[Milsurplus] 68, 22, 19, 18, Sets.

[Bob Camp]

Hi

You bring up an interesting possibility on the crystals *if* the radios 
had been in storage for a while. There is a well documented problem 
that occurred with the manufacture of crystals in mid WWII. The 
solution was well in place by mid 1944 so it did not occur to me that 
it might apply here.

Basically when they made the crystals the surface finish was not as 
good as it could have been The result was the crystals changed 
frequency or simply died after being in storage for a while. The 
problem had the Eighth Air Force grounded for a while. Needless to say 
it got some attention at a fairly high level once that happened. The 
solution was to introduce an etching step into the manufacturing 
process. We still do the same thing today ...

	Take Care!

		Bob Camp
		KB8TQ




On Nov 14, 2004, at 5:22 AM, Paul Galpin wrote:

>
> The facts are :
> 1. The 19 set is the 19 set that we all know - usually fixed in a 
> vehicle or
> at an operating position. Uses 807 in the final. Maybe with an HP unit 
> to
> boost the output. Used where 240 or 12V power is plentifully available.
>
> 2. The 22 set is a similar but different transceiver, fixed in a 
> vehicle or
> "portable", meaning one guy carries the 12V battery(ies), one the set 
> and
> one the rest of the accessories, but not really suitable for use on the
> move. Designed to be sparing on 12V power. Typically carried out to an
> artillery spotting position and operated from there, with one member
> trotting back occasionally to get newly charged batts. Same frequency 
> range
> as the 19, but lower power - uses 3x EL32 (VT52) in the final.
>
> 3. The 18 and 68 sets were only designed as portables, used 
> on-the-move.
> One operator and one carrier. There is no separate "battery version" 
> of the
> 18/68 - they are designed to run as frugally as possible from dry cells
> (120V and 3V). Of course the batteries can be replaced by a mains 
> supply,
> but AFAIK there was never an official one made, even the 
> workshop/training
> supply was a collection of larger batteries. All versions of the 18 
> and 68
> sets are basically the same circuitry, except that the 68 is a low 
> frequency
> version of the 18.
>
> Frequency ranges:
> WS19  	2-8MHz
> WS22  	2-8MHz
> WS18  	6-9MHz
> WS68R&T	3-5.2MHz
> WS68P		1.7-2.9MHz
>
> Much of this info comes from Louis Meultee's books - surely everyone 
> on this
> list should have the set?! If not, why not?
>
>
>
> As regards "Market Garden" the stories I have heard include wrong 
> crystals
> (68s and later 18s could take a crystal), and also sets netted in, but 
> then
> stored for a long time, and not re-netted before use. Yes, I can just
> visualise the poor operators being told "These sets have been tuned in 
> using
> very expensive equipment, and if I find any of you have been touching 
> that
> frequency knob, you'll be on a charge before you know what's 
> happened!!"
>
> Paul Galpin
> (ZR6ACV)
> Ex Royal Signals
>
>
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