Key Radio KME Series - Amateur Conversion Information

Key Radio KME 80 / 150 / 450 Series
Amateur Conversion Information

by Tom Grady G6IGA keyradioatsuperiorsignals.co.uk copyright 1998-2022

All registered trademarks are acknowledged

Key KME Radio

Starting to convert Key KME Radios

Before anything can be set up the first thing that must be configured is the 2764 eprom which holds the frequency information located in the middle of the circuit board

Key KME80 Service Manual in pdf format

Link to Key KME80 Service Manual in pdf format size 45 Megs 63 pages

Programming the frequencies into the 2764 eprom

PLEASE NOTE: I am not able to supply parts, only answer questions about KEY KME series radios ! (I'm always hunting for Key bits myself though)

Hopefully readers of this article will be familiar with how to actually program a 2764 eprom, the information below purely describes how to calculate the frequency information to go into the 2764.

Please contact epromsatsuperiorsignals.co.uk for pre-programmed devices @ GBP 11.45 UK pounds (inc GBP 1.45 UK postage) / 13.00 Euros each (inc GBP 4.25 international postage) (Please note as 2732 eproms are no longer manufactured, the devices MAY be recycled ones). 6.45 GBP UK pounds (inc GBP 1.45 UK postage) / 7.50 Euros (inc GBP 4.25 international postage) each if you supply the blank devices .

KME 80 / 150
The Maths !

In the KME the reference division ratio is defined at the start being either 12.5KHz or 10KHz and cannot be changed per frequency each of the 16 channels must be 12.5KHz or 10KHz steps.
A number of parameters need entered into the Eprom Starting at address 07C0;
The 12.8MHz TCXO is divided by either 1024 to provide a 12.5/25KHz Channel Spacing OR 1280 to provide 20/30KHz Channel Spacing.
12.8MHz/0.0125=1024 or 10000000000 in Binary (put into address 07C0-07CB see table below).
12.8MHz/0.0100=1280 or 10100000000 in Binary (put into address 07C0-07CB see table below).
07CC-07DF Fixed Data for CPU Programming (see table below)
07E0-07FF This area always set to Zero (see table below)
NT Division Ratio (either 1024 or 1280) 1024 = TX Frequency (example 70.4875MHz) / 0.0125 = 5639
To obtain N division ratio and A division ratio NT (5639) = 16 x N (352 x 16) + A (Remainder of 7)
N = Number of Complete Divisions of 16
A = Remainder of the Basic Division Rate
N = 352 or 1100000 in Binary added to channel 1 TX address 0807-0811
A = 7 or 0111 in Binary added to channel 1 TX address 0800-0803
0804-0806 always Zero
0812-081F Always Fixed Data as per table.
NT Division Ratio (either 1024 or 1280) 1024 = RX Frequency (example 70.4875MHz+20.8MHz IF (KME150-20.8MHz IF)) / 0.0125 = 7303
To Obtain N division ratio and A division ratio NT (7303) = 16 x N (456 x 16) + A (Remainder of 7)
N = Number of Complete Divisions of 16
A = Remainder of the Basic Division Rate
N = 456 or 111001000 in Binary added to channel 1 RX address 0827-0831
A = 7 or 0111 in Binary added to channel 1 RX address 0820-0823
0824-0826 Always Zero
0832-083F Always Fixed Data as per table.

Key KME80/150 2764 Eprom Coding
Starts at Address 07C0	07C0	07C1	07C2	07C3	07C4	07C5	07C6	07C7	07C8	07C9	07CA	07CB	07CC	07CD	07CE	07CF
Use of Address	N0(1)	N1(2)	N2(4)	N3(8)	N4(16)	N5(32)	N6(64)	N7(128)	N8(256)	N9(512)	N10(1024)	N11(2048)	Fixed for CPU	Fixed for CPU	Fixed for CPU	Fixed for CPU
1024 12.5/25KHz Channel Spacing (N0-N11)	0	0	0	0	0	0	0	0	0	0	1	0	0	0	0	1
1280 20/30KHz Channel Spacing (N0-N11)	0	0	0	0	0	0	0	0	1	0	1	0	0	0	0	1
Address	07D0	07D1	07D2	07D3	07D4	07D5	07D6	07D7	07D8	07D9	07DA	07DB	07DC	07DD	07DE	07DF
Use Fixed Data for CPU	2	0	1	0	0	2	1	0	0	0	2	0	0	0	0	2
Address	07E0	07E1	07E2	07E3	07E4	07E5	07E6	07E7	07E8	07E9	07EA	07EB	07EC	07ED	07EE	07EF
This Area Set to Zero	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Address	07F0	07F1	07F2	07F3	07F4	07F5	07F6	07F7	07F8	07F9	07FA	07FB	07FC	07FD	07FE	07FF
This Area Set to Zero	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Address	0800	0801	0802	0803	0804	0805	0806	0807	0808	0809	080A	080B	080C	080D	080E	080F
Use of Address	A(1)	A(2)	A(4)	A(8)	Always 0	Always 0	Always 0	N(1)	N(2)	N(4)	N(8)	N(16)	N(32)	N(64)	N(128)	N(256)
Channel 1 TX Data - example 70.4875MHz TX	1	1	1	0	0	0	0	0	0	0	0	0	1	1	0	1
Address	0810	0811	0812	0813	0814	0815	0816	0817	0818	0819	081A	081B	081C	081D	081E	081F
Use of Address	N(512)	N(1024)	Always 1	Always 0	Always 2	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0
Channel 1 TX Data - example 70.4875MHz TX	0	0	1	0	2	0	0	0	0	0	0	0	0	0	0	0
Address	0820	0821	0822	0823	0824	0825	0826	0827	0828	0829	082A	082B	082C	082D	082E	082F
Use of Address	A(1)	A(2)	A(4)	A(8)	Always 0	Always 0	Always 0	N(1)	N(2)	N(4)	N(8)	N(16)	N(32)	N(64)	N(128)	N(256)
Channel 1 RX Data - example 70.4875MHz (+20.8MHz IF) RX (minus 20.8MHz KME150)	1	1	1	0	0	0	0	0	0	0	1	0	0	1	1	1
Address	0830	0831	0832	0833	0834	0835	0836	0837	0838	0839	083A	083B	083C	083D	083E	083F
Use of Address	N(512)	N(1024)	Always 1	Always 0	Always 2	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0
Channel 1 RX Data - example 70.4875MHz (+20.8MHz IF) RX (minus 20.8MHz KME150)	0	0	1	0	2	0	0	0	0	0	0	0	0	0	0	0
Address	0840
Channel 2 TX Data Max 16 Ch

