Its nice to deal with such friendly folk when it comes to N0 11 radios ;-)

Gina, I will photograph the plans and email them to you, but I understand the Australian version of the carrier frame is pressed steel and there are differences.

Kevin.

[Mike Kelly]

Originally Posted by kevin powles

I have to put some wrinkle finish on it, any one recommend a suitable aerosol brand?.

Kevin.

Very nice job........ interesting they used extruded alloy . The Aust. version is pressed steel channels

[kevin powles]

Originally Posted by Mike Kelly

Very nice job........ interesting they used extruded alloy . The Aust. version is pressed steel channels

Hi Mike, I think the Aluminium version is easier to make, less tooling required, you just have to source the correct 1/8" thick extruded channeling, here is a pic of the one it's copied from.

Kevin.

[Mrs Vampire]

Kevins plug turned up today.

I would challenge anyone to pick it from an original save for its brand new appearance. Many thanks for that Kevin and also for the very detailed drawings .

You are a champ no doubt about it !!!!

[kevin powles]

Originally Posted by Gina Vampire

Kevins plug turned up today.

I would challenge anyone to pick it from an original save for its brand new appearance. Many thanks for that Kevin and also for the very detailed drawings .

You are a champ no doubt about it !!!!

Thanks Gina, I haven't forgot about photographing the frame carrier drawing to send. Will do it this week.

Kevin.

[kevin powles]

Here is the 11 carrier ready for painting, one painted it only requires the padding and a couple of missing thackery washers.

Thanks to all those that made the project possible.

Gina, I have sent photos of the drawings.

Kevin.

[kevin powles]

Here is the set fitted.

[Mike Kelly]

Kevin

I see you have the large isolating capacitor on the frame itself - a very important item to have in a vehicle equipped with a mobile wireless set .

Case in point. During the 1950's floods in the Hunter Valley NSW , the army had a few DUKW's rescuing people . Sadly at least one or more of the signallers in a DUKW was electrocuted when the antenna of their wireless set hit a HV power line . Mike

[kevin powles]

Mike, Thanks for the warning, I note I am missing a knob off the 11 set, ANYONE GOT A SPARE?.

Kevin.

[Chris Suslowicz]

Originally Posted by Mike Kelly

Kevin

I see you have the large isolating capacitor on the frame itself - a very important item to have in a vehicle equipped with a mobile wireless set .

Case in point. During the 1950's floods in the Hunter Valley NSW , the army had a few DUKW's rescuing people . Sadly at least one or more of the signallers in a DUKW was electrocuted when the antenna of their wireless set hit a HV power line . Mike

Unfortunately that capacitor won't protect you against high voltage lines. It's there to protect the set (particularly the aerial current metering circuits) from low voltage overhead distribution lines (trams, trolley buses, and domestic feeders) that a whip aerial is likely to make contact with. It won't protect against the medium voltage (11kV or 33kV used in England, other countries may vary), since the capacitor is only rated at 5kV DC.

(The WS19 variometer has a similar capacitor built in, but the Aerial Tuning Inductance No.1 or Aerial Coupling Unit 'J' used with the RF amplifier (for WS19HP) do not, and are used with an external capacitor to protect the metering circuitry.)

[Chris Suslowicz]

Originally Posted by kevin powles

Mike, Thanks for the warning, I note I am missing a knob off the 11 set, ANYONE GOT A SPARE?.

Kevin.

If it's the cylindrical fluted type, then I probably have some as they were standard on the British WS19.

Chris.

[kevin powles]

Originally Posted by Chris Suslowicz

If it's the cylindrical fluted type, then I probably have some as they were standard on the British WS19.

Chris.

Chris, I think it's the same as the knob the other side of the handle in the picture attached, would gladly swap it.

Kevin.

[Mike Kelly]

Originally Posted by Chris Suslowicz

since the capacitor is only rated at 5kV DC.

.)

In that case, at least, the capacitor in question will protect the set and its operators I suggest , against the common 240V power lines , these domestic lines are far more common in a city /suburban environment . The kV lines are usually seen in rural areas, and are normally suspended at higher heights , unlikely to hit a whip antenna . Mike

[Mike Kelly]

Originally Posted by Chris Suslowicz

Unfortunately that capacitor won't protect you against high voltage lines. .)

I disagree . 240 volt domestic power lines are lethal and dangerous . Mike

[Mrs Vampire]

Lovely Job Kevin ...absolutely fantastic attention to detail. Many thanks for the drawings.

So far as antenna touching overheads I guess the best advice is dont!! Not sure a big capacitor being an AC low impedance device would offer much by way of insurance.

i wonders to meself then *scratching chin* how many electrocutions, arks and sparks , fires and so on were caused by that significant detail. Do we have a spark gap somwheres in the system?? Would the Co Ax frizzle up??

Just thinking about the path back to the power o/p stage ....

I would be interested to know.

[Mike Kelly]

Originally Posted by Gina Vampire

So far as antenna touching overheads I guess the best advice is dont!! Not sure a big capacitor being an AC low impedance device would offer much by way of insurance.



.

Yes because of the small microfarad value of that capacitor , the reactance and impedance would be relatively low at 50 hertz . From memory the reactance lowers as the freq. is increased , the opposite to inductance where the reactance increases with freq.

[Chris Suslowicz]

Originally Posted by Mike Kelly

I disagree . 240 volt domestic power lines are lethal and dangerous . Mike

I won't disagree with you on that statement, but I was using the power distribution definition of "Low Voltage".

(From Wonkypedia, so likely to be U.S. biased)

Overhead power transmission lines are classified in the electrical power industry by the range of voltages:

Low voltage (LV) – less than 1000 volts, used for connection between a residential or small commercial customer and the utility.
Medium voltage (MV; distribution) – between 1000 volts (1 kV) and to 69 kV, used for distribution in urban and rural areas.
High voltage (HV; subtransmission less than 100 kV; subtransmission or transmission at voltage such as 115 kV and 138 kV), used for sub-transmission and transmission of bulk quantities of electric power and connection to very large consumers.
Extra high voltage (EHV; transmission) – over 230 kV, up to about 800 kV, used for long distance, very high power transmission.
Ultra high voltage (UHV) – higher than 800 kV

Low Voltage in the U.K. was the overhead poled supply running alongside residential roads, with four parallel wires supported on insulators. This was a 3-phase Y connected supply (240/250 volts phase to neutral, 415/440 volts phase to phase) and houses were connected to each phase in turn while commercial buildings requiring more power could have a 3-phase feed (farms, garages, etc.).

Medium Voltage is 11 or 33 kV, again on overhead poles (rather taller, and usually with the wires horizontally spaced on a crossarm) and Delta connected to remove the need for a neutral connection.

High Voltage is on the very tall steel pylons. (Usually 132 kV and above, for long distance transmission.)

Chris.

[Mrs Vampire]

Mike XC =1/2pi FC

C is capacitance F is frequency XC is capacitive reactance