Hello Bill,

?

Try erevisited@... re your 16NN machine.

?

73 de Brian, VK2GCE.

?

?

I recently dug out two 8640B sig generators I acquired last year. The newer (SN 16xx) has options 1 and 2 and seems to have RF as far as the counter goes but nothing at the output or the meter. The second (SN 14xx) has no options installed; the output (checked with a spectrum analyzer) is clean and the dials match the measurements.? Both units are in okay mechanical condition, the gearing seems to work okay, and each has the usual collection of dents and dings.? I have a couple of questions:

- I can't find a service or operating manual the covers the serial numbers around 14xx. The earlier manuals stop at 13xx and the newer manuals start at 16xx.? Does anyone know of a manual that covers this range? If not a manual, is there a set of change pages that bridges the gap between 13xx and 16xx?

- The working 8640B does what I need for my bench work and seems to be pretty close to specification wrt frequency and output levels, so I am inclined to just put it on my bench and use it. That said, is there some testing or preventive maintenance I should do?

- The non-working 8640B can probably be fixed but working out gear of this complexity is out of my wheelhouse.? Given that the counter suggests that RF is being generated, if I wanted to dig into the RF section, is the best strategy just to start at the N connector and work my way backwards?

Thanks in advance!

Bill