Once a programmed eprom has been fitted - alignment of set into a dummy load - should be able to get around 30-35W from the KME80

KME 450 (420-470MHz)
The Maths !

In the KME the reference division ratio is defined at the start being either 12.5KHz or 10KHz and cannot be changed per frequency each of the 16 channels must be 12.5KHz or 10KHz steps.

A number of parameters need entered into the Eprom Starting at address 07C0;

The 12.8MHz TCXO is divided by either 1024 to provide a 12.5/25KHz Channel Spacing OR 1280 to provide 20/30KHz Channel Spacing.

12.8MHz/0.0125=1024 or 10000000000 in Binary (put into address 07C0-07CB see table below).

12.8MHz/0.0100=1280 or 10100000000 in Binary (put into address 07C0-07CB see table below).

07CC-07DF Fixed Data for CPU Programming (see table below)

07E0-07FF This area always set to Zero (see table below)

NT Division Ratio (either 1024 or 1280) 1024 = TX Frequency (example 434.600MHz) / 0.0125 = 34768

To obtain N division ratio and A division ratio NT (34768) = 64 x N (543 x 64) + A (Remainder of 16)

N = Number of Complete Divisions of 64

A = Remainder of the Basic Division Rate

N = 543 or 1000011111 in Binary added to channel 1 TX address 0807-0811

A = 16 or 10000 in Binary added to channel 1 TX address 0800-0805

0806 always Zero

0812-081F Always Fixed Data as per table.

NT Division Ratio (either 1024 or 1280) 1024 = RX Frequency (example 433.000MHz-45MHz IF) / 0.0125 = 31040

To Obtain N division ratio and A division ratio NT (31040) = 64 x N (485 x 64) + A (Remainder of 0)

N = Number of Complete Divisions of 64

A = Remainder of the Basic Division Rate

N = 485 or 111100101 in Binary added to channel 1 RX address 0827-0831

A = 0 or 000000 in Binary added to channel 1 RX address 0820-0823

0826 Always Zero

0832-083F Always Fixed Data as per table.

