questions about OLD cannon speed and temp

[Schools Out]

So a buddy gave me a cannon speed and temp unit he had that was like 20 something years old... it doesnt go on the downrigger cable like the new ones but rather has a probe that gets attached to the transom...

do I need coated cable?

does anyone know about this unit or have any info about it?

any info would be helpful

thanks!

[Schools Out]

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