The Beginning,
The Tornado ECR is a modified IDS produced by Germany as a replacement for the Phantom RF-4E.  The ECR program was approved by the German parliament in May 1986 with authorisation to build following on 10th June 1986. Delivery was to be between 1990 and 1992 with the airframes from batch 7.
Thirty five airframes were built although the original proposal was for forty. Two new squadrons were formed to operate the new aircraft. These being 2/JBG 38 at Jever and 3/JBG32 at Lechfeld.

 98-03 first flew in ECR configuration on 18/08/88.

It should be noted that Italy have produced some ECR airframes although the mission equipment is different to that of the German airframes.

ECR - IDS the Difference,
The basic airframe of the ECR is identical to the IDS, most of the changes were internal to the airframe.  On board computing power was upped to 128Kb of memory as per the ADV.  A 1553 databus was installed along with a 1760 weapons databus. A number of other subsystems that made up the counter measure systems are described below. Like the GR.1A the ECR carries no cannon.  An uprated version of the RB199 power plant were also installed, designated the RB199-34R-105.

ELS - Emitter Locator System
Produced by Texas Instruments, the emitter locator system is used to determine the type and location of any radar transmitter that illuminates the aircraft.  Information from this system is available to both crew members and is used to provide release data for the HARM (High Speed Anti Radiation Missile) missiles.

The data produced can be overlaid onto the aircrafts projected track thereby allowing a fuller mission picture and a real time threat evaluation.

The ELS main computer is based around six MIL-STD-1750A computers.

FLIR - Forward Looking Infra Red
The FLIR system, developed by Honeywell provides a horizon to horizon thermal picture.  The system utilises an Infra Red emitter/receiver  located under the cockpit floor as per the GR.1A.  The data produced by this system can be displayed to the crew along with overlaid mission data as per the ELS. A Carl Zeiss FLIR is also mounted in blister under the forward fuselage, this is a steerable unit and can be rotated through 180º.  Images from this source can be provide to both crew members.

ODIN
ODIN is a system that enables the Tornado ECR to forward and receive information in real time from other ODIN equipped sources.  It can be utilised for air to air and air to ground data transfers. 

HARM
The ECR's main weapon is the Texas Instruments AGM-88 high speed anti radiation missile.

Prototypes
The two German prototypes were 98-03/PS-16 and 45+75/4275

Production
The following German thirty five airframes were produced to ECR specification, these were  817, 818, 821, 823, 827, 830, 833, 837, 839, 842, 844, 847, 848, 851, 854, 856, 858, 860, 864, 866, 869, 871, 873, 876, 879, 881, 884, 887, 890, 894, 896, 898, 900, 903, 906.

Sixteen Italian IDS airframes were converted to their equivalent ECR specification, I am aware of the following airframes, 213,225,231,328,386,392,399,430,436,492,531,544,597,615, If you have details of the missing airframes please let me know.