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Control Head Modifications
Equipment needed to perform this modification.
UV Eprom Eraser
Eprom Burner (Programmer)
S950 /S990 Modification Files, Available on the Delta Page on this website under radio mods.
The first thing you need to do is disassemble the control head to remove the Firmware Eprom and the Codeplug EEprom from their sockets.
Once you have the chips removed I suggest you read the Firmware Eprom and the codeplug EEprom and save these images as backups in case you ever need to revert back to the stock configuration.
Then the firmware Eprom needs to have its label removed, then clean the window with a suitable solvent to remove the sticker residue and clear the window. Once this is done place it in your UV eraser for the appropriate amount of time, consult your eraser for this info, and get it blanked! Once its blank, as verified by your Eprom burner, load the S990prog.rom file into your burner software and program. The firmware chip is now ready to be re-labeled and replaced.
The EEprom is your standard electrical erasable prom, so just put it in your Eprom burner and load the appropriate file and reprogram.
8 Mode 16 Frequency radios use the 8mode16f.bin file.
4 Mode 32 Frequency radios use the 4mode32f.bin file.
To make the frequency changes as described later on this page write to the head's internal EEprom, a programming jumper must be in place. This jumper goes between pins 3 and 4 on the rear of the unit where the GE 'suitcase' programmer would normally connect. For quick and easy changes on the road it would do you well to add a small switch in the head between these pins:
This makes it much easier to change a channel frequency 'on the fly'
Here is a step by step with pictures showing how to program in frequencies once you have modified the control head with the firmware and codeplug files available on the Delta page on my website and as described above.
With the radio turned off flip the programming switch to Program or install a jumper across pins 3 and 4 of the suitcase programming connector, 3 and 4 are the center two pins. If your not installing a switch just use a push on PCB jumper as used in computers, it fits the pins just right on the ones I have tested.
Push and hold the ADD and DEL buttons and then turn it on.
The first one shows what you will get when you power up the unit with the 'ADD' and 'DELETE' buttons pressed. This lets you select in which MODE to change data. For you Motorola guys like me, Mode is the same as Banks or Zones for GE, not the individual channels as Motorola calls them Modes. The MODE up and down buttons are used:
Once the MODE is selected, tap the "*" key, on some radios this may be labeled differently, mine had an EMEG label on this button. This will now move you to the CHANNEL window to select which channel you will modify. The channel up and down buttons are used:
Again tap the "*" key. This gets you to the transmit frequency, the TX light will be on to indicate this, but the radio is not transmitting so don't worry! Use the mode, channel and scan keys to change the data:
Again tap the "*" key. The next step is for entering the transmit CG (PL) tone that is entered from the table. When in the programming mode and scrolling through the settings for a channel, the CG tone code is always set to 00, even if a different value was previously programmed. This also happens if you just set a value other than 00 and you are reviewing the channel again. So don't worry, if you set the tone its there, but reviewing the channel data will show 00. Probably a good idea to print out the chart and keep it handy:
|00 = PL Disable, CSQ Only||18 = 123.0|
|01 = 67.0||19 = 127.3|
|02 = 71.9||20 = 131.8|
|03 = 74.4||21 = 136.5|
|04 = 77.0||22 = 141.3|
|05 = 79.7||23 = 146.2|
|06 = 82.5||24 = 151.4|
|07 = 85.4||25 = 156.7|
|08 = 88.5||26 = 162.2|
|09 = 91.5||27 = 167.9|
|10 = 94.8||28 = 173.8|
|11 = 97.4||29 = 179.9|
|12 = 100.0||30 = 186.2|
|13 = 103.5||31 = 192.8|
|14 = 107.2||32 = 203.5|
|15 = 110.9||33 = 210.7|
|16 = 114.8|
|17 = 118.8|
Again tap the "*" key. The next step will be for the receive frequency and the busy light will be on, and again you will use the MODE, CHANNEL and SCAN keys to change the data:
The next step is for the receive CG tone that is entered from the table.
Refer to the table and info above for the TX programming as its the same
Once all the changes are made tap the squelch (SQ) down key to write the data and reset, it will reset and return to normal operation. Set the switch back to normal operation or remove your temporary jumper now and your done.
I found this info on the web a while back and misplaced the link to the website which contained it and cannot find it via Google search or other methods. So I recreated it from a saved .pdf copy I had created of the website for all to refer to as it was becoming tiresome to continuously email the .pdf file around.
The best I can find for proof of the creator of this modification was on the original website and in the text files included with the original files for modifying the proms in the head. So I will therefore give credit to that person here and if I am giving undue credit to anyone please let me know! I haven't been able to make contact with anyone to confirm. It is not my intent to take credit for this, because I certainly didn't figure this all out myself!
Thanks go out to:
David - WD4JKH
For making these radios useful once again!
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This site was last updated 01/25/10