SP8WJT/HF8V			  			   - RED ARMY RADIOTELEGRAPH SIMULATOR -						 SP8WJT/HF8V




									============					
									KRIEGSMARINE
									============					

									 ver. 4 29	
										





	01. UBOOTS 




OVERVIEW:

	German U-boats maintained contact with and received orders from their home bases by high frequency radio communications, but to insure that U-boats 
	received all traffic, and elaborate very low frequency repetition service was in operation over which practically all U-boat traffic was repeated.
	The control stations on the U-boat circuits delivered traffic to U-boats by either the "Broadcast" or "Intercept" method. The same H/F circuits 
	were used for both shore-ship and ship-shore traffic. The control stations observed fixed silent periods on all circuits for the reception of U-boat
	transmissions. In addition to these fixed silent periods, the shore stations normally observed a five-second pause at the end of each fortieth group 
	in long transmission in order to permit U-boats with traffic of higher precedence to break in. Thus a U-boat could transmit during silent periods, 
	during the five-second pause, or at any time when control signified that the circuit was clear by use of "VA." Neither external address nor call sign 
	were used by U-boats. Control acknowledged a U-boat transmission by repeating the message and inserting a serial number in the heading.
	Source: [1]




	=============
	01. UBOOT NET
	=============

	This is well-known historical network, on historical frequencies.



CALLSIGNS: 	nil (see message formats)

TRAFFIC:	- Enigma Naval QTCs. 4L with 2 indicator groups.
		- SHORT SIGNALS CODE (KURZSIGNALHEFT) 
		- Weather Code 	


FREQS:

	438	Homing freq for 'Wolf Pacs'
	4000	Baltic  
	5650	Atlantic
	7647	Atlantic
	10525	Atlantic
	12215	Atlantic





SIMULATION:

	3 types of Naval Enigma messages are simulated, callsigns are encoded in text.
	Callsigns were used only in sub-sub QSOs (coordinations during Wolf Packs attacks, etc )
	On some frequncies also Courier bursts can be heard.




ENIGMA QTC FORMAT:	

		Enigma QTC procedure looks like this:

		HHMM/DD GR  AAAA BBBB FNAD XYZA .... AAAA BBBB +   

		H    - hour
		M    - minute
		DD   - day
		GR   - groups 
		AAAA - indicator group 1
		BBBB - indicator group 2		


		No BT signal is used between PBL and TXT

		

SHORT SIGNALS CODE (KURZSIGNALHEFT) FORMAT:	

		<BB><BB><BB> AAA QLTISCYKAZEETNFX OJ AAA ] 

		<BB> - SHORT SIGNALS CODE (KURZSIGNALHEFT)
		AAA  - enigma indicator

		QLTISCYKAZEETNFX - enigma encoded book text (4 groups)
		OJ   - uboot encooded callsign
 


WEATHER CODE (WETTERKURZSCHLUESSEL) FORMAT:	

		WWJKZNISFQEFLJ ]

		WW  - WEATHER CODE (WETTERKURZSCHLUESSEL)  
		J   - Key ID 
		KZN - Position  		
		I   - Pressure
		S   - air temperature
		F   - clouds
		Q   - visibility
		E   - wind (strenghth and direction)	 
		F   - sea state 
		LJ  - uboot encooded callsign




SOURCE:
	[1] https://www.ibiblio.org/hyperwar/ETO/Ultra/SRH-025/SRH025-8.html
	[2] https://www.codesandciphers.org.uk/documents/egenproc/eniggnix.htm
	[3] Enigma Bliżej Prawdy - Marek Grajek