[R-390] HP 8640B usage

[Jon Schlegel]

Rasputin,

A -50 dBm level into the multicoupler input is a good median level to 
start with.  Vary the level from there as required.  Even though the 
unit may be dead, increasing the level will usually get enough 
leakage signal through to get a sniff on your receiver.   Also 
presume that the overall gain of the multicoupler around 0 dB.

A typical multicoupler arrangement is an input amplifier followed by 
an n-way splitter and possibly an amplifier following each splitter 
output.  If all outputs are dead, some common element is the problem 
(eg. input amp, splitter).  Depending on where the problem is 
located, you may have to break the signal path at a strategic point 
and "hose in" the generator at the break point to continue your 
search.  After you identify the bad stage, you will have to, "drill 
down from there" as they say.

Regards,
Jon
WA3MVM


At 07:42 AM 1/12/2011 -0800, Rasputin Novgorod wrote:
>Gentlmen:
>
>Thanks to eBuy and other sources, I have some beautiful and
>functional HP test gear, that I used to only dream of having.
>
>Unfortunately, though I have theoretical (book) knowledge of
>it's usage, I've got very little practical experiance.
>
>Right now, I have an active HF antenna amplifier/splitter,
>(multicoupler: one antenna to several radios), that died
>and I'm trying to fix. The power supply is good.
>
>I'd like to connect my HP 8640B to the antenna input, then
>trace the signal. But I have no idea for the power level to
>set the HP 8640B to. Indeed, I'd be very grateful, if someone
>could suggest all the HP 8640B settings for this, to reduce
>my chance of coming to grief...
>
>Sincerely
>/b
>
>
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