Key KME450 2764 Eprom Coding
Starts at Address 07C0	07C0	07C1	07C2	07C3	07C4	07C5	07C6	07C7	07C8	07C9	07CA	07CB	07CC	07CD	07CE	07CF
Use of Address	N0(1)	N1(2)	N2(4)	N3(8)	N4(16)	N5(32)	N6(64)	N7(128)	N8(256)	N9(512)	N10(1024)	N11(2048)	Fixed for CPU	Fixed for CPU	Fixed for CPU	Fixed for CPU
1024 12.5/25KHz Channel Spacing (N0-N11)	0	0	0	0	0	0	0	0	0	0	1	0	0	0	0	1
1280 20/30KHz Channel Spacing (N0-N11)	0	0	0	0	0	0	0	0	1	0	1	0	0	0	0	1
Address	07D0	07D1	07D2	07D3	07D4	07D5	07D6	07D7	07D8	07D9	07DA	07DB	07DC	07DD	07DE	07DF
Use Fixed Data for CPU	2	0	1	0	0	2	1	0	0	0	2	0	0	0	0	2
Address	07E0	07E1	07E2	07E3	07E4	07E5	07E6	07E7	07E8	07E9	07EA	07EB	07EC	07ED	07EE	07EF
This Area Set to Zero	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Address	07F0	07F1	07F2	07F3	07F4	07F5	07F6	07F7	07F8	07F9	07FA	07FB	07FC	07FD	07FE	07FF
This Area Set to Zero	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Address	0800	0801	0802	0803	0804	0805	0806	0807	0808	0809	080A	080B	080C	080D	080E	080F
Use of Address	A(1)	A(2)	A(4)	A(8)	A(16)	A(32)	Always 0	N(1)	N(2)	N(4)	N(8)	N(16)	N(32)	N(64)	N(128)	N(256)
Channel 1 TX Data - example 434.600MHz TX	0	0	0	0	1	0	0	1	1	1	1	1	0	0	0	0
Address	0810	0811	0812	0813	0814	0815	0816	0817	0818	0819	081A	081B	081C	081D	081E	081F
Use of Address	N(512)	N(1024)	Always 1	Always 0	Always 2	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0
Channel 1 TX Data - example 434.6000MHz TX	1	0	1	0	2	0	0	0	0	0	0	0	0	0	0	0
Address	0820	0821	0822	0823	0824	0825	0826	0827	0828	0829	082A	082B	082C	082D	082E	082F
Use of Address	A(1)	A(2)	A(4)	A(8)	A(16)	A(32)	Always 0	N(1)	N(2)	N(4)	N(8)	N(16)	N(32)	N(64)	N(128)	N(256)
Channel 1 RX Data - example 433.000MHz (-45MHz IF) RX	1	1	1	0	0	0	0	1	0	1	0	0	1	1	1	1
Address	0830	0831	0832	0833	0834	0835	0836	0837	0838	0839	083A	083B	083C	083D	083E	083F
Use of Address	N(512)	N(1024)	Always 1	Always 0	Always 2	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0	Always 0
Channel 1 RX Data - example 433.000MHz (-45MHz IF) RX	0	0	1	0	2	0	0	0	0	0	0	0	0	0	0	0
Address	0840
Channel 2 TX Data Max 16 Ch

Once a programmed eprom has been fitted - alignment of set into a dummy load - should be able to get around 20W from the KME 450 (30W if you change the SO239 Socket for a N-Type Socket !)

Key KME Microphone Wiring

Key KME 32ch Modifications

By programming the Eprom so there are two sets of data (or banks) you can switch between the two giving two sets of 16 channels or 32 in total

Bank 1 starts at 07C0 and ends at 0BFF (as per instructions shown above)

Bank 2 starts at 17C0 and ends at 1BFF (identical format with 2nd set of frequencies)

By applying 5v to Pin 2 of the 2764 Eprom (Address Line A12) it switches to Bank 2 (i.e. from lower 4K to upper 4K)

0v at Pin 2 returns it to the original Bank 1

By including a 4k7 resistor from Pin 2 to Ground, the set switches the banks cleanly over, without stray voltages holding the set in one or other bank.

A simple switch (0v or 5V) on the front panel will alternate between the two banks

A convenient 5v supply can be picked up from the rear of the channel switch on the front panel

When the banks are switched either power down and up again or transmit for the change over to happen, the switch alone will not change the banks (i.e. refresh from the eprom occurs).

This is the easy bit ... some preconfigured files to blow straight into a 2764 Eprom

4 Metres eprom binary code - 4 metres 16 channel Channel Listing

2 Metres eprom binary code - 2 metres 16 channel Channel Listing

2 Metres eprom binary code - 2 metres 32 channel Channel Listing

70 cm eprom binary code - 70cm 16 channel repeaters channels Channel Listing

70 cm eprom binary code - 70cm 16 channel internet linking channels Channel Listing

70 cm eprom binary code - 70cm 32 channel Channel Listing

Below is the chart to select the correct CTCSS tone on the CT5 tone board

CTCSS Tone Chart
Switch	1	2	3	4	5	6
67.0	1	1	1	1	1	1
71.9	0	1	1	1	1	1
74.4	1	1	1	1	1	0
77.0	0	0	1	1	1	1
79.7	1	1	1	1	0	1
82.5	0	1	1	1	1	0
85.4	1	1	1	1	0	0
88.5	0	0	1	1	1	0
91.5	1	1	1	0	1	1
94.8	0	1	1	1	0	1
97.4	1	1	1	0	1	0
100.0	0	0	1	1	0	1
103.5	0	1	1	1	0	0
107.2	0	0	1	1	0	0
110.9	0	1	1	0	1	1
114.8	0	0	1	0	1	1
118.8	0	1	1	0	1	0
123.0	0	0	1	0	1	0
127.3	0	1	1	0	0	1
131.8	0	0	1	0	0	1
136.5	0	1	1	0	0	0
141.3	0	0	1	0	0	0
146.2	0	1	0	1	1	1
151.4	0	0	0	1	1	1
156.7	0	1	0	1	1	0
162.2	0	0	0	1	1	0
167.9	0	1	0	1	0	1
173.8	0	0	0	1	0	1
179.9	0	1	0	1	0	0
186.2	0	0	0	1	0	0
192.8	0	1	0	0	1	1
203.5	0	0	0	0	1	1
210.7	0	1	0	0	1	0
218.1	0	0	0	0	1	0
225.7	0	1	0	0	0	1
233.6	0	0	0	0	0	1
241.8	0	1	0	0	0	0
250.3	0	0	0	0	0	0

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