Cheetah SSB/2 (or similar) CB conversion to HAM bands.

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Ian VK3YYY and I are starting to play around with some of the old CBs we have lying around.
We had to scratch our heads a bit to remember the frequency generation numbers for the D858 PLL chips used in the sets in question.
In my "treasures" I fund the Pearce-Simpson Cheetah SSB/2 book that had a block diagram in it.

Does this bring back memories?

So, the first step is to see how hard it is to generate the codes needed to drive the D858 PLL chip. This chip has a BCD input, not straight binary as the PLL020 an similar types do.

Last night, I tossed some Arduino code together. This is a proof of concept and does not yet drive the CB.
The final HEX number produced needs to be written out to the D858, maybe with a shift register or an I2C port expander. As it is is more that 8 bits, a 16 bit chip will be used and the other bits will be available for more functions.
Here is the test display.

Bottom of the band.

Top of the band.

Earlier, testing from the CB part to confirm the numbers.

My aim is to put a rig on 28Mhz, and even 52Mhz.
How many others have old CBs sitting around?

EDIT: I actually have the final number displaying in straight decimal, NOT BCD! Ooops. not quite Fixed!
See the next post.

 

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And here is one to run a couple of 74HC595 shift registers. This has nor been built as yet.

shift reg works

 

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I found an earlier attempt. It is a Shakespeare GBS 2500A. And it looks like I tried to get it going on 6M.
There is a suspicious addon mixer or something.
It is just too long ago as I cannot remember what I was doing with it.

But there is a table covering 51.675 to 54.195 Mhz, making use of the 3 front pannel switches. This is calling out for an Arduino

 

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Here is another one for you Ian
This has the OLED and the LCD.

I have swapped the TRX input and ENCODER_BUTTON pins in the code just for a test. As it is, it sits in TX mode, and pushing the encoder button switches to RX.

 

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This one runs and produces a PWM as a fine tone in 1Khz steps. The PWM table will need to be adjusted to suit the set's clarifier control. And it will need to be enabled on TX.
Here are some blurry pictures of a few steps.
The small numbers on the lower line of the OLED are debugging info, and the right hand number is an example PWM value.