zaterdag 4 maart 2017

Program the Racal Cougar - Part 7

This week i added support for the PRM 4515 H (132-174) models to the Arduino Racal Cougar Programmer.

PRM 4515 H

I received a package from the UK containing a PRM 4515 H model from a fellow OM for me to use to test the programmer for this particular model. (Thanks Dave !)

After making some changes to the frequency logic in the programmer code, mainly add support for the 100 Mz digit which was hard coded to '0', the programmer was able to program this model also.

Model selection:

When the Cougar is turned on it sends a 52 bit datastream, 7E 0D 7E 0D 60 4C 4, which i thought was some kind of model identification used by peripheral devices. This could be useful for the programmer to automatically select the right model and frequency bounds supported by the model.

The fist thing i did after receiving the H model was slide it in a S.M.T. and hook it up to an Arduino using the tap cable between the S.M.T and E.C.U and turn it on to register this data datastream and the result was a bit disappointing: the same datastream as the L model was send by this model. This means it's not possible to automatically identify the model connected to the programmer so this has to be done manually.

Main menu with model selection option.

To select the model connected to the programmer i added the 'm' (lower case M) menu option which brings up the model selection sub menu:

Model selection sub menu
Model selection is needed to define the lower and upper bounds of the programmable frequencies, use the correct Eeprom stored frequencies and determine if the model supports disabling the transmitted 150 hz pilot tone.

By default the programmer starts up with the L model selected, this can be changed in the Arduino sketch by changing the following line:

uint8_t selectedModel = MODEL_L;

uint8_t selectedModel = MODEL_H;

H model frequencies

The PRM 4515 H model operates from 132 to 174 Mhz in 20 Mhz bands. Which band it operates on is defined by the model number:

ModelBand startBand end
H3TAU132 Mhz151.9875 Mhz
H3TBU134 Mhz153.9875 Mhz
H3TCU136 Mhz155.9875 Mhz
H3TDU138 Mhz157.9875 Mhz
H3TEU140 Mhz159.9875 Mhz
H3TFU142 Mhz161.9875 Mhz
H3TGU144 Mhz163.9875 Mhz
H3THU146 Mhz165.9875 Mhz
H3TIU148 Mhz167.9875 Mhz
H3TJU150 Mz169.9875 Mhz
H3TKU152 Mhz171.9875 Mhz
H3TLU154 Mhz173.9875 Mhz

This band can be changed by changing some resistor jumpers as described on the site.

It is important to know the band your H model is operating on before using the Arduino Racal Cougar programmer. Trying to program a frequency outside your model its band will result in a program error.

150 hz pilot tone

The PRM 4515 H model doesn't support disabling of the 150 hz pilot tone using the programmer. This setting will be ignored when programming the H model.

Arduino Sketch

The new version, lets call it v0.0.3 to illustrate this is experimental software, can be downloaded using this link.

Update 15-10-2015: A new version v0.0.4 is available that fixes the default channel data being garbage when a fresh Arduino was used and channel data hasn't been stored before. Download this version using this link

See my previous post on the Arduino hardware used and installation instructions.


3 opmerkingen:

  1. hi dave,
    i have followed this for a long time, do you intend
    to publish the sketch to program the crypto codes into the cougar, best regards mick

  2. Hello Dave,

    Many thanks indeed for your excellent work on this project. I would also like to experiment with the crypto modules in my radio, if you were able to release a sketch file to program the key codes.

    Best Regards


    1. Hi Peter,

      The sketch isn't ready to be published yet but i can send you the schematics and the binary (hex) version of the programmer code which you can load in your Arduino.

      If you send me an email message with your call sign i will email it to you.

      my address is [my-call-sign] where [my-call-sign] is my callsign pa5dof.