[R-390] 8640B Contrarian opinion.

[Perry Sandeen]

List,

I lust for the dot matrix displays as used on the HP 8640.  If it was new I can see one buying it.

BUT

For a lot less money than a re-furbished and guaranteed 8640 one can buy a HP 8656A/B or HP 8667A series.

They are electronically tuned.  I’m pleased with the one I have EXCEPT it came with the basic time base which is tuned by a single turn pot. Maybe if they had used a 10 turn I wouldn’t gripe.  As is it is almost impossible to set 10 MHz within 1 to 2 Hz.  I’m using an external 10 MHz oscillator until I can add a better one inside. (There is space for a high stability oscillator option.)   

Considering the gear problem, I’d pass.

Regards,

Perrier