EMRFD Message Archive 3182

Message Date From Subject
3182 2009-06-11 17:25:44 Bill Pileggi HP8640B technical manual downloads
Dear Ian and group,
There are approx. half-a-dozen HP 8640B technical manuals (commercial and military versions) available for free download from Agilent (ex-HP) and US military (DOD-LOGSA). I'm not using my home computer, otherwise I'd provide URLs. I have all the manuals saved locally - I could also burn a CD and mail to you.

(My 8640B/USM-323 quit a few months ago :-( Likely the hybrid output amplifier(s). Hopefully will get some bench time later this year... I loved that generator!!)

Bill KA3AIS

1d. Re: Hp 8640 Generator
Posted by: "Ian White GM3SEK" gm3sek@ifwtech.co.uk gm3sek
Date: Thu Jun 11, 2009 1:00 am ((PDT))


I have an HP8640A (repeat... "A") which has many of the same features
but doesn't have the digital readout or locking capability.

Does anyone have comments or experience of the 8640A that they'd like to
share?

Also looking for a downloadable manual...
73 from Ian GM3SEK

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3184 2009-06-11 23:59:31 Ian White GM3SEK Re: HP8640B technical manual downloads
Hello Bill

>Dear Ian and group,
>There are approx. half-a-dozen HP 8640B technical manuals
>(commercial and military versions) available for free download from
>Agilent (ex-HP) and US military (DOD-LOGSA). I'm not using my home
>computer, otherwise I'd provide URLs. I have all the manuals saved
>locally - I could also burn a CD and mail to you.
>
>(My 8640B/USM-323 quit a few months ago :-( Likely the hybrid output
>amplifier(s). Hopefully will get some bench time later this year... I loved
>that generator!!)
>

Thank you for the kind offer, but my generator is the model A.

I already downloaded the 8640B manual, but the A model is quite
different because it is free-tuning - there is no frequency locking, no
digital display.

Cutting to the chase, perhaps someone can help with my specific problem?
The output from my 8640A has a very small FM "dither", on the order of a
few tens of Hz at 30MHz. It isn't "noise-like", but sounds more like a
"scintillation" - a T9 signal making tiny discrete jumps in frequency.

It doesn't seem to be associated with tuning or vibration, so I don't
believe it's anything mechanical like a poor sliding contact on the
tuning drive.

My first thought was maybe an intermittent switch contact, somewhere in
the complex FM range switching circuitry... and unfortunately that is
one of the areas where the schematic for the 8640B may not apply to my
8640A.


(Also I must apologise for intermittent replies in the present few days
- we're hosting a visitor from the USA.)


--

73 from Ian GM3SEK