President Jackson CB-Radio

Modification for AM, SSB and to get +5 kHz step

1: Unsolder wire from D74 and R150 to small PCB
2: Unsolder wire on rotary switch
3: Solder wire from R101 to JP32
4: Solder two track on small PCB

Modification for 240 channel

Soldering side:
1: Unsolder the white wire from point C
2: Unsolder the grey, brown, red, yellow, blue and white wires (they were all soldered together)
3: Each of them has to be soldered on its plase (exept the white one which is not necessery anymore and the gray that has another plase)

Components side:

Solder the gray wire onto the programming card, inside the small white circle.

Modification One band above and below standard

To go 1 band lower you would need to change the programming on the binary adders, this is quite easy to do, when you change bands you are actually changing the programming on the binary adders, to go down 1 band you will need to break the signal to the adders from the band switch, this will cause the radio to go down 67 channels below the band "A", to get the radio to be 1 band below band "A" you need to pull pins 4 and 2 high on IC6 and pin 6 high on IC7.

You MUST do this through some diodes other it will cause problems when using other bands.

I would suggest that you take the signal (about 8V) from the switch when in the A band, run it to a switch, which will allow the signal to pass to the binary adders as usual (for normal A band) or through the 3 diodes to the pins I mentioned above.

To go 1 band higher would be quite more tricky, this is because the binary adders can only increase the code by 8 channels from the E band, if this is enough just pull pin 15 of IC6 high (8V) this will make the radio increase by 8 channels on bands A,B and E.

OR a more complex method that will give the band you want would be to do a similar mod as for the 1 band down, use the E band signal through a switch to select either the original or a new set of diodes that will go to pin 2 of IC6 and pins 4, 2 and 15 if IC7, then you will also need to cut the track that goes to pin 11 of the PLL and pull the pin high (about 8V), this will give you an increase of 1 band above the E band, call it F if you like.

Frequency list

Ch.	A	B	C	D	E	F
01	25.615	26.065	26.515	26.965	27.415	27.865
02	25.625	26.075	26.525	26.975	27.425	27.875
03	25.635	26.085	26.535	26.985	27.435	27.885
04	25.655	26.105	26.555	27.005	27.455	27.905
05	25.665	26.115	26.565	27.015	27.465	27.915
06	25.675	26.125	26.575	27.025	27.475	27.925
07	25.685	26.135	26.585	27.035	27.485	27.935
08	25.705	26.155	26.605	27.055	27.505	27.955
09	25.715	26.165	26.615	27.065	27.515	27.965
10	25.725	26.175	26.625	27.075	27.525	27.975
11	25.735	26.185	26.635	27.085	27.535	27.985
12	25.755	26.205	26.655	27.105	27.555	28.005
13	25.765	26.215	26.665	27.115	27.565	28.015
14	25.775	26.225	26.675	27.125	27.575	28.025
15	25.785	26.235	26.685	27.135	27.585	28.035
16	25.805	26.255	26.705	27.155	27.605	28.055
17	25.815	26.265	26.715	27.165	27.615	28.065
18	25.825	26.275	26.725	27.175	27.625	28.075
19	25.835	26.285	26.735	27.185	27.635	28.085
20	25.855	26.305	26.755	27.205	27.655	28.105
21	25.865	26.315	26.765	27.215	27.665	28.115
22	25.875	26.325	26.775	27.225	27.675	28.125
23	25.905	26.355	26.805	27.255	27.705	28.155
24	25.885	26.335	26.785	27.235	27.685	28.135
25	25.895	26.345	26.795	27.245	27.695	28.145
26	25.915	26.365	26.815	27.265	27.715	28.165
27	25.925	26.375	26.825	27.275	27.725	28.175
28	25.935	26.385	26.835	27.285	27.735	28.185
29	25.945	26.395	26.845	27.295	27.745	28.195
30	25.955	26.405	26.855	27.305	27.755	28.205
31	25.965	26.415	26.865	27.315	27.765	28.215
32	25.975	26.425	26.875	27.325	27.775	28.225
33	25.985	26.435	26.885	27.335	27.785	28.235
34	25.995	26.445	26.895	27.345	27.795	28.245
35	26.005	26.455	26.905	27.355	27.805	28.255
36	26.015	26.465	26.915	27.365	27.815	28.265
37	26.025	26.475	26.925	27.375	27.825	28.275
38	26.035	26.485	26.935	27.385	27.835	28.285
39	26.045	26.495	26.945	27.395	27.845	28.295
40	26.055	26.505	26.955	27.405	27.855	28.305

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